Understanding CSA S478 Guideline on Durability in Buildings Part 5 Understanding... · Understanding CSA S478 Guideline on Durability in Buildings Toronto –May 11, 2016. ... 1750

OBC Part 5: What is a Durable Building?Understanding CSA S478�

Guideline on Durability in Buildings

Toronto – May 11, 2016

OBC Part 5: What is a Durable Building?Ontario OBC 2006 & 2012

Toronto Green Roof Bylaw

Vancouver Building Bylaw


OBC Part 5: What is a Durable Building?

John Hackett

Architect OAA, FRAIC, Vice President, Practice Risk

Management, ProDemnity Insurance Company, Toronto

Brian Sim

Architect AIBC, PP/FRAIC, Hon. FAIA, Hon. FCARM.

Brian Sim Architect, West Vancouver, BC

Dave KayllP. Eng., FMA, Principal, Building Science Specialist,

Morrison Hershfield, Ottawa.


News: Six occupants die, seven injured.

Six students fell to

their death when a

4th floor balcony

collapsed in Berkeley

on June 16, 2015.

Seven others were

injured.


News: Why?

Joists rotted by water

ingress or condensation

are being analyzed in

separate criminal and

civil investigations. The

building was built in

2006-07 and reportedly

was poorly maintained.


News: Bricks fall off Scarborough apartment

Saturday afternoon, April 4, 2015


News: Bricks fall off Scarborough apartment“The brick veneer has had some water penetration and

freeze thaw… popped the bricks and had a bit of a

cascade… THC buildings are regularly inspected for

these types of issues…With old buildings, you just

can’t predict when this kind of thing is going to

occur.”

TCHC CEO Greg Spearn told Codi Wilson

of CP24.com, April 4, 2015.


Recent News: Roof Collapse Kills Two Report of the Elliot Lake Commission of Inquiry, 2014

“Although it was rust that defeated the structure…

the real story behind the collapse is one of human,

not material , failures”. Commissioner Belanger


Recent News: Roof Collapse Kills Two

Algoma Centre Mall, Elliot Lake, 2 pm - June 23, 2012

August 5, 1980 – Substantial Completion Declared

39’ x 79’ of roof fell after 30 roof leak reports in 33 years.

‘what does ‘durable’ mean - ‘hard wearing’?

Oxford

Concise

English

Dictionary


or… ‘able to exist for a long time

without significant deterioration’?

Merriam-

Webster

Dictionary



What is ‘durability’ and does the OBC

require ‘durability’ of a building’s envelope?

Durability is a function of a material in its

environment and in Ontario it means…

means…



per OBC 5.1.4.2.(3), fulfilling this Guideline’s

requirements:

CSA S478-95


Structure (Design)

Reaffirmed in 2007 - CSA S478-95 (R2007)


Published in 1995 - CSA S478-95

Durability Guideline definition:

“Durability - the ability of a building or

any of its components to perform its

required functions in its service

environment over a period of time

without unforeseen cost for

maintenance or repair.”


1 day Design Service Life 1,207 year Service Life to date

1 day Predicted Service Life since 708 AD

1 day Service Life (actual life)



Good news for architects

The Durability Guideline is only 17 pages

…but the Appendices are 76 pages.

Good news for clients

Complying with the Guideline does not

necessarily increase construction costs.


Sad news for clients

To account for the work of complying with

OBC 5.1.4.2.(3) an architect’s basic fee (%,

hourly or fixed) should be increased

because code compliance is a Basic Service,

in standard architectural contracts (not an

Optional or Additional Service).


Architect’s Compliance: DIY or with a BEC?

Will you ‘Do It Yourself’ or work with a Building

Envelope Consultant?

Either way - integrate your durability

services with your new, code-required,

‘Energy Efficiency’ envelope services.


Conclusion 1

Inform the owner about the need for

maintenance.

• Prepare a Quality Assurance plan for

your services on the project.


Conclusion 2

Discuss the owner’s required Design

Service Life for the building envelope

components and assemblies.

• Prepare and confirm with the owner

the construction costs estimates and

maintenance life cycle cost estimates.


Conclusion 3

Specify and confirm with the owner the Predicted Service Life of the building envelope components and assemblies.

• Apply the principles of building

science - documented demonstrated effectiveness, modeling and tests.


Conclusion 4

Provide the owner with a copy of all

design, construction, and maintenance

documents for the building and its

envelope components and assemblies.

• And, retain your records.

App. F. The Building Envelope

• The building envelope is the costliest

part of a building and the costliest part

to repair.

• Envelope failures are usually due to

moisture in walls or roofs.


App. F. The Building Envelope cont.

• Joint design and construction are the most

difficult tasks.

• Replacing deteriorated components is aided by

‘durability-designed’ junctions, e.g.,

�wall penetrations, e.g., window flanges or frames

behind wall cladding

�roofing & decking upturns under wall cladding




This cladding

must be cut off

to replace this

window and

rebuilt after.

Detail 11SI - Building

Enclosure Design Guide



The window

trim can be

removed to

replace the

window and

can be

reinstalled.

Detail 11 EAB - Building




This wall base

trim can be

removed to

replace the

roofing and can

be reinstalled.

Detail 21 EAB - Building


Why must Canadian architects be

registered?

To assure that their education, training

and experience meet the profession’s

standards.


Why must Canadian architects remain

registered?

To assure their competence and conduct

meet the profession’s standards.


Most Canadian provinces grant architects

exclusive rights to:

Title - ‘architect’ - and

Practice - to design and review the

construction of large buildings.

What does society require of architects?


Assurance.

Society requires assurance of an architect’s

Competence - of technical judgments, and

Conduct – forthright advice and honest

service.


Does society, like Vitruvius in 50 BC,

require assurance that a building has

these 3 qualities?

Utilitas - commodity – useful,

Firmitas - firmness – safe, and

Venustas - delight – beautiful


Does a law require a building to be

attractive or beautiful?


Attractive or beautiful?

“Arson is not really a

crime. There are many

buildings that deserve

to be burned down.”

H.G. Wells.


“You have to give this much to the

Luftwaffe – when it knocked down our

buildings it did not replace them with

anything more offensive than rubble. We

did that.”

Prince Charles.


“I think Ms. (Marilyn)

Monroe as architecture

is extremely good

architecture.”

Frank Lloyd Wright



An architect gets a program, budget, place,

schedule: “Sometimes the end product rises to

art - or at least people call it that.”- Frank Gehry

“I don’t know anything about art, but I

know what I like.”

Gellet Burgess

1866 – 1951.


“I can’t define hard-core pornography …

but I know it when I see it.”

Associate Justice Potter Stewart in Jacobellis v.

Ohio, 1964.


Attractive or beautiful?

Zoning bylaws about a building’s uses, size, character, etc., make neighborhoods ‘livable’ by making buildings compatible – not necessarily attractive.

Design Panel ‘recommendations’ to change a building’s appearance are negotiable - not requirements.




No - and no law prohibits an average

looking or ugly building.




No.

Beauty is in

the eye of

the beholder.



useful?


“… if you have to keep the lavatory door

shut by extending your leg, it’s modern

architecture.”

Nancy B Smith


Useful?



“Architecture is the art of how to waste

space.” Philip Johnson.

Wright’s reply to a client who complained

the roof leaked water onto the dining table…

“Move the chair.”


Useful ?

An architect’s contract to design a

building that serves the client’s

requirements is enforceable by law.

But no law requires an owner to request

or have an efficient or useful building.


Useful?

No law prohibits an inefficient or useless

building.


Does a law require a building to be safe

from … collapse?


… falls?


… fire?


… water-borne diseases?


Do laws require a building to be safe?


And, do laws require a building to be

accessible, energy efficient and soon …

water efficient?

NBC 1970 NECB 2011 NPC 2015


Safe, accessible, etc.?

Yes, by complying with

applicable building

regulations and code

requirements.

Stele of Hammurabi


1750 BC – Hammurabi’s Code of 282 Laws

No. 229 - If a builder builds a house

improperly and it falls and kills the owner

– the builder shall be put to death.

Retribution and deterrence. No restitution.



No. 230 – If a builder builds a house

improperly and it falls and kills the

owner’s son - the builder’s son shall be

put to death.

Retribution and deterrence. No restitution.



No. 231 - If a builder builds a house

improperly and it falls and kills the

owner’s slave – the builder shall pay slave

for slave.

Deterrence and restitution. No retribution.




improperly and it ruins goods therein,

the builder shall make full compensation

and if the house falls, the builder shall

re-erect it from his own means.

Restitution and contract fulfillment




improperly and the walls seem toppling …

the builder must make the walls solid

from his own means.

Contract fulfillment



No. 228 - If a builder builds a house and

completes it,

.

(1 SAR= 36 sq m)


620 BC – Deuteronomy 22:8, Moses said

“When thou buildest a new house, then thou

shall make a battlement for thy roof – that thou

bring not blood upon thy house

- if any man fall from thence.”


Western Building Codes

1189 London’s ‘Assize of Buildings’

1212 London fire led to ban on thatched roofs

1666 London’s Great Fire led to ‘Building Act’:

brick buildings, wider streets, storey limit

1858 England’s ‘Local Government Act’

1930 USA codes ‘save people - not buildings’

1941 Canada’s National Building Code


Canada’s Codes

1941 National Building Code = safety + health

1963 National Fire Code

1970 NBC adds accessibility

1970 National Plumbing Code

1997 Model National Energy Code

2011 National Energy Code for Buildings

2015 NPC will add water efficiency


Ontario Building Code Act, 1992

“Role of various persons 1.1.(1)

It is the role of every person who causes

a building to be constructed, (a) to cause the

building to be constructed in accordance with

this Act and the building code and with any

permit issued under this Act for the building.”



Ontario Building Code Act, 1992

“Role of designers 1.1.(2)

It is the role of the designer … to provide

designs which are in accordance with this

Act and the building code and to provide

documentation that is sufficiently detailed

to be assessed for compliance with this Act

and the building code…”

Modern building codes and/or

professional bylaws require that:

• architects design large buildings and some small buildings, and the

• architects’ designs shall comply with applicable codes;


Modern building codes and/or

professional bylaws cont.

• architects shall review construction for

compliance with the design and

applicable codes, and

• architects shall assure they reviewed the codes and the construction.


BC’s code also requires an architect, as

the Coordinating Registered Professional ,

to:

• assign responsibility for all applicable

code requirements to professionals, and


• coordinate the professionals’ designs,

field reviews and shop drawing reviews,

and

• coordinate tests of fire protection and

life safety systems to ascertain

substantial compliance in all material

respects with BCBC requirements.


Standard architectural contracts require

the architect to review applicable building

codes and regulations in each design

phase:

• Schematic Design

• Design Development

• Construction Documents


Standard architectural contracts cont.

• and where necessary - review them with

the AHJs, and

• provide consultant coordination, and


Standard architectural contracts cont.


• conduct Field Review/General Review

of the Work for its quality and general

conformity with the construction

contract documents and so report, in

writing, to the client, contractor and

the Chief Building Official.

Does the OBC 2012 apply to

the design, construction and occupancy

of all new buildings and …the alteration,

reconstruction, relocation and occupancy

of all existing buildings?


Does a building’s envelope include

�roofs & decks

�exterior walls & projections

�interior walls & floors between different

environments

�foundation walls, lowest floor/slab,

�foundation drainage & backfill?


Does the NBC require a building’s

envelope to be durable?

No - the NBC does not

refer to ‘durable’ or

‘durability’. They are not

in the NBC Index.


Does the OBC 2012 refer to

CSA S478-95

Guideline on Durability in BuildingsStructure (Design)



Published in 1995 - CSA S478-95


Was the Durability Guideline required by

• Ontario Building Code 2006,

• Brit. Col. Building Code 1998,

• Vancouver Building By-Law 1996,

• Vancouver Development Permits, and

• LEED Canada Version 1.0 Dec. 2004:

Materials & Resources Credit 8 (optional)?


Is the Guideline required by the

• Ontario Building Code 2012 at

5.1.4.2.(3) Resistance to Deterioration,

• Toronto Green Roofs Bylaw, and

• Vancouver Building By-Law 2013

• LEED Canada NC 2009 optional Regional

Priority Credit for durability?



Do Part 5 requirements apply to

all Part 3 buildings, i.e., to all buildings

except Part 9 buildings that comply with

Part 9 envelope requirements?

OBC 5.1.4.2.(3) applies to

the design, construction and occupancy

of all new buildings and …

the alteration, reconstruction, relocation

and occupancy of all existing buildings.


2012 and 2006 OBC 5.1.4.2.(1)

Resistance to Deterioration (See Appendix A)

(1) …materials used in building components and

assemblies that have separate dissimilar

environments, or in assemblies exposed to the

exterior, shall be ,

(a) compatible with adjoining materials, and


2012 and 2006 OBC 5.1.4.2.(1) cont.

(b) resistant to any mechanisms of deterioration that may reasonably be expected given,

(i) the nature and function of the materials,

(ii) the exposure of the materials, and

(iii) the climatic conditions in which the

materials will be installed. NEW in 2012


2012 and 2006 OBC 5.1.4.2.(2)

(2) Material compatibility and deterioration

resistance are not required where it can be

shown that incompatibility or uncontrolled

deterioration will not adversely affect any of,

a) the health of safety of building users,

b) the intended use of the building, or

c) the operation of building services


2012 and 2006 OBC 5.1.4.2.(3)

(3) Design and construction of assemblies

separating dissimilar environments and

assemblies exposed to the exterior shall be in

accordance with good practice such as

described in CSA S478, “Guideline on

Durability in Buildings.”



‘assembly’ means “more than one material

or component…Examples are the total

building envelope or individual walls, roofs,

or parapets.

CSA S478


‘in accordance with’ means

“in a manner conforming with”

Oxford Concise English Dictionary

‘good practice’ was defined in NBC 1960

in ‘Part 9 Housing’ for 1 or more dwelling

units, max. 2 storeys as

“…where ‘good practice’ is used…the

appropriate provisions of the Canadian

Housing Standards…by NRC…shall be used as a

guide by the authority having jurisdiction to

satisfy the requirement.”


‘good practice’ meant:

The building official agrees that a practice,

such as a design detail, is based on an

applicable detail in the ‘Canadian Housing

Standards.’ i.e., a reputable published standard.

‘good practice’ means:

‘What a prudent architect does – designs in

accord with CSA S478 Guideline on Durability’.



‘such as’ means

another similar standard such as:

‘ISO 15686: Building & Construction

Assets Service Life Planning.’

City of Toronto Green Roofs By-Law

Bylaw 583-2009



IV Construction Standard - N. Maintenance Plan

(1) The applicant shall develop a maintenance

plan for the green roof as per CSA-S478-95

“Guideline on Durability in Buildings”… to

ensure that the green roof components

perform their required functions for… their

design service lives.




Durability Guideline Foreword: 3 explicit

assumptions to achieve durability:

1. All decisions during the life of a building,

even decisions before design, affect all

subsequent decisions and the resultant

performance of the building.


Foreword … to achieve durability:

2. Before design the designers must

account for the environmental loads and

deleterious agents that will affect

building components.


Foreword … to achieve durability:

3. During design procedures, the designers

must consider the life expectancy of the

building and its components.



1. Scope

1.1 advice about including requirements

for durability into the design, etc.

1.2 guidance on achieving durability by

planning the design, construction, etc.

1.3 excludes mechanical and electrical

systems – but includes their impacts.


2. Definitions

“Agent – whatever acts on a building or its

components that affects service life

(e.g., water, temperature).”


2. Definitions

“Assembly…more than one material or

component…

Examples… the total building envelope or

individual walls, roofs, or parapets.”


2. Definitions cont.

“Building science – in the design of

buildings and their assemblies, the study

and application of principles governing

physical, chemical, and electro-chemical

behavior…


Building science cont.

in order to predict effects on an assembly

due to loads placed on the materials and

components on and within the assembly,

and their impact over time.”


“Durability - the ability of a building or

any of its components to perform its

required functions in its service

environment over a period of time

without unforeseen cost for

maintenance or repair.”



“Design Service Life - the service life

specified by the designer in accordance

with the expectations (or requirements) of

the owners of the building…


Design Service Life cont.

for given materials…exposed to identical

loads, the design service lives for similar

buildings are adjusted depending on the

amount and nature of maintenance the

owners commit to carry out during the

lives of the completed buildings.”




“Predicted Service Life - the service life

forecast from recorded performance,

previous experience, tests, or modelling.”


“Service Life - the actual period of time

during which the building or any of its

components performs without

unforeseen costs or disruption for

maintenance and repair.”




“Premature failure – failure occurring prior

to achievement of the design service life.”

4.1 Basic Durability Requirement

“Buildings and their components shall be

conceived , designed, constructed, and

operated and maintained in such a way

that, under foreseeable environmental

conditions, they maintain their required

performance during their design service

lives.” And,…


4.1 Basic Durability Requirement cont.

“The predicted service life of buildings and

building components and assemblies

should meet or exceed their design service

life.”



Renovation

• The design service life of the revised

structure shall be reconsidered.



Repair

• Repairs shall be designed, constructed

and maintained to provide the required

performance over the design service life

as agreed by the owner and designer.


5. Quality Assurance

5.1 Durability, QA and Life Cycle

To achieve durability, quality assurance

is essential at every stage in the life of

the building. Table 1.




5.2.1. Elements of QA

Durability can be achieved only with the

required quality of design, materials,

workmanship … and maintenance …

5.2.2.- 4. Quality assurance is essential.

The quality management program ISO

Standard 9001 is recommended.



5.3.1.-2. Elements of Quality Management

In design, prepare a maintenance plan

for monitoring, repairs and replacements

of components to assist in defining

objectives. Appendix A – maintenance data

sheets.



6. Design Service Life of Buildings and Components



Figure 8-1 35-year life cycle costs. Building Enclosure Design Guide


Building Enclosure Design Guide



6.1 Buildings and Components

Requirements for durability of a building

or component are expressed in terms of

design service life.




6.2 Buildings

The designer determines the design

service life per the owner’s requirements.

Table 2.




6.3.1. Determine Component DSL

The designer determines the design service

life of each component based on:

• exposure conditions – Appendix C

• difficulty & expense of maintenance

• consequences of failure – Table 3



6.3.1. Determine Component DSL cont.

• future availability of suitable components

• the design service life of the building –

Appendix A

• technical or functional obsolescence




6.3.2. Difficulty & Cost of Maintenance

For each component: determine its

design service life by categorizing it’s

maintenance as ‘little/none’ or ‘significant’

or ‘extensive’ based on the cost, difficulty,

extent and frequency of maintenance.



6.3.2. Difficulty & Cost of Maintenance

To extend a lifecycle, select a more

resistant component, or implement more

maintenance, or both.



6.3.3. Consequences of Failure

Design, as most reliable, the components

whose failure will imperil life or health.

If a detail is critical to durability: consider

designing redundant protection.



6.3.4. Component Selection

Also affected by:

• cost – availability, construction

knowledge

• aesthetics

• environmental impact.



6.3.5. Service Life: Component v. Building

Permanent components to have the same

service life as the building.

Above grade: design more resistant

components behind less resistant

components.



6.4. Specify the Design Service Life

DSL statement & info by designer & owner re:

a) building, components & assemblies

b) exposure, environment & use

c) maintenance: Clause 10

d) design exposure conditions: Clauses 7 & 8


7. Predicted Service Life of Components & Assemblies

7.1–2.1. Methods to Predict Service Life

The PSL of a component is approximated

based on one or more methods:

• demonstrated effectiveness: Clause 7.3

• modeling (of deterioration): Clause 7.4

• testing: Clause 7.5


7.2.2. Methods to Predict Service Life

Any method used to predict PSL should be

based on a sound understanding and

application of building science principles:

Clause 7.6.




7.2.3. Methods to Predict Service Life:

demonstrated effectiveness

applies where identical assemblies have

been used successfully and in the same

environments.




modeling & demonstrated effectiveness:

apply to a similar component successfully

used in the same environment, or to a

proven component used successfully in a

moderately different environment.




testing & modeling

apply to innovative components, and

to proven components in significantly

different environments.



7.6. Building Science Principles & Modeling

7.6.1. Local Environments

Moisture is the most important

environmental agent causing premature

deterioration.




7.6.1. Local Environments

Applying principles of building science enables

modeling of the mechanisms, paths, volumes,

and forms of moisture that assemblies need to

accommodate and resist.




7.6.2. Movement

Movement of adjacent components is due to

dimensional changes caused by material

characteristics, temperature, moisture in

materials and atmosphere, and stresses due to

services loads.




7.6.3. Deterioration & Damage Mechanisms

Caused by expected environmental conditions,

chemical & physical properties of materials, and

the chemical (galvanic corrosion) and physical

(movements, deformations) interactions of

components. Corrosion: often unforeseen & costly.




7.6.4. Failure

Defined by effects of deterioration on a

component’s appearance or function: a limit

state exceeded = functional failure, e.g., excess

movements, weakening, fracture or gap.

Appendices D & F.

8. Design Considerations

8.2 Convention & Innovation

Designs should be based on published

‘Standards’ and proven design & construction

practices whenever possible.

Innovative technology should be based on

sufficient modeling and/or testing.




8.3 Materials Selection

Materials should have:

• physical & chemical compatibility

• proper physical & chemical properties

• proper differential movement properties



8.4 Detailing “God is in the Details. Go with God.”

To be clear, concise in completed drawings

& specs. Minimize moisture infiltration,

deposition & accumulation via barriers &

seals, drainage & vents and the location &

forms of components. Minimize exposure.



8.5 Ease of Construction

Documents should include: input from the

building’s operator & builders; realistic

levels of workmanship, the allowable and

expected construction tolerances.



8.6 Operation & Maintenance

Designs for buildings, components &

assemblies (and M&E) should include easy

access for inspections, monitoring, tests,

maintenance, repair and replacement

throughout their service lives.



8.7 Functional Obsolescence

Design of a building expected to change its

use during its service life should allow for

future alterations of its spaces & systems

and re-use or recycling of its components.



8.8 Life Cycle Cost

All decisions about materials selection,

detailing, buildability and operation and

maintenance should account for all first

costs and all life cycle costs.

9. Construction Considerations

Trade briefings and mock-ups are

recommended for innovative materials,

products and designs.



10. Operation, Maintenance & Inspection

An owner’s regular maintenance &

inspections of the building’s materials,

components & assemblies are necessary

for their functional & aesthetic

performance throughout their design

service lives.



Recommended to owner: Prepare a

maintenance & inspection program &

budget during construction documents.

Update these for construction changes.

Retain a copy of all construction

documents.



An owner should obtain:

• shop drawings & as-built drawings

• operating manuals & training information

• Comprehensive Design Life & Maintenance Summary Table (App. A)

• schedules, budgets & record forms for all maintenance & inspections, in detail.

11. Investigation of Deterioration

12. Repair Work

13. Renovation


App. A. How to use the Guideline

Building codes do not set the DSL or PSL or the

service lives of buildings.

• owner sets the DSL with designer input

• designer sets the PSLs with owner’s OK

• designer’s documents are the bases of the owner’s program for maintenance during the building’s service life.





App. B. Costs of Premature Deterioration

1989: $50 mil in claims for failed facades in

Canada. Ontario New Home Warranty

paid $29 mil in 2 years.

1985-2005: $4 bil for BC ‘Leaky Condos’

and 40 % remain unrepaired.


App. C. Assessment of Environmental

Conditions

• water, air, & soil contaminants,

• sulphur dioxide, nitric acid, chlorides

• organisms, temperature, solar radiation

• micro & macro environments

• exposure periods & severity





Figure C2:

Weighted Mean pH of

Precipitation for North America

for the Period 1976-1979


Figure C3 (Part 1)


Figure C3 (Part 2)


Figure C3 (Part 3)


Figure C3 (Part 4)


Figure C4:

Decay Hazard Map of North America

(For Wood in Above Ground

Exposed Application)


App. D. Deterioration Mechanisms for

Building Materials

See ‘Table D1 Deterioration Mechanisms

for Building Materials and Their Control.’



App. E. The Corrosion of Metals in Building

Environments

• Metal corrosion is the costliest

unforeseen problem in buildings.

• It is the problem least addressed by

building codes and standards.






Conclusion 1

Inform the owner about the need for

maintenance.

• Prepare a Quality Assurance plan for

your services on the project.


Conclusion 2

Discuss the owner’s required Design

Service Life for the building envelope

components and assemblies.

• Prepare and confirm with the owner

the construction costs estimates and

maintenance life cycle cost estimates.


Conclusion 3

Specify and confirm with the owner the Predicted Service Life of the building envelope components and assemblies.

• Apply the principles of building

science - documented demonstrated effectiveness, modeling and tests.


Conclusion 4

Provide the owner with a copy of all

design, construction, and maintenance

documents for the building and its

envelope components and assemblies.

• And, retain your records.


Client Maintenance Acknowledgement

A brief letter for architects to give to

clients/owners wherein the client/owner

acknowledges responsibility for maintaining

the building envelope after construction is

being considered. Please stay tuned.


Thank you!

Part 5 Understanding DurabilityOntario OBC 2006 & 2012



Part 5 Understanding DurabilityOntario OBC 2006 & 2012

