understanding csa s478 guideline on durability in buildings part 5 understanding... ·...
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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
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
News: Bricks fall off Scarborough apartment
Saturday afternoon, April 4, 2015
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
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
Guideline on Durability in Buildings
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
Guideline on Durability in Buildings
or… ‘able to exist for a long time
without significant deterioration’?
Merriam-
Webster
Dictionary
Guideline on Durability in Buildings
Guideline on Durability in Buildings
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…
Guideline on Durability in Buildings
Guideline on Durability in Buildings
per OBC 5.1.4.2.(3), fulfilling this Guideline’s
requirements:
CSA S478-95
Guideline on Durability in Buildings
Structure (Design)
Reaffirmed in 2007 - CSA S478-95 (R2007)
Reaffirmed in 2001 - CSA S478-95 (R2001)
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.”
Guideline on Durability in Buildings
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)
Guideline on Durability in Buildings
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
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).
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
Conclusion 1
Inform the owner about the need for
maintenance.
• Prepare a Quality Assurance plan for
your services on the project.
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
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
Guideline on Durability in Buildings
Guideline on Durability in Buildings
App. F. The Building Envelope cont.
This cladding
must be cut off
to replace this
window and
rebuilt after.
Detail 11SI - Building
Enclosure Design Guide
Guideline on Durability in Buildings
App. F. The Building Envelope cont.
The window
trim can be
removed to
replace the
window and
can be
reinstalled.
Detail 11 EAB - Building
Enclosure Design Guide
Guideline on Durability in Buildings
App. F. The Building Envelope cont.
This wall base
trim can be
removed to
replace the
roofing and can
be reinstalled.
Detail 21 EAB - Building
Enclosure Design Guide
Why must Canadian architects be
registered?
To assure that their education, training
and experience meet the profession’s
standards.
Guideline on Durability in Buildings
Why must Canadian architects remain
registered?
To assure their competence and conduct
meet the profession’s standards.
Guideline on Durability in Buildings
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?
Guideline on Durability in Buildings
Assurance.
Society requires assurance of an architect’s
Competence - of technical judgments, and
Conduct – forthright advice and honest
service.
Guideline on Durability in Buildings
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
Guideline on Durability in Buildings
Attractive or beautiful?
“Arson is not really a
crime. There are many
buildings that deserve
to be burned down.”
H.G. Wells.
Guideline on Durability in Buildings
“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.
Guideline on Durability in Buildings
“I think Ms. (Marilyn)
Monroe as architecture
is extremely good
architecture.”
Frank Lloyd Wright
Guideline on Durability in Buildings
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
“I can’t define hard-core pornography …
but I know it when I see it.”
Associate Justice Potter Stewart in Jacobellis v.
Ohio, 1964.
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
Does a law require a building to be
attractive or beautiful?
No - and no law prohibits an average
looking or ugly building.
Guideline on Durability in Buildings
Does a law require a building to be
attractive or beautiful?
No.
Beauty is in
the eye of
the beholder.
Guideline on Durability in Buildings
“… if you have to keep the lavatory door
shut by extending your leg, it’s modern
architecture.”
Nancy B Smith
Guideline on Durability in Buildings
Guideline on Durability in Buildings
“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.”
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
And, do laws require a building to be
accessible, energy efficient and soon …
water efficient?
NBC 1970 NECB 2011 NPC 2015
Guideline on Durability in Buildings
Safe, accessible, etc.?
Yes, by complying with
applicable building
regulations and code
requirements.
Stele of Hammurabi
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
1750 BC – Hammurabi’s Code of 282 Laws
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.
Guideline on Durability in Buildings
1750 BC – Hammurabi’s Code of 282 Laws
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.
Guideline on Durability in Buildings
1750 BC – Hammurabi’s Code of 282 Laws
No. 232 – If a builder builds a house
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
Guideline on Durability in Buildings
1750 BC – Hammurabi’s Code of 282 Laws
No. 233 – If a builder builds a house
improperly and the walls seem toppling …
the builder must make the walls solid
from his own means.
Contract fulfillment
Guideline on Durability in Buildings
1750 BC – Hammurabi’s Code of 282 Laws
No. 228 - If a builder builds a house and
completes it,
.
(1 SAR= 36 sq m)
Guideline on Durability in Buildings
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.”
Guideline on Durability in Buildings
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
Guideline on Durability in Buildings
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
Guideline on Durability in Buildings
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.”
Guideline on Durability in Buildings
Guideline on Durability in Buildings
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;
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
BC’s code also requires an architect, as
the Coordinating Registered Professional ,
to:
• assign responsibility for all applicable
code requirements to professionals, and
Guideline on Durability in Buildings
• 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.
Guideline on Durability in Buildings
Standard architectural contracts require
the architect to review applicable building
codes and regulations in each design
phase:
• Schematic Design
• Design Development
• Construction Documents
Guideline on Durability in Buildings
Standard architectural contracts cont.
• and where necessary - review them with
the AHJs, and
• provide consultant coordination, and
Guideline on Durability in Buildings
Standard architectural contracts cont.
Guideline on Durability in Buildings
• 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?
Guideline on Durability in 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?
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
Does the OBC 2012 refer to
CSA S478-95
Guideline on Durability in BuildingsStructure (Design)
Reaffirmed in 2007 - CSA S478-95 (R2007)
Reaffirmed in 2001 - CSA S478-95 (R2001)
Published in 1995 - CSA S478-95
Guideline on Durability in Buildings
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)?
Guideline on Durability in Buildings
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?
Guideline on Durability in Buildings
Guideline on Durability in Buildings
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.
Guideline on Durability in 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
Guideline on Durability in Buildings
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
Guideline on Durability in Buildings
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
Guideline on Durability in Buildings
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.”
Guideline on Durability in Buildings
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
Guideline on Durability in Buildings
‘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.”
Guideline on Durability in Buildings
‘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’.
Guideline on Durability in Buildings
Guideline on Durability in Buildings
‘such as’ means
another similar standard such as:
‘ISO 15686: Building & Construction
Assets Service Life Planning.’
City of Toronto Green Roofs By-Law
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.
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
Foreword … to achieve durability:
2. Before design the designers must
account for the environmental loads and
deleterious agents that will affect
building components.
Guideline on Durability in Buildings
Foreword … to achieve durability:
3. During design procedures, the designers
must consider the life expectancy of the
building and its components.
Guideline on Durability in Buildings
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
2. Definitions
“Agent – whatever acts on a building or its
components that affects service life
(e.g., water, temperature).”
Guideline on Durability in Buildings
2. Definitions
“Assembly…more than one material or
component…
Examples… the total building envelope or
individual walls, roofs, or parapets.”
Guideline on Durability in Buildings
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…
Guideline on Durability in Buildings
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.”
2. Definitions cont.
“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.”
Guideline on Durability in Buildings
2. Definitions cont.
“Design Service Life - the service life
specified by the designer in accordance
with the expectations (or requirements) of
the owners of the building…
Guideline on Durability in Buildings
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.”
Guideline on Durability in Buildings
Guideline on Durability in Buildings
2. Definitions cont.
“Predicted Service Life - the service life
forecast from recorded performance,
previous experience, tests, or modelling.”
2. Definitions cont.
“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.”
Guideline on Durability in Buildings
Guideline on Durability in Buildings
2. Definitions cont.
“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,…
Guideline on Durability in Buildings
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.”
Guideline on Durability in Buildings
4.2 Basic Durability Requirement
Renovation
• The design service life of the revised
structure shall be reconsidered.
Guideline on Durability in Buildings
4.3 Basic Durability Requirement
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.
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
Guideline on Durability in Buildings
5. Quality Assurance
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.
Guideline on Durability in Buildings
5. Quality Assurance
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.
Guideline on Durability in Buildings
6. Design Service Life of Buildings and Components
Figure 8-1 35-year life cycle costs. Building Enclosure Design Guide
Guideline on Durability in Buildings
Building Enclosure Design Guide
6. Design Service Life of Buildings and Components
6. Design Service Life of Buildings and Components
6.1 Buildings and Components
Requirements for durability of a building
or component are expressed in terms of
design service life.
Guideline on Durability in Buildings
Guideline on Durability in Buildings
6. Design Service Life of Buildings and Components
6.2 Buildings
The designer determines the design
service life per the owner’s requirements.
Table 2.
Guideline on Durability in Buildings
6. Design Service Life of Buildings and Components
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
Guideline on Durability in Buildings
6. Design Service Life of Buildings and Components
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
Guideline on Durability in Buildings
6. Design Service Life of Buildings and Components
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.
Guideline on Durability in Buildings
6. Design Service Life of Buildings and Components
6.3.2. Difficulty & Cost of Maintenance
To extend a lifecycle, select a more
resistant component, or implement more
maintenance, or both.
Guideline on Durability in Buildings
6. Design Service Life of Buildings and Components
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.
Guideline on Durability in Buildings
6. Design Service Life of Buildings and Components
6.3.4. Component Selection
Also affected by:
• cost – availability, construction
knowledge
• aesthetics
• environmental impact.
Guideline on Durability in Buildings
6. Design Service Life of Buildings and Components
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.
Guideline on Durability in Buildings
6. Design Service Life of Buildings and 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
Guideline on Durability in Buildings
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. Predicted Service Life of Components & Assemblies
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.
Guideline on Durability in Buildings
Guideline on Durability in Buildings
7. Predicted Service Life of Components & Assemblies
7.2.3. Methods to Predict Service Life:
demonstrated effectiveness
applies where identical assemblies have
been used successfully and in the same
environments.
Guideline on Durability in Buildings
7. Predicted Service Life of Components & Assemblies
7.2.3. Methods to Predict Service Life:
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.
Guideline on Durability in Buildings
7. Predicted Service Life of Components & Assemblies
7.2.3. Methods to Predict Service Life:
testing & modeling
apply to innovative components, and
to proven components in significantly
different environments.
Guideline on Durability in Buildings
7. Predicted Service Life of Components & Assemblies
7.6. Building Science Principles & Modeling
7.6.1. Local Environments
Moisture is the most important
environmental agent causing premature
deterioration.
Guideline on Durability in Buildings
7. Predicted Service Life of Components & Assemblies
7.6. Building Science Principles & Modeling
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.
Guideline on Durability in Buildings
7. Predicted Service Life of Components & Assemblies
7.6. Building Science Principles & Modeling
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.
Guideline on Durability in Buildings
7. Predicted Service Life of Components & Assemblies
7.6. Building Science Principles & Modeling
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.
Guideline on Durability in Buildings
7. Predicted Service Life of Components & Assemblies
7.6. Building Science Principles & Modeling
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.
Guideline on Durability in Buildings
Guideline on Durability in Buildings
8. Design Considerations
8.3 Materials Selection
Materials should have:
• physical & chemical compatibility
• proper physical & chemical properties
• proper differential movement properties
Guideline on Durability in Buildings
8. Design Considerations
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.
Guideline on Durability in Buildings
8. Design Considerations
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.
Guideline on Durability in Buildings
8. Design Considerations
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.
Guideline on Durability in Buildings
8. Design Considerations
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.
Guideline on Durability in Buildings
8. Design Considerations
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.
Guideline on Durability in Buildings
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
10. Operation, Maintenance & Inspection
Recommended to owner: Prepare a
maintenance & inspection program &
budget during construction documents.
Update these for construction changes.
Retain a copy of all construction
documents.
Guideline on Durability in Buildings
10. Operation, Maintenance & Inspection
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
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
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
Guideline on Durability in Buildings
Guideline on Durability in Buildings
Figure C2:
Weighted Mean pH of
Precipitation for North America
for the Period 1976-1979
Guideline on Durability in Buildings
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.’
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
Guideline on Durability in Buildings
Conclusion 1
Inform the owner about the need for
maintenance.
• Prepare a Quality Assurance plan for
your services on the project.
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
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.
Guideline on Durability in Buildings
Thank you!
Part 5 Understanding DurabilityOntario OBC 2006 & 2012
Toronto Green Roof Bylaw
Vancouver Building Bylaw