Overheating in UK homes: occurrence, causes and solutions...
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Overheating in UK homes: occurrence, causes and solutions Bill Gething Sustainability + Architecture Good Homes Alliance: New Homes and Our Health University of Sheffield July 2017
Transcript of Overheating in UK homes: occurrence, causes and solutions...
Overheating in UK homes:
occurrence, causes and solutions Bill GethingSustainability + ArchitectureGood Homes Alliance: New Homes and Our Health
University of Sheffield July 2017
Source: Met Office 2014 Report
Data from HadCRUT4, Met Office and Climatic Research Unit, UEA
Photograph: Aurelien Guichard
Hotter drier summers
Wetter warmer winters
Extreme events more likely
Sea level rise
Climate change headlines for the UK
Twin Challenges of Climate Change
Mitigation Reduce emissions
Adaptation Design for a changing climate
Exploit the overlap
Avoid the conflicts.
Comfort: a balancing act
People
Ventilation
Conduction
Equipment
Lighting
Solar gain
Active
he
atin
g
WinterRecent construction
Jul Aug Sep Oct Nov Dec Jan Feb Mar JunApr May
Comfort: a balancing act
Solar gain
Lighting
Equipment
People
Ventilation
Conduction
Active h
eating
Ventilation
Conduction
Active
he
atin
g
WinterNew construction
Jul Aug Sep Oct Nov Dec Jan Feb Mar JunApr May
Comfort: a balancing act
Solar gain
Lighting
Equipment
People
Ventilation
Conduction
Ac
tive
Co
olin
g?
SummerNew construction
Conduction
Solar gain
Comfort: a balancing act
Solar gain
Lighting
Equipment
People
Ventilation
Conduction
Minimise
Minimise
Control
Control
Fabric storage
+ Climate change
SummerNew construction
Overwhelmed?
Consider
Modelling as a design tool … not just for verification
Gale and Snowden
CIBSE (UKCIP02) 14 locations
PROMETHEUS (UKCP09) Exeter 43 locations
CIBSE (UKCP09) 14 locations
COPSE (UKCP09) Manchester 2 (+) locations
Current and future weather files for dynamic simulation
Design Summer Year 3rd hottest year in a 20 year period
2020s 2050s 2080s
Su
mm
er
me
an
da
ily m
axim
um
te
mp
era
ture
(ºC
)
32
30
28
26
24
22
20
Which Climate? CIBSE/ UKCIP ProCLiP charts
Baseline (1961-90)
Central estimate
Likely
33%
67%
Very Likely
10%
90%Me
diu
m
Lo
w
Hig
h
London, Tokyo, New York threatened
Islington
Primary DSY
Secondary DSY4º
2º
Land Surface Temperature, 12 July 2006, 21.00 UT ASTER satellite image
Urban Heat Island
Heathrow
Gatwick
+ Microclimatic effects
Green & blue space
Shading
Street canyon
Street orientation
Albedo
Density
Heat emissions.
Holborn
Hot weather patterns – the fair test?
‘76 ‘89
‘03
CIBSE TM49
DSY1 Moderate
DSY2 Intense
DSY3 Long
What to look out for…. Canary Properties
Single aspect flats
Lots of glass
Windows with limited or poorly controlled ventilation
Noisy and/ or dense surroundings
Communal heating without ventilation
SAP Appendix P assessment with all the boxes ticked
Top floors, particularly with poor insulation
Retrofitting insulation without dealing with ventilation
Crowded properties
Vulnerable residents.
Germany: max % to avoid calculation
SAP Consultation: Appendix P Jan 17
“ ….should not be depended on by designers to ensure a given
design will provide thermal comfort”
Ref: Overheating in new homes: A review of the evidence’
NF46, NHBC Foundation, Nov 2012
Window Options (2012): Trickle vent
Slightly open
Open half time
Fully open.
Yes/ No questions:
Noise nuisance (Planning, proximity to main road etc, airport)
Security risk (Easily accessible (AD Q); secure night vent?)
If Yes, only trickle vent allowed
Curtain, blind and shutter factors changed.
Launched 28 June
“Predominantly Natural” and Predominantly Mechanical” ventilation
Overheating criteria for both (mix of adaptive and threshold (beds))
Standard occupancy and internal gains (variety of home types)
24 hours occupancy to highlight fabric issues.
CIBSE TM59
2020s 2050s 2080s
Su
mm
er
me
an
da
ily m
axim
um
te
mp
era
ture
(ºC
)
32
30
28
26
24
22
20
Which Climate? CIBSE/ UKCIP ProCLiP charts
Baseline (1961-90)
Me
diu
m
Lo
w
Hig
hDSY1Moderate 1989
(London)
DSY2Intense 2003
DSY3Long 1976
CIBSE TM59
Launch: 28 June
“Predominantly Natural” and Predominantly Mechanical” ventilation
Overheating criteria for both (mix of adaptive and threshold (beds))
Standard occupancy and internal gains (variety of home types)
24 hours occupancy to highlight fabric issues
DSY1, 2020s, high emissions 50th percentile
Treatment of communal spaces and hot water distribution
Sample size for assessing large developments
Blinds only if part of architectural solution (with and without requ’d).
Guidance NHBC Foundation & Zero Carbon Hub
Guidance Zero Carbon Hub
http://www.zerocarbonhub.org/recent-publications
