Sustainable Roofing – Learning From Case Studies to Manage Your Roofing Investment”

Brian Boomars, P.Eng.

Executive Director

SUSTAINABLE ROOFING – LEARNING FROM CASE STUDIES

TO MANAGE YOUR ROOFING INVESTMENT

Presentation for APEGBC – Richmond/Delta Branch

January 21, 2015

AGENDA

• About the speaker • Functions of a Roof • Defining sustainability • Case Study: School

o Roof Condition Assessments – Setting the Baseline

o Other Considerations: Seismic, Rooftop Fall Protection, Mechanical Systems, Skylights

o Value Engineering – Adding value, not removing it!

o Defining the Plan o Design and Tendering o Quality Assurance during Construction o Construction Photographs o Warranties

ABOUT THE SPEAKER

Brian Boomars, P.Eng. • Executive Director & Branch Manager of IRC

Building Sciences BC regional office. • Managed projects as large as $140 million,

throughout Canada. • Projects include: building envelope rehabilitations,

new construction, major building additions, paving restorations and roofing restorations.

• Member of the Association of Professional Engineers of Geoscientists of BC (APEGBC), the BC Building Envelope Council (BCBEC), RCI Inc. (formerly the Roofing Consulting Institute), and the Condominium Homeowners Association (CHOA).

WHAT ARE THE FUNCTIONS OF A ROOF?

• Keep out water • Air / vapour barrier • Thermal insulation • Expansion joints • Fire rating • Aesthetics • Public space, parking and

maintenance access • Storm water management • Gardens

IF THERE IS NO WATER DRIPPING INSIDE THE ROOF IS OK

RIGHT? – NO! THAT IS ONLY ONE INDICATOR OF A FAILURE. • Different roofs leak differently, some

absorb a lot of water and don’t look leaky. • Wet insulation has reduced thermal

resistance. • Wet roofs can cause structural damage

(wood rot, deck corrosion, fastener corrosion).

• Roof membrane splits within a pond of water can cause a flood in the building, not just a leak.

• Ponding water is heavy and can cause damage due to weight.

• Roof systems can get mouldy. • Beware of asbestos and lead when

planning restorations. • Ignoring a failed roof can double (or more)

repair costs later due to damage to other components.

SUSTAINABILITY – WHAT IT MEANS TO YOU

• LEED Points – generally new construction or major renovations.

• Corporate Initiatives – standards for maintenance / replacement projects / new construction.

• Municipal Initiatives such as “reflective, vegetative, or solar power requirements.” • Applies to permitted jobs, not generally roof replacement. • Roof replacement is normally classified as “maintenance”

by municipalities, but not always. • Building Operations normally focuses on long term value.

• Minimize life cycle costs. • Minimize maintenance. • Minimize occupant complaints. • Minimize heating costs. • Safety: fall protection, maintenance access, restricting

unauthorized access.

SUSTAINABILITY – CONSIDER THESE…

• Reflective roofs – Are they really a good thing? • Membrane thermal cycling • Roof assembly drying • Reflective performance over

time • Green roofs – Intensive &

extensive • Cost to establish vegetation • Storm water absorption in

winter • Membrane Thermal Cycling • Tracing Leaks

• Eco-active roofing – It cleans the air! • Performance when dirty?

SUSTAINABILITY – CONSIDER THESE…

• Low VOC products – Better for the environment, but does it last? • Performance in cold damp conditions • Installer and occupant Health and Safety

• Local manufacturers – Reduced transportation energy and emissions

• Recyclable materials – Avoiding the landfill • What can be re-used or re-manufactured? • Recycling options vary geographically. • Anticipate recycling options for the future, and incorporate into your

roof. • Do it once! – Planning the “other stuff” that affects the roofing system.

• Seismic upgrades, fall protection, skylights, etc. can be done at a substantial cost. reduction when the roof is “open”; often saving 25% or more.

ROOF CONSULTING QUALIFICATIONS

• Roof Consulting is generally NOT regulated, so YOU need to decide what qualifications YOU want.

• RCI Inc. (formerly the Roofing Consultant Institute, which has expanded into Waterproofing and Building Envelope) is the generally accepted authority for Roof Consulting professional designations. o RRC – Registered Roof Consultant

• Not very common in BC, but is increasing. • Not generally required by clients. • Not a legislated designation like Engineers, or Architects

and therefore cannot sign Letters of Assurance for permitted work. • RRC’s may not have roof installation experience and therefore not

qualified as an RRO. o RRO – Registered Roof Observer

• Common qualification in BC for roof inspectors. • Often a requirement of clients. • Accepted as a Professional Witness in litigation.

ROOF CONSULTING QUALIFICATIONS

• QAO RCABC accepted Inspector o Quality Assurance Observer (QAO) o RCABC tests and interviews applicants before

accepting. o Experience with roofing applications is a must.

• TQ – Trade Qualified Roofer (Red Seal) o Journeyman tradesman normally attained via

apprenticeship. o Flat roofing (waterproofing) is one trade. o Sloped roofing (watershedding shingles) is a

separate trade. o Caution: TQ is not mandatory by Code so YOU

need to decide what YOU want. • Architect, Engineer, Technologist, Experienced Roofer, and self

proclaimed experts. o P.Eng. required in some instances.

ROOF CONDITION ASSESSMENT – SETTING

THE BASELINE

The objective of a Roof Condition Assessment is to review the condition of the roof assemblies and related components, to assess their existing condition, estimate remaining service life, and to make recommendations on future repair and/or replacement.

The site investigation consists of a thorough examination of the roofing components by Registered Roof Observers (RRO) or equivalent in order to establish their current condition in addition to identifying areas requiring remedial attention. Membrane, perimeter flashing details, caulking, drainage, and surface anomalies are visually examined to identify signs of failure and potential future problem areas.

A roof plan is prepared showing all the designated roof areas, their relative elevations, deficiencies and other pertinent information.

Recommendations for remediation, budgetary costing estimates for corrective/replacement work are provided at the end of the report.

ROOF CONDITION ASSESSMENT

Scope of Work The scope of work includes the following elements and techniques: 1. On-site visual inspection of all selected roof

areas. Visual record of potential sites for water entry into the building or other defects.

2. Interviews with appropriate staff, in conjunction with document review, if available.

3. Core-cut testing, relating to roofing system assembly.

4. Moisture probe analysis at core-cut locations utilizing the Delmhorst Moisture Meter for the purpose of moisture verification at the following locations: a. Roof Inter-ply System b. Insulation within the sub roof system.

5. Electronic Impedance Scanning (Tramex) 6. Thermographic Scanning (Infra-red) 7. Leak detection systems / scanning

• Systems can be temporary or permanently installed.

Roof Area Estimated Age

(In Years) Deck Type

Vapour

Retarder Insulation Membrane System Surface

Perimeter

Details

Approximate Thermal

Resistance Above Deck

(Insulation Dry)

1.1 2 No Core Taken No Core Taken No Core Taken 2 Ply Mod. Bit. Granules Parapets and

Walls Unknown

1.2 32 No Core Taken No Core Taken No Core Taken Metal Cladding Prefinished Parapets and

Walls Unknown


Walls Unknown


Walls Unknown

3.1 14 Recover

32 Original Concrete None

2 Layers 0.5” Fiberboard

5” Expanded Polystyrene

2 Ply Mod. Bit.

4 Ply Organic B.U.R. Granules

Parapets and

Walls 16

3.2 8 Steel None 1” Polyisocyanurate

5” Expanded Polystyrene 2 Ply Mod. Bit. Granules Parapets 18

3.3 14 Recover




2 Ply Mod. Bit


Parapets and

Control Joints 16

3.3 14 Recover




2 Ply Mod. Bit.


Parapets and

Control Joints 16

3.4 17 Recover




2 Ply Mod. Bit.


Walls, Parapets

and Control

Joints

16

3.5 14 Recover




2 Ply Mod. Bit.


Parapets and

Control Joints 10

3.6 14 Concrete None 0.5” Fiberboard

8.5” Expanded Polystyrene 2 Ply Mod. Bit. Granules

Walls and

Control Joints 27

4.1 14 Concrete None None 2 Ply Mod. Bit. Granules Parapets 0

5.1 17 Recover




2 Ply Mod. Bit.


Walls, Parapets

and Control

Joints

16

5.2 1 No Core Taken No Core Taken No Core Taken 2 Ply Mod. Bit. Granules Parapets n/a

6.1 8 Concrete None

3/8” Gupsum



2 Ply Mod. Bit. Granules Parapets 22

6.2 14 Recover

32 Original Steel None


1.5” Expanded Polystyrene

2 Ply Mod. Bit.


Parapets and

Control Joints 6

7.1 14 Recover




2 Ply Mod. Bit.


Parapets and

Control Joints 19

SAMPLE OF ASSESSMENT SUMMARY TABLE

????????? School

?????, ?????, British Columbia

Proposed Roofing Maintenance and Replacement Forecast

Estimated expenditure by year in current dollars

Recommended Action 2012 2013 2014 2015 2016

Annual Maintenance and Emergency

Repairs Allowance $ 5,000 $ 4,000 $ 2,000 $ 1,000 $ 1,000

Repairs Roof Areas 1.1, 1.2, 2.2, 3.2,

3.3C, 6.1 and 7.1

4,584 Sq. Ft.

$ 3,000

Replace Roof Area 3.3, 3.3A, 3.3B 3.4

and 5.1

23,341 Sq. Ft.

$ 466,000

Replace Roof Areas 3.1, 3.5, 3.6, 4.1 and

6.2

9,975 Sq. Ft.

$ 330,000

Skylights Skylight 3

1,552 Sq. Ft. $ 115,000

Skylights 1 and 2 and Entry

936 Sq. Ft. $ 70,000

Total Estimated Expenditures $ 589,000 $ 404,000 $ 2,000 $ 1,000 $ 1,000

Supplementary Replace Roof Area 5.2

(Library)

7,501 Sq. Ft.

$ 150,000

SAMPLE OF BUDGET FORECAST

ROOFING CONDITION ASSESSMENT

Photograph 6: Roof Areas 2.1 and 2.2 – These roof areas are canopy roofs situated at the north side. They are covered with metal cladding and are serviced by built-in gutters, scupper drains and downpipe. Minor debris was located

within the gutters.

Photograph 8: Roof Area 3.1 – Debris in the form of abandoned equipment was observed on the roof

area. Advanced alligatoring of the membrane was evident throughout the roof area.

Photograph 10: Roof Area 3.1 – Mastic and granules was omitted at the base of all plumbing stack flashings. The

plumbing stacks are typically lower than the flashings resulting in points of water entry where indicated by the

arrow.

Photograph 16: Roof Area 3.3 – Curbs were omitted at this exhaust fan assembly resulting in likely points of water

ingress. High Tramex meter readings were detected around this exhaust fan, indicating moisture beneath the membrane.


Photograph 17: Roof Area 3.3 – Concrete paver was installed without membrane protection.

Photograph 19: Roof Area 3.3 – Test probes indicated high moisture content within both roofing systems at the core

cut location.

Photograph 30: Roof Area 3.4 – Mastic applied in the pitch pockets is low resulting in water within the pockets.

Photograph 49: Roof Area 5.1 – Exposed fasteners were observed on the metal cap flashing resulting in points of

water entry. Membrane flashing was omitted resulting in openings along the side lap of the cap membrane at the

transition.


Photograph 57: Overview of Roof Area 5.2 (Library) – This roof area is not included in the contract.

Photograph 58: Overview of Skylight 1 – This skylight is located on Roof Area 3.6 at the southeast corner of

the building. It was constructed using the T-bar system.

Photograph 60: Skylight 1 – Significant moisture resulting in organic growth is visible on the glass.

Photograph 66: Skylight 2 – The skylight flashing requires replacement.

Photograph 70: Skylight 2 – Big opening at the bottom of the skylight.

The 2 year old “skinned” roofs were further investigated…

Roof Areas 4.2, 4.3 and 5.2 are a new 2 ply modified bitumen overlay roof installed approximately 2 years ago. Information provided by the roofer and the facilities manager indicated the roof was torn off to the fiberboard layer and a new modified bitumen membrane roof installed. All new metal flashing was installed. The electrical and gas service line flashings were reused. The existing steel deck was not reportedly viewed at the time of the re-roof as the existing insulation was not removed.

Photograph 1: Core sample number 1 was performed at the north corner of the south west wing of the library roof. Some corrosion of the

steel deck was observed. (RA 5.2)

Photograph 3: A moisture reading of 17.6 percent was documented in the insulation at the steel

deck level. This is a relatively low level of moisture but is enough to promote the deck

decay shown in these photos.

Photograph 6: A reading of 16.3 percent moisture was observed at this location.

ROOFING CONDITION

ASSESSMENT

• Fifteen core samples were performed. • Steel deck substrate was in good condition at approximately one half of the locations

observed. • Corroded steel deck was recorded at core sample locations 1, 2, 6, 9, 10, 11 and 13

with the most Severe at locations 1, 2 and 9. • The steel deck can be repaired by the removal of the existing corrosion and the

treatment of the steel by means of rust inhibiting primer and corrosion resistant paint. • Once the existing roof is removed to the steel deck level a complete review can be

performed and directions for remediation issued. • Fastener pull out testing can be done to verify deck integrity. • The moisture content recorded in the roofing components was high in several areas.

• Phenolic Foam insulation that was used in this application is known to be detrimental to galvanized steel as it reacts with water to create acid.

• Metal roof deck replacement is likely not required; however, some need for localised replacement may be identified once the removal of the roof is complete.

Roof Area Recommended

Actions

Estimated costs

per sq. ft.

Estimated

Costs

Roof Area 5.2,

7501/sq. ft.

Full roof

replacement $18.00/sq. ft. $135,018

Roof Area 5.2,

7501/sq. ft.

Steel Deck

Reconditioning $3/sq. ft. $22,503

Roof Area 4.2,

336/sq. ft.

Full roof


Roof Area 4.2

336/sq. ft.

Steel Deck

Reconditioning None None

Roof Area 4.3

182/sq. ft.

Full roof


Roof Area 4.3

182/sq. ft.

Steel Deck

Reconditioning None None

Estimated Total Expenditures $166,845

FINDINGS ON SKINNED ROOF

COMPLEMENTARY ASSESSMENTS

HVAC ASSESSMENT RESULTS

• HVAC system assessment by IRC • Fall Protection Assessment by IRC • Seismic assessment by Genivar (now WSP) • Building Envelope assessment by IRC

1. Repairs / Replacement (0-2 Years): $119,400 2. Repairs / Replacement (2-5 Years): $170,700 3. Repairs / Replacement (5-10 Years): $2,000 4. Repairs / Replacement (10-20 Years): $453,700 5. Repairs / Replacement (20 + Years): $9,000 6. Refer to the Summary of Recommendations Table for each unit as to specific

recommended repairs and schedule 7. Budget for progressive replacement of R-22 refrigerant systems over next 10 years

$30,000 8. Code compliance – Rooftop unit restraint and gas piping dirt traps - $17,000

• Replacement of rooftop equipment and curbs was coordinated with roof

replacement – saves money • Roofer installs curbs – better quality and lasts longer • HVAC uses roofer’s crane – saves money

IMPACT ON ROOF PROJECT?

Assess access to Rooftop: • Ladders secure and ANSI 14.3 compliant. • Access hatches and door secured and operational. • Transition to safe area of the roof (greater than 4

metres from the edge) is protected from falls.

Follow WorkSafe BC hierarchy for Fall Protection Assessment: 1. Hazards eliminated where possible. If you don’t need to be within 4 metres

of an edge or on a slippery slope then there is no hazard. 2. Install guardrails to protect from edges. 3. Use fall restraint, normally via roof anchors and lifelines. 4. Use fall arrest, via roof anchors and lifelines. 5. Other measures (control zones, safety monitor, procedures, etc.)

• Guard around hatches, skylights, etc. if fall hazard is more than 10 feet. • Skylights engineered to withstand guardrail forces need not be guarded. • Add ladders / steps / etc. as required to safely transition between

different roof elevations.

FALL PROTECTION

• Have a plan before accessing the roof. • Building operator to provide details of fall protection equipment (if

any) that is available for use. • Ensure roof anchors are certified (within the past 12 months) prior

to use. • Anchors may be re-certified by Professional Engineers, and need NOT

be certified by the original installer.

USING FALL PROTECTION

BUILDING ENVELOPE CONDITION ASSESSMENT

• Identify roofing design elements impacted by planned envelope work. • Parapet details. • Roof anchors for

accessing the façade.

SEISMIC ASSESSMENT

SEISMIC ASSESSMENT

• Identify work to be completed while the “roof is off” • Wood sheating overlay. • Wall to roof connections. • Drag struts and bracing. • Roof deck securement upgrades. • Decide if the “Roofer” should be contracted to perform the work.

DEVELOPING THE ROOFING PROJECT PLAN

• Identify concurrent work • Seismic upgrades • Skylight replacement • HVAC unit replacement • Guardrails / anchors / ladders

• Hazardous materials assessment – we assist Hazmat contractor with roof cuts

• Determine Thermal Insulation Requirements (R value) • Roof drainage assessment and overflow scuppers • Review structural capacity

• Is the new roof more weight? • Verify the capacity of deck for roof fastening • Determine wind uplift requirements

• Identify maintenance access requirements & fall protection • Identify building envelope issues to be addressed

• May want to accommodate transitions for future wall upgrades • Evaluate roofing system options

ROOFING PRE-DESIGN

• Overlay existing roofing with SBS Modified Bitumen

• Flood coat overlay • EPDM (rubber) • TPO / PVC • Built up roof (BUR) • SBS Modified Bitumen • Hot rubber • Liquid applied coating • Expansion joints • Asphalt shingles / laminated shingles • Metal (exposed fastner / snaplock /

standing seam) • Tile (slate / concrete / clay / metal) • Cedar shingle or shake

ROOF MEMBRANES CONSIDERED (VALUE

ENGINEERING)

• Fastening (mechanical, adhered, ballasted) o Watch out for damage to pipes and conduits from fasteners

• Drainage (structural vs sloped insulation package) • Insulation (EPS / XPS / polyiso / mineral wool / fiberglass)

o EPS is low cost, low strength, voids hold water, R3-6 o XPS is high cost, high strength, absorbs moisture with long term water exposure, R5

LTTR o Polyisocyanurate is medium cost, medium strength, may absorb moisture, R5-7 LTTR o LTTR = Long Term Thermal Resistance o Mineral wool is high cost, semi-rigid, heavy, non-chemical, sound absorbing,

hydrophobic, R3-8 • R value

o Short vs long term, polyiso decreases over time

o Thermal bridging • Fire rating

o Thermal barrier required at deck could be gypsum, polyiso or concrete

• Safety o Slip resistance of surface o Contrasting colour edges

• Deconstruction cost and environmental impact

VALUE ENGINEERING – OTHER CONSIDERATIONS

SAMPLE: A VALUE ENGINEERING COSTING

• Public vs. Invited Bidders • Qualifications:

o RCABC members vs. non-members. o RCABC membership mandates TQ roofers,

bonds companies, and monitors contractor’s proficiency.

o TQ Roofer for flat roofs and sloped roofs • How a consultant can save you money:

o Spring roof project starts save money with lower pricing (10 -> 20%)

o Winter tendering saves money (save 10 -> 20%) o Flexible construction schedules may save money o Detailed designs reduce change orders (save 5 - 10%) o Managing claims and weeding out bogus claims (save) o Extended warranties with effective resolution clauses o Summer work restriction for July & August add cost (add 10 -> 25%)

TENDERING

• Roofing QAO is more in depth than a standard Field Review by an Architect or Engineer.

• Performed by a Registered Roof Observer (or equivalent).

• Roofing applicator experience of the Observer is very important.

• Verify materials delivered. • Review details prior to construction. • Review mock-ups. • Interim reviews are often daily. • Final review / acceptance. Milestone warranty reviews are typically scheduled in advance to help

ensure roof performance. o RCABC milestones at 2, 5, 8 years. o Owner scheduled reviews typically 1-3 year intervals.

QUALITY ASSURANCE OBSERVATIONS

(FIELD REVIEWS)


PHOTOGRAPHS

GUARDRAILS FOR CONSTRUCTION

ROOF DEMOLITION VAPOUR BARRIER /

TEMP ROOF

TORCHING PROCESS STARTING DEMO OF NEXT

SECTION CURB DETAIL QUESTION

FROM ROOFER


PHOTOGRAPHS

CURB INSTALLED ON TOP OF OLD ROOF

BOXED IN CURB SOLUTION OLD ROOF STILL BELOW

HVAC UNIT

SKYLIGHT TO METAL ROOF CONVERSION HERE

SNOW SHEDDING SOLUTION

SKYLIGHT PROTECTION


PHOTOGRAPHS

SNOW SHED CONVERTED TO ROOF

EXPANDING FOAM ADHESIVE

POLYISO BASE LAYER

METAL ROOF REPLACEMENT

METAL ROOF TO UNDERLAYMENT

NEW HVAC UNITS LANDED


PHOTOGRAPHS

MINERAL WOOL TOP LAYER

TORCH ON BASE AND CAP SHEETS

PARAPET FLASHINGS

FACE OF FLASHINGS BUILT IN GUTTER DETAIL METAL INSTALL


PHOTOGRAPHS

SKYLIGHT INSTALL WITH MEMBRANE TIE-INS

STRUCTURE NOT FLAT, RESOLVED WITH “SHIMMING” INSULATION

LAYER

PENETRATION FLASHINGS DETAIL

• Roofing Contractor o 1 or 2 year labour and material. o Extended labour warranty from some larger contractors. o Extended material warranties via Roofing Contractor is sometimes

offered; this is generally a flow through negotiated with the manufacturer.

• Manufacturer Warranties o Materials only warranty is standard. o Labour and materials warranty is offered.

• Trained / certified installers normally required. o 3rd party inspections often required. o Often many conditions designed to void the warranty. o Water tight remedy.

• They fill the hole, they don’t fix the root cause.

WARRANTIES

• RCABC RoofStar Guarantee o Note that QAO inspection costs are included. The cost is not all for

actuarial insurance cost. o They pay consultants to design and oversee the repair if applicable. A

claim is their headache, not yours. o They coordinate with insurance companies for the

owner and roofer if applicable. • Other 3rd Party Warranties, not common in BC • No Dollar Limit Warranties (NDL)

o Roofing costs increase over time. These warranties pay for the inflation value.

• Pro-rated Warranties o You only get a percentage of the roof value based on the years it was

in service. • Caution: Don’t buy a roof based on warranty. Do specify the right roof

system to suit your needs and then ensure that you obtain all warranties / guarantees that are applicable.

WARRANTIES

2013 Plan executed on time • Roofing, glazing, fall protection System:

o Torch on vapour barrier o Sloped polyiso base layer, adhered o Dual density mineral wool top layer, adhered o 2 ply composite re-inforced SBS modified

bitumen membrane, torch applied o 20 Year Manufacturer’s Warranty

2014 – Onwards: • New board of directors, lessons learned may

have been lost • 2014 phase is on hold • Library roof litigation unresolved

Recommendations to Owners: • Decision makers vary over time, and barring a formalized policy that

incorporate best practice roofing management, future decisions can be sub-optimal

• Owners should have a formal plan including assessments, budgeting, priorities, consulting, design requirements, QAO, warranties, etc.

FINAL OUTCOME – SCHOOL CASE STUDY

Brian Boomars, P.Eng. [email protected] www.ircgroup.com

Sustainable Roofing – Learning From Case Studies to Manage Your Roofing Investment”

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