Flood Protection Guide 2013
description
Transcript of Flood Protection Guide 2013
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Homeowners Guide to Flood resilience A Living Document
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Contents
Foreword1. Why should I think about flood risk?2. What is the risk to houses from flooding?3. How do I find out if my home is at risk from flooding?4. Should I consider protecting my home from flooding?5. How best to protect myself, my family and my home from flooding?6. Where can I find help?7. The flood protection product information tables8. Permanent resistance 8.1.Preventwaterenteringdoors/windows 8.2.Preventwaterpenetratingwalls 8.3.Preventwaterenteringservicepipes9. Temporary resistance 9.1.Preventwaterenteringdoors/windows 9.2.Preventwaterpenetratingwalls 9.3.Preventwaterenteringservicepipes 9.4.Floodwarningdevices10. Resilience 10.1.Limitwaterdamage 10.2.Removevulnerableitemsfromfloodrisk 10.3.Expelwater11. Case studies12. Directory of flood protection product manufacturers and suppliers13. Useful links and references
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Floodingcanhaveadevastatingimpactonhomesandfamilies.Thiswasclearlyshownbytheterriblefloods,whichhitsomanypartsofEnglandandWalesin2007,Cumbriain2009andagaininsummer2012.
AccordingtoEnvironmentAgencyfigures,over5millionpeopleliveandworkinpropertiesthatareatriskofbeingflooded,withasyetanundefinednumberofpropertiesalsoatriskfromsurfacewaterflooding.
Atthetimeofwriting,asyettherehasbeennoformalagreementregardingareplacementfortheStatementofPrincipleswhichexpiresattheendofJune2013.Asaresult,floodinsurancemaybecomeunavailableorunaffordableforthe200,000homesdeemedatsignificantriskofbeingflooded.Iffloodinsurancecoverischargedaccordingtothelevelofriskahomefaces,manypeopleatriskofbeingfloodedwillseethecostoffloodcoverrisesubstantially.
Asaresultofthepotentialchangestotheavailabilityandaffordabilityoffloodinsurance,protectingyourownhomefrombeingfloodedmaywellseemafavourableoption.However,theprospectisoftenabafflingone,withmanypeoplenotknowinghowtogoaboutprotectingtheirhomesotherthanwiththehumbleandinefficientsandbag.
Thisguidewhichiswrittenespeciallywiththehomeownerinmindhopestoreducetheworryaboutwhatfloodprotectionproductstouse,andillustratesthevarietyofwaysahomecanbeprotected,howdifficulttheproductistofitandwhenitisappropriatetousethem.
Itisoftenthecasewhenthefloodwateristoohighthatitisbettertoletthefloodwaterinandadaptyourhometoreducethedevastationthefloodwatercanhave,sothereisasectiononthistoo,usingcasestudiesfrompeoplewhohavebeenfloodedbuthavenowtakenmovestomaketheirhomesresilienttoflooding.
Sadly,floodingissettogetworseanditisessentialthatwenotonlyknowourownfloodrisk,prepareinadvanceandtakemovestoprotectourownhomes.Beingfloodedisanappallingexperience.ThisguidehasbeenwrittenbytheKnowYourFloodriskcampaigninconjunctionwithRABConsultantsLtdandwehopethatitwillhelpinformyouastowhatcanbedonetomitigateagainstfloodsandhelptoreducethemiserythatbeingfloodedbringswithit.
Foreword
Mary Dhonau, OBE
ChiefExecutiveKnowYourFloodRiskCampaign
Jacki Norbury
ChairmanKnowYourFloodRiskCampaign
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Authors:
Tony Andryszewski(EnvironmentAgency)David Bartram(EnvironmentAgency)Jason Beedell(SmithsGore)Steven Bickers(DEFRA)Chris Brown(JMPConsultantsLtd)Alan Cripps(RoyalInstitutionofCharteredSurveyors)Tim Dawe(JMPConsultantsLtd)Mary Dhonau(ChiefExecutive,KnowYourFloodRisk)Katharine Evans(EnvironmentAgency)Alan Freeman(LincolnshireCountyCouncil)Elved Gray-Jones(EnvironmentAgency)Ron Whitehead(FloodProtectionAssociation)
David Hickman(LincolnshireCountyCouncil)Ben Lukey(EnvironmentAgency)Steve Lumb(BostonBoroughCouncil)Stephen Merrett(EnvironmentAgency)Tony Mulhall(RoyalInstitutionofCharteredSurveyors)David Oake(EnvironmentAgency)Mervyn Pettifor(FloodManagementSupportServicesLtd)Neal Ricketts(EnvironmentAgency)Ian Sinclair(EnvironmentAgency)Jeff Stacey(LondonPortAuthorityandEmergencyPlanningSociety)Andrew Teanby(SmithsGore)
Acknowledgements:
Anyerrors,omissionsand/oranomaliesareentirelyattributabletotheauthors.Thisisalivingdocument.Updatesandamendmentsareencouragedfromusers.Forfeedbackonthehandbook,pleasecontact:
Mr Gavin WilsonRAB Consultants LtdLichfieldBusinessVillage,TheFriary,LichfieldStaffordshireWS136QG
Telephone: 01543308631Email: [email protected]: www.rabconsultants.co.uk
Mary Dhonau(ChiefExecutive,KnowYourFloodRiskCampaign),Gavin Wilson(RABConsultantsLtd),Andrew McHugh(RABConsultantsLtd)andRussell Burton(RABConsultantsLtd).
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Havingsufferedfirsthandfromtheeffectsofbeingflooded,Iknowonlytoowellwhatanappallingexperienceitis.Beingavictimoffloodwaterravagingyourhomehasfar-reachingandlong-termconsequencesforeveryoneconcerned.Floodingisnotjustwhenthemediaandtheministercometovisit.Towatchhelplesslyaseverythingyouhaveworkedsohardforisthrownintoaskipishardenough,buttoloseprecioussentimentalitems-suchaschildren’sfirstdrawingsorphotosofrelativeswhoarenolongerwithus-iscompletelydevastating.
Manypeoplehavetoldmeofoccasionswhentheyhavegonetolookforsomethingonlytorememberithavingbeenlostyearsearlierinaflood;onceagain,thepaincomesteemingbacktohauntthem.Themiseryisfurthercompoundedbyhavingtomoveoutofyourhomeintoalternativeaccommodationformonths,sometimesyearsonendandtostandpowerlesslybyandwatchasyourprecioushomebecomesabuildingsite.Whenre-buildingyourhomedoesn’tgotoplan,itcanoftencausemoreupsetthantheactualflooditself.Itistheseintangibleconsequencesofbeingfloodedthatareoftenoverlookedwhenthinkingaboutprotectingyourhomefrombeingfloodedagaininthefuture.
Manyofushappilyinvestinsmokealarmsandsecuritylockstoprotectourselvesagainstfiresortheftsbutifyouliveinafloodplainyou’refarmorelikelytobefloodedthanhaveyourhouselostinafire.Afloodisthemosteffectiveandindiscriminate‘burglar’thereis,itwilltakeeverythingyouhaveincludingitemsofnovaluetoanyoneelse.Wedon’tstoptothinkaboutinvestinginfloodpreventionaswebelievethatGovernmentshouldprotectus,orourinsurancewillcoverit.Thesadtruthisthatwithsomanyofusatriskofbeingflooded,therejustisn’tenoughGovernmentmoneytoprotecteveryoneandyourinsurancecovermightnotpickupthefullbill.
Whilstprotectingahomefrombeingfloodedisnotcheap,floodinsuranceisbecomingextremelyexpensive;takingstepstoprotectyourhomefromfloodingmayenableyoutoobtaininsuranceatamoreaffordablepricethanwouldotherwisehavebeenavailable,you’llcertainlybelookedonmorefavourablythanifyoudonothing.Ifyoudonotputprotectivemeasuresinplace,youmaybeunabletoobtainfloodinsurancewhichmaywellinvalidateyourmortgage.Couplethatwiththeemotionaleffectsofbeingflooded,floodresistance(protection)andresilience(adaptingyourhomesothatthefloodwaterdoestheleastdamagepossible)suddenlyseemsahighlyfavourableoption.
Forfurtherinformationandguidance,clickonthefollowinglinks:
www.defra.gov.uk/publications/files/pb13684-flood-risk-insurance.pdf
www.defra.gov.uk/publications/files/pb13082-flood-insurance.pdf
Forinformationabouthowtopurchaseafloodreportgotowww.knowyourfloodrisk.co.uk
Flood insurance cover and resistance and resilienceTheUKinsuranceindustrycurrentlyprovidesinsuranceagainstfloodingasastandardfeatureofbuildingsandcontentsinsurance.Inmostcases,householdinsurancepremiumsdonot,currently,reflecttheactualfloodrisktoproperties.Thecostsofflooddamageareoftensharedbetweenthepremiumsofallhouseholders,whetherornottheyareatriskofflooding,althoughasunderstandingoffloodriskimproves,sowilltheabilityofinsurerstopricethisriskmoreaccurately.
Thecurrentcrosssubsidymeansthatmanyhouseholderslivinginhigh-riskpropertiesmaynotbepayingapricewhichreflectstherisk.Itisthereforedifficultforinsurerstoprovidefinancialincentives,
1. Why should I think about flood risk? - For a personal perspective from Mary Dhonau
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throughinsurancepremiumsandexcesses,topromoteresistanceandresilienceasinmanycasesthepremiumwillnotreflectthehighriskoffloodingtotheproperty.Thismaychangeastheinsurancemarketmovestowardsmorerisk-basedpricinginfuture.
Mainstreaminsurerswillgenerallyinsurepropertiesinflood-riskareas,andwillnormallycontinuetoprovidecoverforpropertiesfollowingaflood,albeitthatthismaybeatahigherprice.Mainstreaminsurersmayhoweverrefusetotakeonnewpropertieswithafloodinghistoryorinanareadeemedtobeatsignificantfloodrisk.Therearespecialistbrokersandinsurerswhospecialiseininsuringpropertiesathighfloodrisk,whocanprovidecoverinthemajorityofcases.However,thegeneralpublicmaynotbeawareoftheseoptions,particularlyiftheyrelyonpricecomparisonwebsiteswhichwilltendonlytoshowproductsfrommainstreaminsurers.Thisisaddressedbelow.
How can resistance and resilience help people access affordable insurance currently?
Resistanceandresiliencemeasurescanavoidtheneedtoclaim,orreducethevalueofanyclaimmade,whichcanhelpmaintainaccesstomainstreaminsurance.Itismorecommonforinsurerstotake
accountoffloodresiliencemeasureswhenprovidinginsurancetolargecommercialandpublicsectorcustomers.Forhomes,somespecialistinsurerswilltakeaccountofresistanceandresiliencethatareinstalledtoreducetheeffectsofflooding.Thesespecialistinsurersmayofferawayforpropertiesatveryhighrisk,withahistoryofflooding,tomaintainaccesstoinsurance.
How could this change?
Itispossiblethatinthefuture,insurerswillroutinelyensurethatthefloodrisktoaparticularpropertyisbetterreflectedinthepolicyterms,meaninghigherpremiumsforpropertiesinhigh-flood-riskareas.Ifthemarketdiddevelopinthisway,wewouldexpecttoseeanincreaseinspecialistinsuranceoptionsforpropertiesathighrisk,includinggreaterrecognitionofresistanceandresiliencemeasures.Evennow,thereareanumberofstepsthatcouldbetakentohelpinsurersbetterunderstandtheimpactofresistanceandresiliencemeasuresandtopromoteresistanceandresiliencetohouseholdersatfloodrisk.
The full report is available to view at www.defra.gov.uk.
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i. Surface water flooding.Inprolonged,exceptionallyheavydownpours,whicharebecomingmorefrequent,thegroundmaysaturateandthedrainsandsewerswhichcarryawaysurfacewatermaynotbeabletocopeormayevenbeblockedwithdebrisorhailstones,leadingtosurfacewaterflooding.Surfacewaterfloodingwillflowdownhillandcollectinlow-lyingareaswhichmeansthathousesinlowbasinsoratthefootofslopesmaybeatparticularriskofsurfacewaterflooding.
ii. Groundwater floodinggenerallyoccursduringlongandintenserainfallwheninfiltrationintothegroundraisesthelevelofthewatertableuntilitexceedsgroundlevels.Itismostcommoninlow-lyingareasoverlainbyporoussoilsandrocks,orinareaswithanaturallyhighwatertable.Groundwaterfloodingisaparticularrisktobuildingswithbasements.
iii. River flooding.Riverfloodingoccursfollowingheavyrainfall(ormeltingsnow)acrosstheupstreamreachesandtributariesofawatercoursewherethenormalriverchannelisunabletocarrytheresultinghighflowofwater.Adjacentlow-lyingpropertiesandlandarethenliabletoflood.Riverfloodingcanextendoververylargeareascausingwidespreaddamageandmaybelong-lastinganddifficulttodrainaway.Fast-flowingfloodwaterscanbedangeroustopeopleandanimalsandcanstructurallydamagebuildings.
iv. Coastal and tidal floodingiscausedbyhightidescoincidingwithalow-pressurestormsystemwhichraisesseaandtidalwaterlevels,overwhelmingcoastaldefences.Thismaybemadeworsebystrongwindsblowingseawaterontothecoast.Coastalfloodingmayaffectnotonlypropertyonthecoastitselfbutalsopropertyintidalriverbasinssomedistancefromthecoast,duetofloodwaterbeingforcedupthetidalreachesofrivers.
v. Reservoir or dam failure.TherearemanythousandsofreservoirsandretainedbodiesofraisedwateracrosstheUK,thatposeafloodriskfromfailureoftheretainingdam.Reservoirslargerthan10,000cubicmetresmustberegisteredwiththeEnvironmentAgencyandwillberegularlyinspectedtoensuretheirsafety.DamfailuresintheUKareuncommon,sowhiletheconsequencesofadamfailurearepotentiallycatastrophicandcouldaffectalargearea,thechancesofithappeningareremote.Therearemanysmaller
bodiesofraisedwater,suchasmillpondsandagriculturaltreatmentlagoonsthatmayposeafloodrisklocally.
vi. Burst water mains.Considerableamountsofwatermaybereleased,whichmayfloodthestreetandenteradjacentproperties.Thefloodingisusuallycomparativelyshallowandshort-lived,butmayneverthelesscauseextensivedamagetothegroundfloorsorbasements.
vii. Sewer flooding.Whensewageescapesfromthepipethroughamanhole,drain,orbybackingupthroughtoilets,bathsandsinksthisisknownassewerflooding.Sewerfloodingcanbecausedby:ablockageinasewerpipe;afailureofequipment;toomuchwaterenteringthesewersfromstormrun-off(fromroadsandfields)andriversandwatercourseswhichoverflowed;orthesewerbeingtoosmalltodealwiththeamountofsewageenteringit.Thecauseoftheproblemmaybesomedistanceawayfromwherethefloodingishappening.
Afloodcanhappentoanypropertyfromoneormoreofthesesourcesandatanytime.FormostpropertyintheUKtheriskissmall,howeversomepremisesaremoreatriskthanothersbecauseoftheirgeographiclocationandparticularlocalsituation.Floodingofyourhomewillalmostalwaysinvolvewaterenteringthebuildingfromoutside.Housesareusuallybuilttoprevent‘normal’watersourcesgettinginbytheuseofdampproofmembranes,roofover-hangs,guttering,belowgrounddrainsandraisedfinishedfloorlevelsinthegroundfloor.Normalhouseconstructionisnotdesignedtokeepfloodwateroutwhenlargeamountsofwaterlieagainstthebuildingforanyperiodoftime.Therearemanyroutesbywhichexternalfloodwatercanenteryourhouse.Someareveryobvioussuchasdoorways,windows,airbricksandcracksinwalls.Othersarenotsovisiblesuchaswashingmachineoutlets,downstairstoilets,soakingthroughbrickwalls,belowgroundgapsinthewallsandfloors.Thechanceofwatergettingintoyourhousewillalsodependonthingslikethedepthoffloodwaterandthetimeittakestodrainaway.
2. What is the risk to houses from flooding?There are a number of potential sources of flooding that can threaten your home:
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Thefirstcheckthatyoucando,andwhichdoesn’tcostanything,istoinvestigatewhetheryourpropertyisinariverorcoastalfloodriskareaontheEnvironmentAgency’swebsite.Followlinkstothe‘FloodMap’ontheEnvironmentAgency’swebsiteandenteryourpostcode.Thefloodmaphasadropdownboxatthetopandif‘RiskofFloodingfromRiversandSea’isselectedthenthemapwillindicatetheareasatriskoffloodingwithblueshading,darkblueforthehighestrisk,lighterblue/greenwherethereissomeriskandnoshadingwheretheriskisnegligible.Clickthemapatthelocationofyourhouseandasummaryoffloodriskatthatareawillbeprovided.Theriskisgradedas‘low’,‘moderate’or‘significant’.Theriskoffloodingfromreservoirscanalsobeshown,butthistimewithgreenshading,bychoosingthatoptioninthedropdownmenu.
Thesemapsgiveageneralguideonly,andarenotaccuratedowntoindividualproperties.Theyshowareasatrisk,andifso,whetherthereareconsideredtobeadequateflooddefencesinplace.However,theydonottakeintoaccountlocalvariationsinphysicalfeatures,northeheightofaproperty’slowestfloorabovethesurroundingground.Also,atthetimeofwriting,themapsdonotgiveanyinformationaboutthefloodriskfromsurfacewaterorgroundwater.
Localknowledgeisanimportantsourceofinformationaboutthefloodrisktoyourhome.Long-standingneighboursmayhaveusefulknowledgeaboutfloodingthatoccurredintheareabeforeyoumovedin.Yourlocalcouncilorwatercompanymayholdfloodrecords.
Foramoreaccurateassessmentoffloodriskyoucangotoaspecialistsearchproviderwho,forasmallfee,willprovideyouwithamoredetailed,‘desktop’property-specificreport.Thiswilldeterminetherisksfromthedifferenttypesofflooding,includinglocalgroundwaterandsurfacewaterfloodingriskswhicharenotcurrentlyincludedontheEnvironmentAgency’sfloodmap.Currently(2012)theVATexclusivecostofsuchasearchisaround£20foraresidentialpropertyandaround£100forcommercialpropertiesupto1hectareinsize,thoughbiggerpropertieswillcostmore.Thistypeofreportwillnotgotothelevelofdetailwhereyouwouldknowwhattoexpect
whenafloodoccurs,youmaystillhavequestionssuchas:Fromwhichdirectionwillwatercome?HowmuchwarningwillIget?Howdeepwillthewaterget?Forhowlongwillthewaterstay?HowoftenwillIflood?Willwatergetintomyhouse?CanIprotectmyhome?Aspecialistfloodriskconsultantwouldbeabletoanswerthesequestionsbutyoushouldexpectfeesinexcessof£200.Theseareverymodestcostswhencomparedwiththeoverallpriceofyourhouse,mortgagecostsandongoinginsurancefees.
3. How do I find out if my home is at risk from flooding?
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Whetherandtowhatextentfloodprotectionmeasuresarenecessarywilldependonthedegreeoffloodrisk,andthevulnerabilityofyourhouseandoccupants.AsaminimumyoushouldinvestigatethedegreeofrisktoyourpropertyusingtheEnvironmentAgency’sfloodmap(seequestion3,HowdoIfindoutifmyhomeisatriskfromflooding?).Ifyourpropertylieswithinablueshadedareathefloodmapwillshowthelikelihoodoffloodingas‘lowrisk’,‘moderaterisk’or‘significantrisk’.
Ifyourpropertydoesnotlieinablueshadedarea,itisveryimportanttonotethatthisdoesnotmeanthereisnofloodrisk.TheremaystillberiskoffloodingfromsurfaceorgroundwateroraraisedbodyofwaternotshownontheEnvironmentAgency’sfloodmap.
Ifthereisalowrisk,usuallymeaningthatthechanceoffloodingis1in200inanyyear(InsuranceBand1typepropertiesasabroadguide),buttheriskisnotseriousenoughtosignificantlyaffectthebuildingsinsurance,youshouldmakesomeplansabouthowyouwoulddealwithafloodifonewastooccur,bearinginmindthatfloodsarehappeningtomanypropertieswhichhaveneverpreviouslyflooded.Asaminimum,youneedaFloodPlan(discussedaspartofthenextquestion).Youmayalsoconsiderintroducingsomefloodprotectionmeasureswhenconvenient,forexamplewhenyouarecarryingoutrefurbishmentandreplacementwork.
Iftheriskismoderate,withachanceoffloodingbetween1in75and1in200inanyyear(InsuranceBand2propertiesandsomeothersatlocalrisk),forexampleifthepropertyhaspreviouslybeenflooded,youshouldhaveaFloodPlan(discussedaspartofSection5)andyoumayalsoconsiderwhethersomefloodprotectionmeasurestothepropertywouldbeappropriate.Thesemeasurescanbeimplementedwhenimprovementsandalterationsareundertaken,perhapsasaconsequenceofnewownership,ormaybeundertakensolelytoensurepeaceofmindandmaintainmarketvalue.
Iftheriskissignificant,withachanceoffloodinggreaterthan1in75inanyyear(InsuranceBand3properties,andthosewhichhavebeenfloodedmorethanoncewithinthelasttenyearsorso),youwillneedaFloodPlan
(discussedaspartofSection5)andyoushouldactivelyconsiderfloodprotectionmeasures,inordertomaintaininsurancecoverandtominimisethenegativeimpactonmarketvalue.
Havingdecidedwhetheryoushouldapplyfloodprotection,thenextquestionis,ofthemanyoptionsavailable,whichisthebestchoiceforme?
4. Should I consider protecting my home from flooding?
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Tokeepyourselfandyourfamilysafeandtochoosethebestoptionforprotectingyourhome,youaregoingtoneedsomefactsaboutthefloodriskandfactsaboutthevulnerabilityofyourhouse.Themorereliablethefactsthenthemorecertainyoucanbethatyouhavechosenthebestoption.Factorsthatinfluencethebestchoiceoffloodprotectionisdiscussedbelow.Howeveryoushouldbeawarethatmanyoftheimportantfactscanbedifficulttoestablishandrequiretechnicalknowledgeandexperiencetomakereliableestimates.Youshouldobtainspecialistadvicefromsurveyorswithfloodriskexperienceorspecialisedfloodriskconsultants.
Theareaatriskoffloodingshouldbeidentifiedandthemechanismoffloodingdetermined,suchasthesourceofflooding(e.g.rivers,seas,reservoirs,groundwater,surfacewater,sewersandmainssupply)andthepathwaysthatwaterwilltaketoreachthesite.
Facts about the flood risk
Therearefourfactsaboutthefloodwaterthatareofparticularimportance:
Flood depthsexpectedatyourhouse.Lowdepths,forexample100mm,areunlikelytoputpeopleatriskbutwaterdamagetobuildingsandcontentsmaybesignificantwithoutanyfloodprotection.Highwaterdepths,forexample1m,mayseverelythreatenthesafetyofpeopleandmaycauseextensivedamagetobuildings.Itmaybedangeroustokeepdeepfloodsoutofabuildingbecauseofthelargeweightofwaterpressingagainstthewalls.
Flood durationisthetimethatfloodwaterisexpectedtostayatyourhouse.Temporaryflooddefencesmaysuccessfullykeepwateroutiffloodingisexpectedtolastforjustacoupleofhours,whereas,longflooddurationsmaygivetimeforwatertopenetrateintothebuilding.Itmaybesafetotakerefugeandstayinabuildingforshortdurationfloodsbutthiswilldependontheotherfactors.
Flood onsetisthetimeforfloodwatertoreachyourhousefromitssource.Shortonsetflooding(flashfloods)areparticularlydangerousasthereislittletimeavailabletogetpeopletosafetyortoprotectbuildings.
Flood annual probabilityisameasureofthechanceoffloodingtoyourhouseoverthecourseof1year.Differentapproachestofloodprotectionmaybeneededdependinguponhowlikelyfloodingisexpected.
5. How best to protect myself, my family and my home from flooding?
1000mmpossible300mmtypicalFlood depth
Flood durationhoursdaysweeks
Flood onset
Days Minutes
Hours
Flood annual probability
BAR BARBAR
10% 1% 0.1%
{ Dark blue indicatesstrongapplicabilityofproductsindealingwithflooding,withlight blueindicatingreducingapplicability.}
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Theaforementionedfourkeyfactorsareusedtodecidewhatyouandyourfamilyshoulddowhenfloodingstrikes,forexample‘evacuation’or‘go-in,stay-inandtune-in’.Thefactorsarealsoimportantforguidingthebestwaytofloodprotectyourhome.Aswellaslistingcurrentlyavailablefloodprotectionproducts,thishandbookincludesasimplegraphicalindicationoftheapplicabilityoftheproductstoflooddepth,floodduration,floodonsetandfloodprobability.
Thereareotherimportantfactorsthathaveanimpactonfloodriskatyourhome,notablytheexpectedvelocityoffloodwater.Rapidlyflowingwateratevenlowdepthswillincreasetherisktobothpeopleandbuildings.
Theeffectofflooddefencesshouldalsobetakenintoaccountwhenestimatingtheabovefactors.
SourcesofinformationfortheimportantfactorsincludetheEnvironmentAgency,localauthorityandlocallibraryarchives.Localknowledge,particularlyfromlong-standingresidents,isinvaluable.Calculationsofthingslikerainfall,riverflows,pipecapacitiesandmeasurementsofgroundlevelsmaybeneededtomakereliableestimates,forwhichyoushouldobtainspecialisthelp.
Facts about your home – a property-level surveyApropertylevelsurveyshouldestablishfactssuchasthelevelofthresholdsandfloors,thelikelypointsofwaterentry,whetherattemptsshouldbemadetokeepwateroutofyourhouseorjusttoallowthewaterinandenhancethebuildinginsuchawayastolimitthedamageandpromoterapidcleanup.Theproperty-levelsurveyofyourhouseshouldbeperformedbyanexperiencedprofessional.
TheEnvironmentAgencyhasjustpublishedanewstandardtemplateforsurveyingproperty-levelfloodrisk.ItistheculminationofaprojectledbyDefraandtheEnvironmentAgencyandinpartnershipwithAssociationofBritishInsurers,BritishInstitutionofInsuranceBrokersandtheNationalFloodForum.Thedocumentscanbefoundat:www.environment-agency.gov.uk/research/planning/129526.aspx.ThelinkwilltakeyoutoanEnvironmentAgencywebpagewhichincludesashortexplanationandlinktothereport.Thiswillgivesurveyorsarecognised
frameworkforassessingfloodriskandwillhelppeoplesetoutthefloodriskinformationthatinsurersmayaskthemtoprovide.Thisoffersawayofencouraginginsurerstoacceptgoodpropertylevelprotectionschemesasawayofmitigatinginsurance,andthereforemakinginsurancemoreavailableandaffordable.However,itwillneedtobepromotedtopeople,localauthoritiesandagencies,aswellastheinsuranceindustry.
Choosing the right flood protection productsFloodprotectiondesignedtokeepwateroutofyourhouseisreferredtoasflood resistanceproducts. Temporary flood resistance productsarethosethatneeddeploying(fittingoractivating)priortofloodingarrivingwhereaspermanent flood resistanceproductsdonotneedactivating.Flood resiliencereferstomeasuresthatreduceflooddamagetobuildingsinsituationswherewaterisallowedtoenter.
Theimportantfactsaboutthefloodriskandthefactsaboutyourhome,whentakentogether,willguidethebestchoiceofpermanentresistance,temporaryresistanceorresilienceandtheproductlistsinthishandbookwillhelpwiththis.Otherfactorswillplayapartinthedecisionmakingprocess,suchascost,visualimpact,easeofdeploymentandproductperformance.
Thebestanswerforyourhousewillmostlikelyinvolveacombinationofproducts.Otherrisks,suchasthecontinuedoperationoffireexitdoors,willneedtobeconsideredandcompetingprioritiesbalancedaswellasensuringthatanyprotectionmethodsdonotunnecessarilyaddtofloodingelsewhere.Insomesituations,suchaswheresurfacewateristhemainsourceofflooding,thebestanswermaynotinvolvetheproductsdiscussedinthishandbook,suchasimprovingdrainagesystemsorre-landscapinggardens.
Thechosenfloodprotectionproductswillonlybeeffectiveiftheyareusedintherightway,attherighttimeandarestoredandmaintainedcorrectlytoensuretheirlongtermeffectiveness.Youneedtobeclearaboutthebestwaytoactinafloodemergencytoprotectlivesandbuildings.Afloodplanisessentialforachievingtheseaims.
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Make a Household Flood Plan!Beingpreparedforanemergencywillreducetherisktoyouandyourfamilyandlimitthedamagetoyourhouseanditscontents.
AHouseholdFloodPlanwillneedtoestablishthebestemergencyactionsandwhodoeswhatwhenfloodinglookssettostrike.
Theimportantfactsaboutfloodriskandtheavailabilityoffloodwarningswillguideyourbestactioninanemergency.Evacuationismostappropriatewherefloodingisdeepandfloodwarningswillgiveyoutimetomovetoaplaceofsafetyunaided.Identifyingaplaceofsaferefugewithpossiblerescuebytheemergencyservicesmaybethebestapproachwhererapidfloodingoccursandsafeevacuationisnotpossible.
TheHouseholdFloodPlanshouldclearlylistactionsneededonreceiptofafloodwarning,suchashowtosetupanytemporaryfloodprotectiondevicesaswellasgivingamaintenancescheduletoensurecorrectoperationofdevicesinthefuture.Theplanshouldtakeaccountofthepossibilityoffloodprotectiondevicesfailingortheirdesignbeingexceeded.
FloodwarningsarevitaltotriggertheactionswithintheHouseholdFloodPlan.TheEnvironmentAgencyissuesfloodwarningsforspecificareas.Therearethreefloodwarningcodes:
YoushouldcontacttheEnvironmentAgencyandaskwhetheryourhouseiscoveredbytheFloodlineWarningsDirectserviceandsignupifyoucan.FloodlineWarningsDirectisafreeservicewhichsendsyouadirectmessagewhenfloodingisexpectedandmayaffectyourproperty.Floodwarningswillgiveyoutimetoprepareforfloodingwhichcouldsaveyoutime,moneyandheartache.Youcanreceivewarningsbytelephone,mobile,email,SMStextmessageorfax,whicheveryouprefer.
Thereareotherwarningsystemsthatcanbeusedwhereanareaisn’tcoveredbyaformalfloodwarningservice,forexampletheMetOfficeprovidestheNationalSevereWeatherWarningService(NSWWS)toalertthepublicinadvanceofsevereweatherconditions.TheNSWWSprovidesawarningserviceforfivedifferentweatherelements:Rain,wind,snow,iceandfog.
TheNSWWSissueswarningsandalerts:
• Alertsareissuedwhensevereweatherisexpectedmorethan24hoursahead;
• Warningsareissuedwhensevereweatherisexpectedinthenext24hours.
AllwarningsandalertsappearontheMETOfficewebsitewww.metoffice.gov.uk
Localauthoritiesmayalsoissuewarningstoresidents.Privatefloodlevelalarmsarealsoavailableforpurchase(refertosection9.4).
ItisvitalthatyourHouseholdFloodPlaniskeptuptodate,suchaswhencircumstanceschange,andtomakesurethateveryoneknowswhattodowhatfloodingoccurs.
YourlocalcouncilisanimportantresourcewhencreatingaHouseholdFloodPlanforthingssuchasfindingaplacetoevacuateandwhetheryouarebesttoevacuateorstayinyourhouse.Theymayhaveanemergencyplanningofficertoofferassistance.
TheEnvironmentAgencyprovidesaguideforpreparingaFloodPlanandoffersatemplatetofollowonthewebsite.Youcanaccessthisbyvisitingwww.environment-agency.gov.uk/homeandleisure/floods/38329.aspx.
AFloodAlertmeansthat
floodingispossibleandthatyouneed
tobeprepared.
ASevereFloodWarningmeansthatthereisseverefloodingand
dangertolife.Theseareissuedwhenfloodingisposingsignificantrisktolifeordisruptionto
communities.
AFloodWarningmeansthatfloodingisexpectedandthatyoushouldtakeimmediate
action.Youshouldtakeactionwhenafloodwarningisissuedandnotwaitfora
SevereFloodWarning.
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Thereisalistofusefullinksattheendofthisdocumentwhereyoucangetfurtherhelpandadvice.
InEnglandandWalestheEnvironmentAgencyisresponsibleforbuilding,maintainingandoperatingflooddefencesandforissuingfloodwarningstothepublic,withaparticularemphasisonrivers,seasandreservoirs.TheEnvironmentAgencyhasanextensivewebsitecoveringfloodrisksandwhattodotoprepareforaflood,duringafloodandafteraflood.
Followingthefloodsof2007andthesubsequentPittreport,theFloodandWaterManagementAct2010,LeadLocalFloodAuthorities(LLFA)weresetupwithinlocalauthoritystructurestomanagelocalfloodrisk.YourLLFAwillworkwithemergencyrespondersduringfloodingeventsandduringsevere
eventstheywillprovideadvicetothelocalpublicabouttheincidentandwhatactiontotake.Thismayincludeorganisingrestcentresforevacuatedpeople.
BoththeEnvironmentAgencyandLLFAwillbeabletoassistyouwithunderstandingyourfloodriskanddecidinghowbesttoprotectyourself.Ifyouareatparticularfloodriskandhavepreviouslyflooded,yourlocalcouncilmaybeabletooffersomefinancialassistanceforfloodprotectionmeasuresthroughProperty-LevelFloodProtectionfundingorfromotherlocalauthorityfunds.
6. Where can I find help?
Thefollowingpagesofthishandbookprovidealistoffloodprotectionproductsgroupedintocategoriestohelpyouunderstandthewaytheyworkandtoassistwithchoosingthebestproduct.Eachcategoryisdescribedwithsimplegraphicsshowingthekindoffloodsituationtowhichthatgroupofproductsismostapplicable.Adviceonfloodplansisgivenwithintheproductcategories,suchastheimportanceofwarningsystemstodeployproductsingoodtimeortrainingneededtocorrectlyerectflooddefences.
Alistofproductscurrentlyavailableforeachcategoryisprovidedwithindicativecosts(forapplicationtoasingledwelling),advantages/disadvantagesandsuppliernames.Thetablesarearrangedsoeasycomparisonscanbemadebetweencategoriesofproducttohelpwithselection.
FloodprotectionproductsthathavebeenperformancetestedandhavepassedtheBSistandard,makingthemeligibleforakitemark,areindicatedbytheuseofaBSisuperscript.
Theinformationcontainedinthehandbookwasobtainedfromaliteraturereview,byconsultationwithindustryexpertsandawiderangeofmanufacturersandsuppliersofproducts.Awebsearchwasundertaken(January2011)toprovideaswidearangeofproducts,manufacturersandsuppliersaspossible.InNovember2012,RABConsultantsemailedallsuppliers/manufacturerslistedintheappendixoftheguideandrequesteddetailsofanynewordiscontinuedproducts.ThisguidecontainstheinformationreceivedfromthisconsultationandprovidesthecorrectanduptodatecontactinformationforthecompanieslistedinSection12.Noendorsementisgivenofanyproductsorserviceslisted.Theinformationisdesignedtoactasadirectoryforyourassistance.Thisisalivingdocument.Updatesandamendmentsareencouragedfromusers,manufacturersandsuppliers.Pleaserefertotheforewordfordetails.
7. The flood protection product information tables
13
Resistancemeasuresareaimedatkeepingfloodwateroutofabuilding.Theyaredesignedtolessenthedamagethatfloodwatercanhaveandalsogivehomeownersextratimetomovegroundfloorcontents.Themeasuresmayonlybeeffectiveforalimitedtimeandlimitedwaterdepth.Permanentresistancemeansthatfloodprotectionispermanentlyinplacewithnoactionneededtodeploythedevice-permanentresistanceisa‘fitandforget’approach.
8. Permanent resistance
8.1 Prevent water entering doors/windows
8.2 Prevent water penetrating walls
8.3 Prevent water entering service pipes
14
8.1 Permanent Resistance – Prevent water entering doors/windows
Description Thesearepermanentresistanceproductsdesignedtostopwaterenteringyourhousethroughdoorsandwindows.Theseproductswillonlykeepwateroutiftheyarecorrectlyusedaspartofapackageofmeasuresidentifiedfromaproperty-levelfloodprotectionsurveycarriedoutbyaqualifiedandexperiencedsurveyor.Noparticularactionisrequiredbyyoutomaketheproductworkandsotheywillprotectevenwhileyouareawayfromyourhouseandiffloodingarrivesquicklywithnowarning.Theproductsaredesignedtokeepwateroutforlongperiods,howeverseepageispossibledependinguponworkmanshipandfloodconditions,infacttheexistingBSikitemarkstandardallowsforsomeseepage.Thereisarisktothestructureofyourhouseifdeepwaterisheldbackbytheexternalwallsduetothepressureofwater.Forthisreasontheproductsareonlysuitableforlimitedflooddepths.Astructuralassessmentofthebuildingisrecommendedwhereflooddepthsinexcessof300mmareintendedtoberesisted.
Flood plan considerationsTheseproductsdonotrequireactivatingtomakethemworkandsoprotectiontoyourhousedoesnotdependuponreceivingandactingonafloodwarning.Notrainingisneededtooperatetheproductsandnolongtermstorageofitemsisrequired.Routineinspectionandmaintenanceoftheproductsishoweveressential.
Creatingafloodplanisimportantforprotectingpeopleandyourpropertyinanemergency.Aswellasstatingwhodoeswhatwhenfloodingisexpected,thefloodplanshouldsaywhattodoina‘worstcasescenario’suchaswaterseepagethroughfloodprotectiondevices,floodingthatexceedsthedesignofthefloodprotectionproductsandpeoplebeingtrappedinthehousewithrisingwater.
1000mmpossible300mmtypicalFlood depth
Flood duration
hoursdaysweeks
Flood onset
Days Minutes
Hours
Flood annual probability
BAR BARBAR
10% 1% 0.1%
Required input of people Low Mid High
Dark blue indicatesstrongapplicabilityofproductsindealingwithflooding,withlight blueindicatingreducingapplicability.
Product type Indicative cost for a single house
Advantages Disadvantages Available products/suppliers Images
Raised porch/threshold £1.5k(threshold)£5-£10k(porch)
Unobtrusive.Multifunctional.
Lowflooddepth.Disabledaccess.Mayneedwater-proofdoor.Noqualitystandardforfloodprotection.
Auto-barriers Unobtrusive.
£5kto£15k Unobtrusive.Highflooddepth.BSiPAS1188-1.
Highinitialcost.Belowgroundwork.Mayneedmeasurestodealwithseepage.
FloodBreak.FloodControlInternationalLtd.SCFB™(selfclosingfloodbarrier).
Water-resisting external doors/windows
£0.75kto£5k Unobtrusive.BSiPAS1188-1.
Mayneedmeasurestodealwithseepage.Difficulttoevacuateifpeoplearetrappedinsidewithrisingwater.Adoormaykeepwateroutatdepthsthataredangeroustothestructureofthebuilding.
AquobexFloodDoorBSi.FlashFloodDoorsLtdBSi.FloodAngel®–floodproofdoorBSi.Revetment–floodcontroldoorsBSi.WhitehouseBSi.
Otherproductsandsuppliersinclude:DefenceDoorsLtd.FloodguardUK(FloodProofdoors).
Sealant around external doors/windows
Verylowcost Unobtrusive.Inexpensive.
Needscarefulapplication.Reliesonwaterproofdoors/windows.Noqualitystandard.Mayneedmeasurestodealwithseepage.
FloodAngel®Silicone.Siliconesealantsarewidelyavailable.
Ref:SevernTrent
FloodAngel®Silicone
FlashFloodDoors
16
8.2 Permanent Resistance – Prevent water penetrating walls
Description Thesearepermanentresistanceproductsdesignedtostopwaterenteringyourhousethroughwalls.Theseproductswillonlykeepwateroutiftheyarecorrectlyusedaspartofapackageofmeasuresidentifiedfromaproperty-levelfloodprotectionsurveycarriedoutbyaqualifiedandexperiencedsurveyor.Noparticularactionisrequiredbyyoutomaketheproductworkandsotheywillprotectevenwhileyouareawayfromyourhouseandiffloodingarrivesquicklywithnowarning.Theproductsaredesignedtokeepwateroutforlongperiods,howeverseepageispossibledependinguponworkmanshipandfloodconditions,infacttheexistingBSikitemarkstandardallowsforsomeseepage.Thereisarisktothestructureofyourhouseifdeepwaterisheldbackbytheexternalwallsduetothepressureofwater.Forthisreasontheproductsareonlysuitableforlimitedflooddepths.Astructuralassessmentofthebuildingisrecommendedwhereflooddepthsinexcessof300mmareintendedtoberesisted.
Flood plan considerationsTheseproductsdonotrequireactivatingtomakethemworkandsoprotectiontoyourhousedoesnotdependuponreceivingandactingonafloodwarning.Notrainingisneededtooperatetheproductsandnolongtermstorageofitemsisrequired.Routineinspectionandmaintenanceoftheproductsishoweveressential.
Creatingafloodplanisimportantforprotectingpeopleandyourpropertyinanemergency.Aswellasstatingwhodoeswhatwhenfloodingisexpected,thefloodplanshouldsaywhattodoina‘worstcasescenario’suchaswaterseepagethroughfloodprotectiondevices,floodingthatexceedsthedesignofthefloodprotectionproducts,peoplebeingtrappedinthehousewithrisingwater.
1000mmpossible300mmtypicalFlood depth
Flood duration
hoursdaysweeks
Flood onset
Flood annual probability
BAR BARBAR
10% 1% 0.1%
Required input of people Low Mid High
Dark blue indicatesstrongapplicabilityofproductsindealingwithflooding,withlight blueindicatingreducingapplicability.
Days Minutes
Hours
17
Product type Indicative cost for a single house
Advantages Disadvantages Available products/suppliers Images
Re-pointingRepair cracks in wallsSeal service outlets
Lowcost Unobtrusive.Inexpensive.
Needscarefulapplication.Needswater-resistantformula.Mayjustreducepenetrationrate.Noqualitystandard.
Correctlyappliedsiliconesealant.UKFloodBarriers.StormdryRe-pointing.Additive2(SafeguardEurope).WatertightInternational.
Covering weep holes Lowcost Unobtrusive.BSiPAS1188-1mayberelevant.BSiPAS1188-3mayberelevantifabuildingskirtsystemisused.
Needsgoodworkmanship.Nokitemarkedproductscurrentlyavailable.Maycausedampproblemsifpermanentlycovered.
FloodAngel®Anti-floodWeephole.
Facing bricks £1000 Moreeffectivethansealingexistingwall.
Needsgoodworkmanship.Belowgroundwork.Mayneedplanningapproval.Mayjustreducepenetrationrate.Visuallyaltersbuilding.Noqualitystandard.
Engineeringbricks.
Render £2000 Should seal all
£2000 Shouldsealallcracksevenwhenwallsareinrelativelypoorcondition.
Needsgoodworkmanship.Belowgroundwork.Mayneedplanningapproval.Mayjustreducepenetrationrate.Mayneedfacingbricksaswell.Visuallyaltersbuilding.Noqualitystandard.Mayleadtodampwithinthewalls.
Kiltox.Vandex–SafeguardEurope.
Anuncoveredweephole)
Ref:SevernTrent
Ref:SevernTrent
18
Product type Indicative cost for a single house
Advantages Disadvantages Available products/suppliers Images
Wall sealant £500(materials) Unobtrusive.Inexpensive.Easilyapplied.
Needscarefulapplication.Mayjustreducepenetrationrate.Noqualitystandard.Mayleadtodampwithinthewalls.Brickworkneedstobeingoodconditiontobeeffective.
Aquobex.DrybaseliquidappliedDPM(SafeguardEurope).FloodAngel®Waterstop.Floodguards.ICOPAL.NanoshellStormdryMasonryProtectionCream.Stormdry(SafeguardEurope).Revetment.WatertightInternational.
Permanent wallbarrier
£3k-£30k Canuseglasstominimisevisualimpactandallowlightthrough.Woodeffecttomimicafence.BSiPAS1188-3.
Expensive.Needscarefuldesignandconstruction.Lossoffloodplain.Mayneedmeasurestodealwithseepage.
Bespokeoptionsareavailablefromvariousspecialistcontractors.
Tanking £10k-£20k Designedtocompletelywaterproof.Offersgroundwaterprotection.Significantguaranteesandexperience.
Expensive.Needssumpandpump.Vulnerabletodamageduetolateralterations.Primarilydesignedtoprotectagainstgroundwater.
Aquobex.FloodAngel®TankingPolymer.ICOPAL.Kiltoxtankingrender.Revetment.TritonChemicalManufacturingCoLtd.Vandex–SafeguardEurope.
Ref:Stormdry–SafeguardEurope
Ref:NationalFloodForumnewsletterMay2009
Ref:Revetment
19
Product type Indicative cost for a single house
Advantages Disadvantages Available products/suppliers Images
Water-resisting airbricks £0.5k-£1k Inexpensive.Unobtrusive.BSiPAS1188-1
Needscarefulinstallationandmaintenance.Mayneedmeasurestodealwithseepage.
FloodAngel®Anti-floodAirbrickBSi.
Otherproductsandsuppliersinclude:
FloodControlInternational.SMARTAirBrick.Snorkelvent.UKFloodBarriers.
Seal gap between DPC and DPM
Expected£1k-£5k Unobtrusive. Needscarefulinstallation.Noqualitystandard.
SafeguardEurope.TritonChemicals.
Ref:Snorkelvent
20
8.3 Permanent Resistance – Prevent water entering service pipes
Description Thesearepermanentresistanceproductsdesignedtostopwaterenteringyourhousethroughservicepipes.Theseproductswillonlykeepwateroutiftheyarecorrectlyusedaspartofapackageofmeasuresidentifiedfromaproperty-levelfloodprotectionsurveycarriedoutbyaqualifiedandexperiencedsurveyor.Noparticularactionisrequiredbyyoutomaketheproductworkandsotheywillprotectevenwhileyouareawayfromyourhouseandiffloodingarrivesquicklywithnowarning.Theproductsaredesignedtokeepwateroutforlongperiods,howeverseepageispossibledependinguponworkmanshipandfloodconditions,infacttheexistingBSikitemarkstandardallowsforsomeseepage.Thereisarisktothestructureofyourhouseifdeepwaterisheldbackbytheexternalwallsduetothepressureofwater.Forthisreasontheproductsareonlysuitableforlimitedflooddepths.Astructuralassessmentofthebuildingisrecommendedwhereflooddepthsinexcessof300mmareintendedtoberesisted.
Flood plan considerationsTheseproductsdonotrequireactivatingtomakethemworkandsoprotectiontoyourhousedoesnotdependuponreceivingandactingonafloodwarning.Notrainingisneededtooperatetheproductsandnolongtermstorageofitemsisrequired.Routineinspectionandmaintenanceoftheproductsishoweveressential.
Creatingafloodplanisimportantforprotectingpeopleandyourpropertyinanemergency.Aswellasstatingwhodoeswhatwhenfloodingisexpected,thefloodplanshouldsaywhattodoina‘worstcasescenario’suchaswaterseepagethroughfloodprotectiondevices,floodingthatexceedsthedesignofthefloodprotectionproducts,peoplebeingtrappedinthehousewithrisingwater.
1000mmpossible300mmtypicalFlood depth
Flood duration
hoursdaysweeks
Flood onset
Days Minutes
Hours
Flood annual probability
10% 1% 0.1%
Required input of people Low Mid High
Dark blue indicatesstrongapplicabilityofproductsindealingwithflooding,withlight blueindicatingreducingapplicability.
BAR BARBAR
21
Product type Indicative cost for a single house
Advantages Disadvantages Available products/suppliers Images
Non-return valves for wastewater pipes and washing machine outlets.
£50to£500 Unobtrusive.Inexpensive.Easyfit.BSEN13564.
Mayneedtoassesstheimpactonneighbours.Noqualitystandard.
WatertightInternationalBSi.
Otherproductsandsuppliersinclude:
Aquobex-Flusher.CombinedHarvesters.FloodAngel®160mm/110mmNon-ReturnValve.FloodAngel®50mmBackwaterValve.FloodGuardsSystemsLtd.FloodSenseLtd.Marley.MissionRubber.Revetment-Flusher.UKFloodBarriers–fullportbackflowvalve.Whitehouse.
Seal around service entry points.
Unobtrusive.Inexpensive.
FloodAngel®ServiceEntryPanel.SiliconeSealant.
WatertightInternationalnon-returnvalve
22
Resistancemeasuresareaimedatkeepingfloodwateroutofabuilding.Theyaredesignedtolessenthedamagethatfloodwatercanhaveandalsogivehomeownersextratimetomovegroundfloorcontents.Themeasuresmayonlybeeffectiveforalimitedtimeandlimitedwaterdepth.Temporaryresistancemeansthatproductswillneedtobeinstalledbeforefloodwaterarrivesinordertobeprotected.
9. Temporary resistance
9.1 Prevent water entering doors/windows
9.2 Prevent water penetrating walls
9.3 Prevent water entering service pipes
9.4 Flood warning devices
23
9.1 Temporary Resistance – Prevent water entering doors/windows
Description Thesearetemporaryresistanceproductsdesignedtostopwaterenteringyourhousethroughdoorsandwindows.Theseproductswillonlykeepwateroutiftheyarecorrectlyusedaspartofapackageofmeasuresidentifiedfromaproperty-levelfloodprotectionsurveybyaqualifiedandexperiencedsurveyor.Theproductswillneedtobeinstalledingoodtimebeforefloodwaterarrivesandthenremovedoncethefloodriskhaspassed.Theproductsaredesignedtokeepwateroutforlongperiods,howeverseepageispossibledependinguponworkmanshipandfloodconditions,infacttheexistingBSikitemarkstandardallowsforsomeseepage.Thereisarisktothestructureofyourhouseifdeepwaterisheldbackbytheexternalwallsduetothepressureofwater.Forthisreasontheproductsareonlysuitableforlimitedflooddepths.Astructuralassessmentofthebuildingisrecommendedwhereflooddepthsinexcessof300mmareintendedtoberesisted.
Flood plan considerationsTheseproductsrequireactivatingtomakethemworkandsoprotectiontoyourhousedependsuponreceivingandactingonafloodwarning.Sometrainingwillbeneededtocorrectlyoperatetheproductsandlongtermstorageofitemsmayberequired.Routineinspectionandmaintenanceoftheproductsishoweveressential.
Creatingafloodplanisimportantforprotectingpeopleandyourpropertyinanemergency.Aswellasstatingwhodoeswhatwhenfloodingisexpected,thefloodplanshouldsaywhattodoina‘worstcasescenario’suchaswaterseepagethroughfloodprotectiondevices,floodingthatexceedsthedesignofthefloodprotectionproducts,peoplebeingtrappedinthehousewithrisingwater.
2-4mforsomebarriers300mmtypicalFlood depth
Flood duration
hoursdaysweeks
Flood onset
Flood annual probability
Required input of people
10% 1% 0.1%
Low Mid High
Dark blue indicatesstrongapplicabilityofproductsindealingwithflooding,withlight blueindicatingreducingapplicability.
BAR BARBAR
Days Minutes
Hours
24
Product type Indicative cost for a single house
Advantages Disadvantages Available products/suppliers Images
Entrance door/patio door/garage door/window barriers
£0.5kto£3k Rapiddeployment.Relativelylowcost.Lowweightandeasydeployproductsavailable.Kitemarkedproductsavailable(BSiPAS1188-1).Alargechoiceofproducts.
Storageofitems.Somebarriersneedtoolsfordeployment.Permanentfixingsonthebuildingwithmostproducts.Deploymentmaybedifficultforpeoplewithspecialphysicalneeds.NoKitemarkforDIYfittedproducts.Mayneedmeasurestodealwithseepage.
AquobexBSi.FloodgateBSi.FloodguardsBSi.FloodtiteBSi.FloodAngel®FloodDefenderTMSingle&DoubleBSi.FloodAngel®SentinelBarrier.FloodArkBSi.FloodWallBSi.Revetment–floodguardsBSi.WatertightInternational–FloodBarriersBSi.
Otherproductsandsuppliersinclude:
Caro–WaterDoor.CombinedHarvesters.FloodAngel®.Floodaway–Multi-FloodSolutions.FloodControlInternational.FloodPlan.FluvialInnovations–FloodStop.FloodShield.Newlands-FloodBuddy.TotalFloodSolutions.
Sandbags/adsorbent bags Relativelylowcost Absorbentbags:Lightweight.Readytouse.Quicktodeploy.Holdstensoflitresofwater.
Sufficientbagsmustbestoredreadyforuse.Usedbagsneedtobedisposed.Kitemarkdoesnotseemtobeapplicable.
Absorbeez.Aqua-sac®.FloodSax.Sorbarix.
FloodguardscourtesyofRevetment
Ref:FloodArk
Floodsax
25
Product type Indicative cost for a single house
Advantages Disadvantages Available products/suppliers Images
Pet flap covers
Relativelylowcost Rapiddeployment.Relativelylowcost.Lowweightandeasydeployment.
Storageofitems.Somebarriersneedtoolsfordeployment.Permanentfixingsonthebuildingwithmostproducts.Deploymentmaybedifficultforpeoplewithspecialphysicalneeds.NoKitemark.
FloodAngel®FloodDefenderTMSingle&DoubleBSi.Aquobex.Revetment.
De-mountable barriers £10kto£40k Propertyfullyprotected.Structureofbuildingisnotthelimitingfactor.ApplicablekitemarkBSiPAS1188-4.Someproductscanbestoredinsitu.
Needsufficientwarning.Someknowledgeandacertaindegreeofphysicalabilityisrequired.Mostproductsneedseparatestorage.Significantlossoffloodplain.Highinitialcosts.Groundworksrequired.Mayneedpumpstodealwithseepage.Securitymaybeneededtopreventbarriertheft.
Caro–WaterWallBSi.FloodAngel®FloodDefenderTMSingle&DoubleBSi.FloodAngel®SentinelBarrier.
Otherproductsandsuppliersinclude:
AET-AlteauFloodBarrier.Aquobex.DutchDam.Multi-FloodSolutionsMultipleSpanDemountableBarriers(FloodControlInternational).RevetmentIn-situbarrier.McArthurGroupTiltDamandSpringDam.
UKFloodBarriers
Caro-Waterfall
26
Product type Indicative cost for a single house
Advantages Disadvantages Available products/suppliers Images
Free-standing barriers £10kto£40k Propertyfullyprotected.Structureofbuildingisnotthelimitingfactor.ApplicablekitemarkBSiPAS1188-2.
Needsufficientwarning.Someknowledgeandacertaindegreeofphysicalabilityisrequired.Mostproductsneedseparatestorage.Significantlossoffloodplain.Highinitialcosts.Mayneedsignificantmanpowertodeploy.Designedmoreforcommunitiesratherthanindividuals(smallGeodesignbarriercanbeinstalledby1individual).Thesebarrierscanbeinstalledinwater.Mayneedmeasurestodealwithseepage.
GeodesignBSi.RapidamBSi.
Otherproductsandsuppliersinclude:Aquadam.AquaFence.AquaTube.Aquobex-EcoDamFluvialInnovations–Tubewall.FloodStop.WaterGate.
FloodSkirts £10kto£35k Propertyfullyprotected.Structureofbuildingisnotthelimitingfactor.ApplicablekitemarkBSiPAS1188-3.
Needsufficientwarning.Someknowledgeandacertaindegreeofphysicalabilityisrequired.Mostproductsneedseparatestorage.Highinitialcosts.Mayneedmeasurestodealwithseepage.
TotalFloodSolutions.
Perimeter flood wall with gates
£5kto£15k Propertyfullyprotected.Structureofbuildingisnotthelimitingfactor.KitemarkBSiPAS1188-4maybeapplicable.
Needsufficientwarning.Significantlossoffloodplain.Needscontinuityofbarrier.Highinitialcosts.Mayneedmeasurestodealwithseepage.
Aquobex.Floodguards.FloodControlInternational.Revetment.
FloodControlInternational
Ref:DEFRAR&Dtechnicalreport,PamBowker,2007
Ref:Aquafence
27
9.2 Temporary Resistance – Prevent water penetrating walls
Description Thesearetemporaryresistanceproductsdesignedtostopwaterenteringyourhousethroughwalls.Theseproductswillonlykeepwateroutiftheyarecorrectlyusedaspartofapackageofmeasuresidentifiedfromaproperty-levelfloodprotectionsurveycarriedoutbyaqualifiedandexperiencedsurveyor.Theproductswillneedtobeinstalledingoodtimebeforefloodwaterarrivesandthenremovedoncethefloodriskhaspassed.Theproductsaredesignedtokeepwateroutforlongperiods,howeverseepageispossibledependinguponworkmanshipandfloodconditions,infacttheexistingBSikitemarkstandardallowsforsomeseepage.Thereisarisktothestructureofyourhouseifdeepwaterisheldbackbytheexternalwallsduetothepressureofwater.Forthisreasontheproductsareonlysuitableforlimitedflooddepths.Astructuralassessmentofthebuildingisrecommendedwhereflooddepthsinexcessof300mmareintendedtoberesisted.
Flood plan considerationsTheseproductsrequireactivatingtomakethemworkandsoprotectiontoyourhousedependsuponreceivingandactingonafloodwarning.Sometrainingwillbeneededtocorrectlyoperatetheproductsandlongtermstorageofitemsmayberequired.Routineinspectionandmaintenanceoftheproductsishoweveressential.
Creatingafloodplanisimportantforprotectingpeopleandyourpropertyinanemergency.Aswellasstatingwhodoeswhatwhenfloodingisexpected,thefloodplanshouldsaywhattodoina‘worstcasescenario’suchaswaterseepagethroughfloodprotectiondevices,floodingthatexceedsthedesignofthefloodprotectionproducts,peoplebeingtrappedinthehousewithrisingwater.
1000mmpossible300mmtypicalFlood depth
Flood duration
Flood onset
Flood annual probability
BAR BARBAR
10% 1% 0.1%
Required input of people Low Mid High
Dark blue indicatesstrongapplicabilityofproductsindealingwithflooding,withlight blueindicatingreducingapplicability.
hoursdaysweeks
Days Minutes
Hours
28
Product type Indicative cost for a single house
Advantages Disadvantages Available products/suppliers Images
Airbrick covers £50to£300 Inexpensive.ApplicablekitemarkBSiPAS1188-1.
Needsufficientwarning.Requiresstorageandtobeeasilylocatedafterafloodwarning.Mayneedmeasurestodealwithseepage.
FloodArkBSi.FloodAngel®Anti-floodAirbrickCoverBSi.FloodguardsBSi.RevetmentBSi.
Otherproductsandsuppliersinclude:AquobexEasifitVentguard.FloodControlInternational.Floodgate.FloodPlan.FloodSentry.VentBuddy.WatertightInternational.
FloodArk
29
9.3 Temporary Resistance – Prevent water entering service pipes
Description Thesearetemporaryresistanceproductsdesignedtostopwaterenteringyourhousethroughservicepipes.Theseproductswillonlykeepwateroutiftheyarecorrectlyusedaspartofapackageofmeasuresidentifiedfromaproperty-levelfloodprotectionsurveycarriedoutbyaqualifiedandexperiencedsurveyor.Theproductswillneedtobeinstalledingoodtimebeforefloodwaterarrivesandthenremovedoncethefloodriskhaspassed.Theproductsaredesignedtokeepwateroutforlongperiods,howeverseepageispossibledependinguponworkmanshipandfloodconditions,infacttheexistingBSikitemarkstandardallowsforsomeseepage.Thereisarisktothestructureofyourhouseifdeepwaterisheldbackbytheexternalwallsduetothepressureofwater.Forthisreasontheproductsareonlysuitableforlimitedflooddepths.Astructuralassessmentofthebuildingisrecommendedwhereflooddepthsinexcessof300mmareintendedtoberesisted.
Flood plan considerationsTheseproductsrequireactivatingtomakethemworkandsoprotectiontoyourhousedependsuponreceivingandactingonafloodwarning.Sometrainingwillbeneededtocorrectlyoperatetheproductsandlongtermstorageofitemsmayberequired.Routineinspectionandmaintenanceoftheproductsishoweveressential.
Creatingafloodplanisimportantforprotectingpeopleandyourpropertyinanemergency.Aswellasstatingwhodoeswhatwhenfloodingisexpected,thefloodplanshouldsaywhattodoina‘worstcasescenario’suchaswaterseepagethroughfloodprotectiondevices,floodingthatexceedsthedesignofthefloodprotectionproducts,peoplebeingtrappedinthehousewithrisingwater.
Flood annual probability
BAR BARBAR
10% 1% 0.1%
Required input of people Low Mid High
Dark blue indicatesstrongapplicabilityofproductsindealingwithflooding,withlight blueindicatingreducingapplicability.
1000mmpossible300mmtypicalFlood depth
Flood duration
Flood onset
hoursdaysweeks
Days Minutes
Hours
30
Product type Indicative cost for a single house
Advantages Disadvantages Available products/suppliers Images
Toilet plugs £50 Inexpensive.Nopermanentinstallationrequired.
Needsufficientwarning.Requiresstorageandtobeeasilylocatedafterafloodwarning.Needstobecorrectlydeployed.Nokitemark.
FloodAngel®ToiletBung.Floodtitepanseal.UKFloodBarriers.FloodControlInternationalLtd.
Bolt-down inspection covers
Inexpensive. Inexpensive. Needsufficientwarning.Needstobecorrectlydeployed.Nokitemark.
TotalFloodSolutions.
Appliance vent covers Inexpensive. Inexpensive. Needsufficientwarning.Needstobecorrectlydeployed.Nokitemark.
FloodAngel®FloodDefenderTMSingle&DoubleBSi.
Floodguards.MultiFloodSolutions.
Mostmanufacturersofbespokedoorbarriers.
Pipe bungs Inexpensive. Inexpensive. Needsufficientwarning.Needstobecorrectlydeployed.Nokitemark.
Flowstop.
Floodguards
Ref:Flowstop
FloodAngel®inflatableU-bendtoiletbung
31
Floodwarningsarevitalinordertoknowwhentocarryoutthefloodplanandinstalltemporaryresistanceproducts.
TheEnvironmentAgencyprovidesafreefloodwarningserviceforcommunitiesatriskofflooding.TofindoutifaserviceisavailableforyouandtosubscribecontactFloodlineon08459881188.Thisservicesendsyouadirectmessagewhenfloodingisexpectedandmayaffectyourproperty.Floodwarningswillgiveyoutimetoprepareforfloodingwhichcouldsaveyoutime,moneyandheartache.Youcanreceivewarningsbytelephone,mobile,email,SMStextmessageorfax,whicheveryouprefer.YoucanalsoviewfloodwarningsthroughtheEnvironmentAgencywebsiteandthroughtheirtwitteraccountsandFacebookpagesbyvisiting:
Website:www.environment-agency.gov.uk
Twitter:follow@EnvAgencyORifyouinWalesfollow@EnvAgencyWales
Facebook:www.facebook.com/environmentagencyORifyouliveinWaleswww.facebook.com/envagencywales
Thereareotherwarningservicesthatareavailablewhereanareaisn’tcoveredbyaformalfloodwarningservice,forexampletheMetOfficeprovidesaNationalSevereWeatherWarningService(NSWWS)towarnthepublicofsevereweather.TheNSWWSwarnsforfivedifferentweatherelements:Rain,Wind,Snow,FogandIce.
TheNSWWSissueswarningsandalerts:
• Alertsareissuedwhensevereweatherisexpectedmorethan24hoursahead;
• Warningsareissuedwhensevereweatherisexpectedinthenext24hours.
Theonlydifferencebetweenwarningsandalertsistheleadtimeinwhichtheyareissued.AllwarningsandalertsappearontheMetOfficewebsitewww.metoffice.gov.ukandarealsocommunicatedtothepublicviaelectronicandbroadcastmedia.
Localauthoritiesmayalsoissuewarningstoresidents.Privatefloodlevelalarmsarealsoavailableforpurchase.Thesewillnormallyincludeawatersensorandanalarmunit.Thesensorwilldetectfloodwaterandsendasignaltothealarmunitthatwillmakeasoundanalerttowarnyouoftheapproachingfloodrisk.Thesensorwillneedtobecarefullyinstalledatalocationwhererisingfloodwaterwillbedetectedwellbeforeyourhouseisabouttofloodtoalertyouoftherisk(suchasduringthenight)andtogiveyoutimetotakeaction.Itisrecommendedthatyouobtainexperthelpchoosetherightsystemandcorrectlyinstallit.Permissionfromlandownersandlocalauthoritiesmaybeneededpriortoinstallingthesensor.
9.4 Temporary Resistance – Flood warning devices
32
10. Resilience
Resiliencemeasuresareaimedatallowingabuildingtofloodbutconstructingtheinteriorfrommaterialsthatarenotdamagedbywater.Followingflooding,aclean-upwillbeneededbutnotmajordryingandrefurbishment.Correctlyappliedresilienceshouldensurethatnopermanentdamageiscaused,thestructureofthebuildingisprotectedanddryingandcleaningarequickened.
Product type Indicative cost for a single house
Advantages Disadvantages Available products/suppliers Images
Flood alarm £0–£500 Idealwherethereisnoformalfloodwarningservice.24/7monitoring.
Needscarefulinstallation.Needsregulartesting/maintenance.Mayneedtoobtainpermissionfromlandowners/localauthorities.
CampbellScientific.CombinedHarvesters.DynamicLogic.EnvironmentalInnovationsLtd.Floodguards.FloodSafeFloodAlarms.FloodAngel®FloodAlarm.FloodSense.Hydrologic.Isodaq.Revetment–floodalarmsystem.TotalFloodSolutions.UKFloodBarriers.
Hydrologicsensorinstalledonabridgeoverariver.
10.1 Limit water damage
10.2 Remove vulnerable items from flood risk
10.3 Expel water
33
10.1 Resilience – Limit water damage
Description Theseresiliencemeasuresaredesignedtoreducetheamountofdamagecausedwhenwaterentersabuilding.Ideallyapackageofproductsshouldbeusedtolessentheharmthatwaterdoestoabuildingfromaproperty-levelfloodprotectionsurveycarriedoutbyaqualifiedandexperiencedsurveyor.Noparticularactionisrequiredbyyoutomaketheproductworkandsoresiliencewillprotectevenwhileyouareawayfromyourhouseandiffloodingarrivesquicklywithnowarning.Insituationswherefloodwaterisexpectedtoarriveveryquicklyandwithhighdepthandvelocitythebuildingstructuremaybeatrisk.Inthesecasesastructuralsurveyisrecommended.
Flood plan considerationsTheseproductsdonotrequireactivatingtomakethemworkandsoprotectiontoyourhousedoesnotdependuponreceivingandactingonafloodwarning.Notrainingisneededtooperatetheproductsandnolongtermstorageofitemsisrequired.Routineinspectionandmaintenanceoftheresiliencemeasuresishoweveressential.
Creatingafloodplanisimportantforprotectingpeopleandyourpropertyinanemergency.Aswellasstatingwhodoeswhatwhenfloodingisexpected,thefloodplanshouldsaywhattodoina‘worstcasescenario’suchaswhenfloodingisworsethanexpectedandtheriskofpeoplebeingtrappedinthehousewithrisingwater.
1000mmpossible600mmtypicalFlood depth
Flood duration
hoursdaysweeks
Flood onset
Days Minutes
Hours
Flood annual probability
BAR BARBAR
10% 1% 0.1%
Required input of people Low Mid High
Dark blue indicatesstrongapplicabilityofproductsindealingwithflooding,withlight blueindicatingreducingapplicability.
34
Product type Indicative cost for a single house
Advantages Disadvantages Available products/suppliers Images
Water compatible internal walls
Approximately2xcostoftraditionalgypsumorplasterboard
Permanentlyinplace.
Needsgoodqualityworkmanship.Therearestillcleaninganddryingcostsfollowingaflood.Probablyonlycosteffectivetoreplaceexistingaspartofflooddamagerepairwork.Nokitemark.
Aquobex-DragonboardChemicalDPCbelowjoists.Closed-cellinsulation.Lime-plaster.PropertyCareAssociation–waterproofmembrane.Revetment–Dragonboard.Tiling.WaterproofliningforinternalwallsandfloorsfromSafeguardEurope:OldroydXvClearOldroydXpOldroydXv20.DrybaseliquidappliedDPMfromSafeguardEurope.
Water compatible floors Permanentlyinplace.
Needsgoodqualityworkmanship.Therearestillcleaninganddryingcostsfollowingaflood.Probablyonlycosteffectivetoreplaceexistingaspartofflooddamagerepairwork.Nokitemark.
Concrete.Epoxycoating.Tiles.
Aquobex.Revetment.
Water compatible kitchen/bathroom appliances and fixtures.
£100’sto£1,000’s Permanentlyinplace.
Therearestillcleaninganddryingcostsfollowingaflood.Probablyonlycosteffectivetoreplaceexistingaspartofflooddamagerepairwork.Nokitemark.
RKBplastickitchens.SteelplanKitchens.Cheapcarcassesfordisposalafterflood.
Aquobex.Revetment.
SteelplanKitchens
35
Product type Indicative cost for a single house
Advantages Disadvantages Available products/suppliers Images
Water compatible woodwork.
Relativelyinexpensive.Approximately£100perdoor.
Permanentlyinplace.
Therearestillcleaninganddryingcostsfollowingaflood.Probablyonlycosteffectivetoreplaceexistingaspartofflooddamagerepairwork.Nokitemark.
Plasticalternatives.Waterproofpaint.
Aquobex.Revetment.
Water compatible stairs. Approximately2xcostoftraditionalbuild.
Permanentlyinplace.
Therearestillcleaninganddryingcostsfollowingaflood.Probablyonlycosteffectivetoreplaceexistingaspartofflooddamagerepairwork.Nokitemark.
Concrete.Hardwood.Steel.
Aquobex.Revetment.
36
Description Theseresiliencemeasuresaredesignedtoreducetheamountofdamagecausedwhenwaterentersabuildingbyraising,removingorcoveringvulnerableitemstogetthemoutofthewayoffloodwater.Ideallyapackageofproductsshouldbeusedtolessentheharmthatwaterdoestoabuildingfromaproperty-levelfloodprotectionsurveybyaqualifiedandexperiencedsurveyor.Someitemscanberaisedandpermanentlyfixedintopositiononceonlywhileotherswillneedactioneachtimefloodingisexpected.Whereactionisrequirednofloodprotectionwillbeavailablewhenyouareawayfromhome.Insituationswherefloodwaterisexpectedtoarriveveryquicklyandwithhighdepthandvelocitythebuildingstructuremaybeatrisk.Inthesecasesastructuralsurveyisrecommended.
Flood plan considerationsSomeoftheseproductsrequireactiontomakethemworkandsoprotectiontoyourhousedependsuponreceivingandactingonafloodwarning.Sometrainingmaybeneededtocorrectlyoperatetheproductsandlongtermstorageofitemsmayberequired.Routineinspectionandmaintenanceoftheresiliencemeasuresishoweveressential.
Creatingafloodplanisimportantforprotectingpeopleandyourpropertyinanemergency.Aswellasstatingwhodoeswhatwhenfloodingisexpected,thefloodplanshouldsaywhattodoina‘worstcasescenario’suchaswhenfloodingisworsethanexpectedandtheriskofpeoplebeingtrappedinthehousewithrisingwater.
Flood annual probability
BAR BAR
10% 1% 0.1%
Required input of people Low High
10.2 Resilience – Remove vulnerable items from flood risk
Dark blue indicatesstrongapplicabilityofproductsindealingwithflooding,withlight blueindicatingreducingapplicability.
BAR
Mid
1000mmpossible600mmtypicalFlood depth
Flood duration
hoursdaysweeks
Flood onset
Days Minutes
Hours
37
Product type Indicative cost for a single house
Advantages Disadvantages Available products/suppliers Images
Raised utilities Costtorewireahouse,£1k-£4k.
Permanentlyinplace.
Thereisapracticallimittohowhighelectricscanberaised.Nofloodqualitykitemark.
Localelectricians.
Raised kitchen appliances.
Relativelylowcostplinths.
Permanentlyinplace.
Thereisapracticallimittohowhighappliancescanberaised.Therearestillcleaninganddryingcostsfollowingaflood.Nofloodqualitykitemark.
Removable fixtures and fittings.
Relativelylowcost. Rapiddeployment.Inexpensive.
Requiresoccupanttomaintainanddeploy.Nokitemark.
Quickreleasehingesforinternaldoors.RemovableradiatorsfromJaga.
Relocate valuables Zerocost. Rapiddeployment.Nocost.
Requiresoccupanttodeploy.Largeitemsmaybedifficulttomove.
Movevaluablesupstairs.Raisevaluablesontables/plinths.
Water-tight cover for values
Approximately£50percover.
Rapiddeployment.Inexpensive.
Requiresoccupanttostorebagsanddeploy.Nokitemark.
FloodPossessionsProtector.MFCSurvival–Floodbag.
Ref:DEFRAR&Dtechnicalreport,PamBowker,2007
38
10.3 Resilience – Expel water
Description Theseresiliencemeasuresaredesignedtoremovewaterthathasenteredyourhouseeithertoreducethewaterdepthinthebuildingortoquickendryingwhenthefloodinghasended.Ideallyapackageofproductsshouldbeusedtolessentheharmthatwaterdoestoabuildingfromaproperty-levelfloodprotectionsurveybyaqualifiedandexperiencedsurveyor.Pumpingsystemscanbeautomaticandsonospecificactionmayberequired.Clearly,wherethepumpisnotautomaticnofloodprotectionwillbeprovidedwhenyouareawayfromyourhome.Insituationswherefloodwaterisexpectedtoarriveveryquicklyandwithhighdepthandvelocitythebuildingstructuremaybeatrisk.Inthesecasesastructuralsurveyisrecommended.
Flood plan considerationsSomeoftheseproductsrequireactiontomakethemworkandsoprotectiontoyourhousedependsuponreceivingandactingonafloodwarning.Sometrainingmaybeneededtocorrectlyoperatetheproductsandlongtermstorageofitemsmayberequired.Routineinspectionandmaintenanceoftheresiliencemeasuresishoweveressential.
Creatingafloodplanisimportantforprotectingpeopleandyourpropertyinanemergency.Aswellasstatingwhodoeswhatwhenfloodingisexpected,thefloodplanshouldsaywhattodoina‘worstcasescenario’suchaswhenfloodingisworsethanexpectedandtheriskofpeoplebeingtrappedinthehousewithrisingwater.
Flood annual probability
Required input of people
BAR BAR
10% 1% 0.1%
Low High
BAR
Mid
Dark blue indicatesstrongapplicabilityofproductsindealingwithflooding,withlight blueindicatingreducingapplicability.
1000mmpossible600mmtypicalFlood depth
Flood duration
hoursdaysweeks
Flood onset
Days Minutes
Hours
39
Product type Indicative cost for a single house
Advantages Disadvantages Available products/suppliers Images
Sump and pump £50-£2.5k Rapiddeployment.Relativelylowcost.Helpswherearesistanceproductleaks.Canremovefloodwaterinanemergency.
Mustbepositionedandsizedcorrectly.Mayrequireancillarypowersupply.Willneedservicingandmaintenance.Nokitemark.
Floodblock.Floodguards.Revetmentstandalonepump.TotalFloodSolutions.
40
11. Case Studies
JudyGibsonlivesinasmallvillageneartheRiverSevernmidwaybetweenUpton-Upon-SevernandTewkesbury.Shehasexperiencedtwomajorfloodsin2000&2007,thelatterresultinginatwoyearincarcerationinatouringcaravan(withnodirectwater/wastesupply!),whilsther16thcenturycottagewasrestored.Suchwasthedamagetotheoriginaloakbeamsuncoveredfollowingtheremovalofalltheoriginalplasterthattheceiling,staircase,ingle-nookfireplaceandtherearelevationrequiredreplacing.Herinsurancecompanywassympatheticbuttheenormousamountoftime,paperworkandsupervisionofthebuilderscertainlytookitstoll!Judywasdeterminedtoensurethatashercottagerequiredacompleterebuild,itshouldbeconstructedandrefurbishedtoensurethatitwasnotonlyfloodresilient,butwasdesignedtoensurethateverythingonthegroundfloorcouldbemovedtosafetyasquicklyaspossible.
Theprospectofneedingtoliveinacaravanagainforanothertwoyearswasdefinitelynotanoption!Itcanbedone!
11.1 Judy Gibson – A cottage in Worcestershire badly flooded in July 2007 now with resilience measures
Figure 1 Cottageduringfloods
Figure 2 Demolition!
41
Figure 13 Lightweightsettees–easytolift!
Figure 11 Downstairssink–novanityunit
Figure12 Unfixedbookcaseforeasyremoval
Figure 14 TVhungonthewall
Figure 3 Fueloiltankonraisedplinth
Figure 4 Boileronplinth
Figure 5 Demountablewaterproofradiators
byJagaFigure 6
Raisedfireplace
Figure 9 kitchenplinthonchromeleg
&plasticstools
Figure 7 Powderedcoatedsteelcarcasskitchen
unitsbySteelplanFigure 8
Figure8SteelkickboardsonkitchenFigure 10
Raisedfusebox
Theimagesbelowshowworkthatweredonetorestorethecottage:
42
ThelocationisasinglehousenearTadcaster,NorthYorkshire.ThehouseisnotwithinthefloodplainofariverandisnotshowntobeatfloodriskontheEnvironmentAgency’sfloodmap.Thereisnoformaldataavailableforflooddepth,duration,onsetandprobability,soanunderstandingoffloodriskmustbegainedfromlocalknowledge.
Floodinghasoccurredatleast5timesbetween2000and2007duetorunofffromsurroundinghillspassingthroughthislocationinthevillageandoverwhelminganadjacentdrainageditch.Waterdepthhastypicallybeenapproximately300mmbutaninternalwaterdepthofupto900mmhasaffectedpartsoftheinteriorofthehouse.
11.2 A single property with a comprehensive range of flood resistance/resilience measures in Tadcaster
Figure 1 FloodingoutsidethehousenearTadcaster Figure 1 Internalflooding
43
Theownerofthehouseprivatelyfundedalargerangeofresistanceandresiliencetechniques:
• Thegroundfloorswereoriginallyconstructedfromstonebeddedontomortar/earth.Theoriginalfloorwasdugupandtheexteriorwallsweretanked.Anewconcretefloorwithwater-resistantmembranewaslaid.Ceramictileswereusedasthefinalfinishonallgroundfloors.
• Water-resistantcement-basedplasterwascoatedontointernalwalls.
• Allmajorjoinerywasreplacedwithhardwood.
• Raisedelectrics.
• Bespoketemporarydoorguardswereobtainedforfrontandrearoutsidedoorsandsecondarydoorguardsfortheinternaldoorway.
• Theflooroftheconservatorywasraised300mm.
• Newpermanentflooddefencewallswereconstructedatfrontandrearofhouse.
• Sixsubmersiblepumpswereinstalledinthefrontareargardentokeepthewaterleveldownbehinddefencewalls.
• Allthrough-wallserviceconnectionswereraised900mmabovethegroundfloorlevel.
• Adownstairsgravitydrainedtoiletwasreplacedwithapumpedsystem.
• Siliconesealantwasappliedtoexteriorwalls.
• Astockofwaterabsorbingbagsarekeptavailabletoassistwithanyresistancemeasurethatshowsseepage.
Figure 3 Doorguardfittedtotheinternaldoorway
Itisnotknownwhetheraformalfloodplanhasbeenproduced.Aplanwillassesstherisktopeopleandprovideaclearemergencystrategyuponreceiptofawarning(thewarningislikelytobebaseduponMetOfficeinformationandlocalobservation).Theplanwillensuretheongoingeffectivenessofthefloodprotectionmeasuresandwillbeinvaluabletonewownersoftheproperty.
Nofloodincidenthasoccurredsofarsincethemeasureshavebeenputinplace.
44
ChewMagnaisavillageintheRiverChewvalley,southofBristolandwestofBath.TheChewValleyandsurroundingcatchmentsweredevastatedinJuly1968whenasummerstormcausedwidespreaddestructionandfloodingofatleast88properties.Despitetheflooding,acommunitywideflooddefenceschemecouldnotbejustifiedforthevillage.
FloodingatChewMagnacomesaboutfromintenselocalrainfalleventscausingfloodingoftheWinfordBrook(forthenorthernpartofthevillage)andfromtheRiverChew(forthesouthernpartofthevillage).Depthsoffloodingvaryfrom0.02mto1.77mfora4%annualprobabilityeventupto0.09mto1.98mfora0.1%annualprobabilityevent.Foreventswithanannualprobabilityofgreaterthan1%,therearefivepropertieswhicharepredictedtobeinundatedtoadepthof1mormore.97propertieswereidentifiedasbeingwithintheFloodZone2boundary,and69oftheseweretargetedforfloodprotectionmeasuresaspartofaDefrafundedPropertyProtectionGrantScheme.
Surveyorsinspectedeachpropertyandrecommendedgenericmeasuresthatwererequiredtoprotecttheproperties.Measuresthatwereadoptedincluded:
• Doorbarriers(screw-inandslideintypes).
• Airbrickprotection.
• Toiletbungs.
• Sewer/drainnon-returnvalvesandminisinkwastenonreturnvalves.
• Onepropertywasalsofittedwithasumpandpumpsystem.
Thetotalcostoftheprojectwas£325k.Arepresentativeofthelocalparishcouncilwasinstrumentalindrivingthedeliveryoftheprojectforward,liaisingwithlocalresidentsthroughoutdelivery.Thesamepersonwasalsoactivelyinvolvedinworkingwiththecommunityand
managingcommunityfloodplansandalocalFloodActionGroup.TheFloodActionGroupincludesabuddysystemtoensurethatallmeasuresaredeployedattimesoffloods,providingassistanceforexampletoelderlypeoplewholiveinasmallcommunitywithinthevillage,andforpeoplewhoworkawayorareawayonholiday.
11.3 Properties in Chew Magna received temporary flood resistance measures
Figure 1 SilverStreet,ChewMagnain
1968.Thedarklinebytheporchtopmarksthewaterheight
Figure 1 Doorguardfittedtothefrontdoor
Figure 2 Petflapcover
45
ThisprojectwasundertakeninDenshamAvenueandGoughAvenueinthedistrictofDallaminWarringtonaspartofaDefrafundedPropertyProtectionGrantScheme.17propertieswereidentifiedasbeingatfloodriskasaresultofsurfacewaterfromstormswithannualprobabilityofupto5%.Floodinghadpreviouslyoccurredinthisarea5timesbetween2004and2008withinternalfloodingofupto20properties.
PropertysurveyswereundertakenandappropriateBSikite-markedfloodprotectionproductswereimplemented:
• Guardsfittedtofrontandpatiodoors.
• Automaticallyclosingairbricks.
• Airbrickcoversforlowlevelvents.
Thecostoftheprojectwas£32k.ThispartofWarringtonfallswithinanEnvironmentAgencyfloodwarningareaforhighwateronDallamBrook.However,pastfloodsappeartobeasaresultoflocalsurfacewaterandnotdirectlyasaresultofthebrook.Forthisreason,WarringtonBoroughCouncilarelookingintoappointinganeighbourhoodco-ordinatortomanagefloodwarningstoresidentsintheeventofadverseweatherconditions.
11.4 Properties in Dallam received temporary flood resistance measures
Figure 1 FloodinginDallam
Figure 2 FloodinginDallam
Figure 3 Doorguardfixtures
onahouseinDallam
Figure 4 Doorguardfixturesand
auto-closingairbricksonahouseinDallam
46
Thisprojectinvolved45homesatEamontBridgeinCumbriaandwaspartlyfundedbytheDefrafundedPropertyProtectionGrantSchemeandalsobytheEnvironmentAgency.FloodingarisesfromtheRiverEamont.Floodingtopropertiesbeginsduringa5%annualprobabilityfloodeventandlastsapproximately24hours.45propertiesfloodedinNovember2009duringanapproximately1.33%annualprobabilityflood.
Propertysurveyswereundertakenandappropriatefloodresistanceproductswerefittedincluding:
• Guardsfittedtoexternaldoors.
• Airbrickcoversandautomaticallyclosingairbricks.
Thetotalcostoftheprojectwasapproximately£190k.
TheEnvironmentAgencyprovidesaFloodWarningServicewith2hourlead-timeforthisarea,sotheequipmentcanbeinstalledingoodtime.AFloodActionGroupwascreatedinordertopulleveryonetogetherandimplementacommunityfloodplan.
11.5 Properties at Eamont Bridge received temporary flood resistance measures
TheprojectinvolvedasinglepropertyonthebanksoftheRiverSeverninWorcesterthathadconsistentlyfloodedsinceitsconstruction.Severefloodingin2007sawthewaterlevelriseabovethegroundfloorwindowsills.Overtimetheoriginalfloorslabhadbecomecrackedandthedamp-proofmembranehadfailedmeaningthattherewasfrequentwateringressintothegroundfloorwhenevertheriverlevelroseorduringheavyrain.
Theownerofthehousearrangedforaproperty-levelfloodsurveyandprivatelyfundedarangeofresistanceandresiliencemeasures:
• Awatertightmembranewasfittedbehindthefloorandwallsonthegroundfloorwithcavitydrainagelinkedtoasumpandpumpsystem(twinsumpseachwithtwinpumpsforhighdischargeandfail-safe).
• Removablefloodbarriersacrossdoors,windowsandentrypointsbetweenterraces.
• Non-returnvalvesonservicepipes.
TheEnvironmentAgencyprovidesaFloodWarningServiceforthisarea,sothetemporaryfloodresistancemeasurescanbeinstalledingoodtime.Aninformalfloodactiongrouphasbeencreatedsothatlocalresidentscanhelpeachotherwiththefloodbarriers.
11.6 A single property in Worcester with a range of resistance and resilience products
47
Figure 1FloodingatthepropertyinWorcester
Figure 2 Water-proofmembraneswithoneof
thesumpsreadyforpumpinstallation
(Source:TritonChemicals)
48
Afterthearduoustaskofclearingseaweedandotherdebrisfollowingastormsurgeandwindassistedtidalfloodoftheircarparkin2008,agroupofneighboursdecidedtoinstallafloodbarrier.Thebarrierwasinstalledlaterthesameyearandfortunately,ithasonlybeenneededonce–despiteextremerainfallandtheimmediateareasufferingextensiveflooding.
Oneofthecottageownerscommented:“Ourhomewasbuiltaround20yearsagoand,whilstitisnotsusceptibletothefloodingthatthelocalareahasexperiencedinrecentyears,thecarparkinwhichIandmythreeneighbourskeepourcarsbecomesfloodedaboutonceeveryfouryears.Thewaterrisestoaboutfourincheswhich,althoughdoesn’tnecessarilysoundashighasfloodwatersinotherareasofthecountry,withwavesontopitismorethanenoughtocausearealmesswithallofseaweedandgrasscuttingsloshingaroundinChichesterHarbourbeingdumpedinfrontofourcottages.”
“Oncethefloodwaterfinallyrecedes,thecarparkisfullofdebrisandisinaterriblemess;ittakeshoursforustobeabletostartusingthecarparkagainandisarealnuisance–Icanonlyimagehowutterlyterribleitmustbeforpeopletoexperiencethisintheirhomes.
“WhenthecarparkwasatriskoffloodinginOctober2012,weweredelightedtobeabletorelaxafterquicklyerectingtheFloodControlInternationalbarrier.Theimpacthasbeenquiteincredible;onlyadropofwaterescapedbeneaththebarrierandcameintoourcarpark.Itisquiteextraordinaryseeingthebarriersinaction,literallyholdingbackthefloods.IfIhadn’tseenitformyselfIwouldn’thavebelievedtheywouldbequitesoeffective.
“Itwasabsolutelymoneywellspent.Ihavenoconcernsnowwhatsoeverofourcarparkflooding,regardlessofhowhighthestormsurgeis.Iwouldn’thesitatetorecommendtohomeownersthattheyinstallfloodpreventionandprotectionmeasurestotheirhomes;theyreallydoworkandcansaveanenormousamountofheartache,disruptionand,ifhomesareatrisk,alotofmoney.”
11.7 A Car Park in Chichester – Installing Flood Barriers Successfully Keeps the Water Out
Figure 1 PostmaninBoshambraves
thefloodwaters
Figure 2 Floodbarrierinaction
49
Absorbeez is part of the Action Dry Group:
ActionDryGroupPOBox139UpminsterEssexRM142YDEactiondry@mac.comWwww.absorbeez.com
AquaFence Ltd.
TheWorkshopBearsLaneSwaffhamAlcesterNorfolkPE377QBT 01760722750 [email protected]
Aqua-sac is part of AET:
AETPOBOX4706SheffieldS179BUNationalSalesNumber:[email protected]
Aquobex Ltd
Building69BuildingResearchEstablishmentBucknallsLaneGarstonWatfordHertfordshireWD259XXT01923518582Eenquiries@aquobex.comWwww.aquobex.com
CARO FLOOD DEFENCE SYSTEMS
EdgeBarn11MarketHillRoystonHertfordshireSG89JNT01763244446F01763244111Einfo@caro.co.ukWwww.caro.co.uk
Combined Harvesters Ltd.
BritanniaHouseDockRoadBirkenheadWirralCH411DFT01516390880F01516392212Einfo@combinedharvesters.co.ukWwww.combinedharvesters.co.uk
Defence Doors LtdFairwaysHouseThornholmeDriffieldYO254NNT01262490219E [email protected]
Dutchdam B.V.
BoddensHosangweg84-2481LAWoubruggeTheNetherlandsT0031(0)[email protected]
Easifit Ventguard
Flash Flood Doors Limited
Unit6,BevanCloseFinedonRoadIndustrialEstateWellingboroughNorthamptonshireNN84BLT01162672408Einfo@flashflooddoors.co.ukWwww.flashflooddoors.co.uk
Flood Ark Ltd
TheForgeTheStreetLyngNorwichNR95QZT01603879977F01603879964Einfo@floodark.co.ukWwww.floodark.co.uk
Flood Control and Flood Control International
KilworthyParkTavistockDevonPL190FZT01822619732Eenquiries@floodcontrol.co.ukWwww.floodcontrol.co.uk
12. Directory of flood protection product manufacturers and suppliers featured in this handbook
50
Floodgate Limited
49/51LammasStreetCarmarthenWalesSA313ALT01267234205F01267232752Esales@floodgate.ltd.ukWwww.floodgate.ltd.uk
Flood Guards Systems Ltd.
Unit8AKennetWeirBusinessParkArrowheadRoadThealeBerksRG74AZT08455000077F08455000088Esales@floodguards.comWwww.floodguards.com
Floodguard UK Ltd
T08000735455F01257255985Eadmin@floodguarduk.co.ukWwww.floodguarduk.co.uk
Flood Plan
ApexHouseHavannahStreetCheshireCW122AGT01260289089Einfo@floodplan.co.ukWwww.floodplan.co.uk
Flood Safe Flood Alarms
PC-QSolutionsLtdT/aFloodSafeCambrianHouse1CambrianPlaceLlanidloesPowysSY186BXEinfo@floodalarms.co.ukWwww.floodalarms.co.uk
FloodSense
TheWorkshopBearsLaneSwaffhamNorfolkPE377QBT01760722758F01760724826Einfo@floodsense.co.ukWwww.floodsense.co.uk
Floodsax by Environmental Defence Systems Ltd
FloodSentry Limited
CoachHouse1CorneyburyFarmOfficesRoystonRoadBuntingfordHertsSG99RST01763272455F01763272455Esales@floodsentry.comWwww.floodsentry.com
Floodtite Systems Ltd
500TheBroadwayMuswellHillLondonN101BTT02084420872Esales@floodtite.comWwww.floodtite.com
FloodWall
T01923859994F01277637590Einfo@floodwall.org.ukWwww.floodwall.org.uk
Flood Wall Systems
T08450959990Ebob@floodwallsystems.co.ukWwww.floodwallsystems.co.uk
Flowstop Ltd
1KingdomAvenueNorthacreIndustrialEstateWestburyWiltshireBA134WET01373858234F01373858235E [email protected]
51
Hydro-Logic Ltd and Isodaq
OldGrammarSchoolChurchStreetBromyardHerefordshireHR74DPT01885483789F01885483792Epwebster@hydro-logic.co.ukWwww.hydro-logic.co.uk
Icopal - Head Office
BartonDockRoadStretfordManchesterUnitedKingdomM320YLT01618654444F01618642616Einfo.uk@icopal.comWwww.icopal.co.uk
Kiltox
Unit6ChiltonianIndustrialEstate203ManorLaneLeeLondonSE120TXT08451662040F08451662050Einfo@kiltox.co.ukWwww.kiltox.co.uk
Marley Plumbing and Drainage
LenhamMaidstoneKentME172DET01622858888F01622858725Emarketing@marleyext.comWwww.marleyplumbinganddrain-age.com
MFC Survival Ltd
NavalYardTonypandyRhonddaCynonTaffCF401JST01443433075F01443420448Esales@mfc-survival.comWwww.mfc-survival.net
MISSION Rubber UK Limited
Units4+5AtlasBusinessParkStarnhillCloseEcclesfieldSheffieldS359TGT01142570040F01142571122Esales@missionrubber.co.ukWwww.missionrubber.co.uk
Multi-Flood Solutions
SouthfieldsBorastonLaneTenburyWellsWorcestershireWR158RBT01584819233F01584819130Einfo@multifloodsolutions.co.ukWwww.multifloodsolutions.co.uk
Newlands (forFloodBuddyandVentBuddy)
NewlandsConservatories&GardenBuildingsEveshamRoadNortonEveshamWorcestershireWR114TWT01386446089F01386446089Einfo@floodybuddy.comWwww.m0rad.demon.co.uk
Nanoshell
3MarySeacoleRoadTheMillfieldsPlymouthDevonPL13JYT08458388648Einfo@nanoshell.co.ukWwww.nanoshell.co.uk
Revetment Flood Protection
7TheCoachHousesHenley-in-ArdenWarwickshireB955FNT08448044046Eenquiries@revetment.uk.comWwww.flood-guards.co.uk
Safeguard Europe Ltd
RedkilnCloseHorshamWestSussexRH135QLT01403210204Wwww.safeguardeurope.com
Snorkel Vent is a trading name of Donite Plastics Ltd:Donite Plastics Ltd
PrimaBusinessPark280ComberRoadLisburnNorthernIrelandBT276TAT02892639995F02892639996Einfo@snorkelvent.co.ukWwww.snorkelvent.co.uk
52
Steelplan Kitchens
WealdstoneRoadKimptonIndustrialEstateSuttonSurreySM39RWT02082542018F02086415026Esales@steelplan.comWwww.steelplan.com
Tilt Dam Ltd
T01494672323T07841830393T01903883276Esales@tiltdam.co.ukWwww.tiltdam.co.uk
Total Flood Solutions
Units12LlanelliGateLlanelliSA148LQT08454567175F01554759866Einfo@totalfloodsolutions.comWwww.totalfloodsolutions.com
Tubewall from:
ProtectahomeLtdSalisburyHouseTheSquareMagorCaldicotGwentNP263HYT08456011980Esales@Tubewall.co.ukWwww.tubewall.co.uk
Triton Systems
Units3-5CrayfordCommercialCentreGreyhoundWayCrayfordKentDA14HFT01322318830F01322524017Wwww.triton-chemicals.co.uk
UK Flood Barriers Limited
9aWassageWayHamptonLovettIndustrialEstateDroitwichWorcestershireWR9ONXT01905773282F01905775037Einfo@ukfloodbarriers.co.ukWwww.ukfloodbarriers.co.uk
Watertight International Ltd
NorthLaneFoxtonMarketHarboroughLeicestershireLE167RFT01858546810Eenquiries@watertightinternational.comWwww.watertightinternational.com
Whitehouse Construction Co. Ltd
BlenheimRoadAshbourneDerbyshireDE61JUT01335344000F01335346546Wwww.whitehouseconstruction.co.uk
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13 Useful contacts
TheEnvironmentAgencyoffersadviceonfloodprotectionmeasuresandfloodplanningandprovidesmanyusefulguidesandtemplates:www.environment-agency.gov.uk
MetOffice:www.metoffice.gov.uk
DEFRAhasfundedseveralresearchprojectsintofloodriskmitigation:www.defra.gov.uk
TheinsurancecompanyAVIVAhaveproducedawebsitethatgivesusefuladviceforpropertylevelfloodresilience:www.floodresilienthome.com
TheFloodProtectionAssociationpromotestheinterestsofmanufacturersandinstallersoffloodprotectionequipment:www.thefpa.org.uk
TheCharteredInstitutionofWaterandEnvironmentalManagement(CIWEM)maintainaprofessionalsdirectorywherealistoffloodriskconsultantscanbefound:www.ciwem.org
TheNationalFloodForumprovidessupportandadvicetocommunitiesandindividualsthathavebeenfloodedorareatriskofflooding,whichincludesthe‘bluepages’directoryoffloodprotectionproductsandserviceswww.floodforum.org.uk
MaryDhonauhasproducedawebsitethatprovidesadviceonfloodprotectionproductsandmethods:www.marydhonau.co.uk
ThePropertyCareAssociationprovidesinformationaboutfloodrestorationontheirwebsite:www.property-care.org
FloodPlanUKisawebsitethatprovidesadviceonprotectingyourhomeandplanningforflooding:www.floodplanuk.org
TheRoyalInstitutionofCharteredSurveyors(RICS)hasproducedausefulguidetofloodingforthepropertyownerjustfollowthelinktousefulguidesontheUKwebsite.RICSalsomaintainalistofcharteredsurveyors:www.rics.org/uk
RABConsultantsLtdcanprovideadviceandassistanceonfloodriskandproperty-levelprotectionsurveys:www.rabconsultants.co.uk
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