For designers to build in resilience and adaptability to meet future climate loads, Building Codes must evolve to include predictive temperature, precipitation, wind, gust, and other environmental loads on buildings. This slide show includes selected information from ECCC on explains the current serious limitations facing designers.

1. Climate Change and Building
Codes
Gerald R. (Jerry) Genge
P.Eng., C.Eng., BDS, BSSO, C.Arb., Q.Med.
OBEC Monthly Meeting January 17, 2018

2. As written in a 1897 editorial in
the Hartford (Connecticut) Courant…largely and
incorrectly credited to Mark Twain, Charles Dudley
Warner is quoted as saying:
“A well known American writer said once that, while
everybody talked about the weather, nobody seemed
to do anything about it.”
Apparently, we can not say that any longer…..

3. In Case you haven’t heard…
Climate Change is a reality and there is data to
show that human influence has created the
differences.
Other regulations are attempting to mitigate causes of
Climate Change….
“Green Energy” Act, etc. but…
Unfortunately, today’s codes and standards do NOT
address design to accommodate Climate Change.

5. The Canadian Government has
heard …
May 2016 Office of Auditor General report noted that:
“the National Building Code administered by the National
Research Council of Canada did not incorporate climate change
trends.”
“although the Commission used some climate load values in
developing the 2015 Code – such as snow load values – the current
approach to building design is based solely on historic data and
does not take into account climate change trends.”
NRCC agreed and is coordinating with Environment and Climate
Change Canada and Canadian Standards Association

6. Durability has had some traction…
OBC Part 5 has referenced CSA S478 “Guideline
for Durability in Buildings”…. but
The CSA Guideline, written in 1995 was focused
on building durability without considering
Climate Change as a “load”.
It is now being updated to include Climate
Change as a “load”.

7. Loads on a Building
Physical Loads (effects of rain, wind, snow, and
temperature on structural sufficiency at time of
design and construction - per Part 4 including
load factors)
Environmental Loads (effects of rain, wind,
snow, and temperature on building envelope
performance at the time of design and
construction – no load factors in OBC –
performance based on testing)

8. Resistance to Loads
Physical Loads… Design to Part 4/Part 9
Environmental Loads… Design to Part 5/Part 9
Deterioration … Effects of physical and
environmental loads over time – no criteria, no
load factors – no mandated standard – just the
CSA S478 Guideline (which is largely ignored )
Conceptually, what is the issue?

9. Resistance to Deterioration
Designed Resistance
of a population of
buildings
Parameter
Frequency

10. Resistance to Deterioration
Loads on a
population of
buildings
Designed Resistance
of a population of
buildings
Parameter
Frequency

11. Resistance to Deterioration
Loads on a
population of
buildings
Designed Resistance
of a population of
buildings
Failure
Parameter
Frequency

12. Effect of Deterioration
Loads on a
population of
buildings
Decaying Resistance
of a population of
buildings
Parameter
Frequency

13. Effect of Deterioration
Loads on a
population of
buildings
Decaying Resistance
of a population of
buildings
Failure
Parameter
Frequency

14. Introduce Climate Change
Now the Loads are not considered to be
constant
Physical
Environmental, and
Deterioration
All are expected to change…

15. Effect of Climate Change
Loads on a
population of
buildings
Decaying Resistance
of a population of
buildings
Parameter
Frequency

16. Effect of Climate Change
Loads on a
population of
buildings
Decaying Resistance
of a population of
buildings
Parameter
Frequency
Some CC
Loads
may
decrease

17. Effect of Climate Change
Loads on a
population of
buildings
Decaying Resistance
of a population of
buildings
Parameter
Frequency
Failure
Some CC
Loads
may
decrease

18. Effect of Climate Change
Loads on a
population of
buildings
Decaying Resistance
of a population of
buildings
Parameter
Frequency
Failure
Some CC
Loads
may
decrease

19. Current State of Design…
Design criteria for Part 5 has always taken a
“rear view mirror” approach.
Climate Loads in NBC/OBC are derived for 50-
year historical data (now being updated but still
looking backward)
To accommodate or adapt to CC, building design
requires predictive data (Now being considered
as a mandate of the NBC)

20. Climate Change is the motivation
for…
Transformation from a CSA S478 Guideline into a
Standard
Incorporation of Climate Change Loads affecting
Durability into future building codes… but
Mandatory requirments will likely not become
mandatory until 2025
If we know….Why so slow?
We don’t know as much as we would like to know.

21. Environment and Climate Change
Canada Studies
(FormerlyEnvironmentCanada)…
ECCC has worked with other similar bodies globally to
create predictive models
… and has searched (for example) temperature records
as a foundation for promoting Climate Change research
e.g. CO2 and methane (GHG) trapped in ice cores
Here’s taste of what has been found…

23. Climate Change Parameters
(for Building Envelope Design)
Temperature

26. RPC: Representative
Concentration
Pathway”
Gigatonnes of CO2 production per year to achieve
Paris Accord 2 deg C target by 2100

27. RPC: Representative
Concentration
Pathway”

29. RPC: Representative
Concentration
Pathway”

31. Climate Change Parameters
(for Building Envelope Design)
Temperature

32. Temperature
What we believe so far:
Research
Canada… 1950 to 2010 ↑ 1.5 C°
Twice that of global average
More prevalent in north and west
Predictions
to 2100 temp ↑ a further 1.5 to 2.5 Cᵒ in summer
to 2100 temp ↑ a further 3 to 7 C in winter
Potentially ↑ a further 9 Cᵒ in Hudson’s Bay and arctic for reduced sea
ice
1:20 year events will become 1:5 year events
Effects
↑ length, frequency and intensity of extremes (e.g. heat waves)
↑ more unusually warm days and nights
↓ fewer cooler days and nights

33. CC Parameters (Cont’d)
Temperature
Precipitation

34. If we allow GHG to increase at
the highest predictive model
level:
• Over the next 20 to 50 years,
precipitation in coastal and
near coastal regions will
increase by 20 to 40%
• Over 50 to 80 years it will
increase by 60+%
[relative to 1986 – 2005]

35. Precipitation
Research
1950 to 2010 ↑ 16% …Mostly in Coastal Canada
Mostly in Spring and Fall
↓ in winter in Western Canada .. But due to decreased snowfall rather
than decreased rainfall
Predictions (CC models not as good as those for Temp)
Predictions are more variable but ↑ in all areas except Southern Canada
Except for Southern Canada most indicate shifts in wet and dry
extremes
1:20 events to be 1:10 by 2050 and increasing in frequency to 2100
Effects
↑ flooding and also ↑ droughts
↑ moisture load on buildings
Uncertain effects from more severe regional weather events

36. 2. CC Parameters
(for Building Envelope Design)
Temperature
Precipitation
Snow

37. Snow
Research
Western Canada: decreased winter precipitation (snowfall) rather than
a decrease in rainfall
Average annual snowfall across Canada has decreased by about 4%,
North and Atlantic regions have seen increasing trends in snowfall but
are extreme events not gradual accumulations of snow.
In recent years, rain on snow events have increased along with the
density of the snowpack.
Predictions (CC models not reliable as yet)
Snow season length and snow depths will likely decrease over most of
North America,
BUT, maximum snow depths and extreme snow storms could increase
even in the southern parts of Canada due to increased precipitation
Effects
↑ snow loads and possible damage

38. CC Parameters
(for Building Envelope Design)
Temperature
Precipitation
Snow
Wind

39. Wind
Research
Not much good historic data available because:…
Too few stations
Variation in equipment and capability (varying sensitivity and
extremes not logged)
Variable height of recording values
Shorter periods of records
Predictions (CC models not reliable as yet)
↑ gusting – (10% more hourly gusts in the 28 to 70 km/h
range)
Double the number of gusts > 90 km/h
Effects
↑ wind damage due to ↑ gust pressure

40. Other CC Parameters
(for Building Envelope Design)
Temperature
Precipitation
Snow
Wind
Wind-Driven rain
Freeze-Thaw Cycles
Severe Ice Storms
UV Radiation

41. Wind-Driven Rain
Research
Currently use DRWP taken at 10 m coincident with
1:5 year wind
Predictions (CC models not reliable as yet)
↑ gusting > 70 km/h with increased rain days/year would
↑ the DRWP by 2050
Effects
↑ incidence of leaking

42. Freeze-Thaw Cycles
Research
Modelling not good at or near freezing point
Predictions (CC models not reliable as yet)
↑ in F/T cycles in short term as overall temp increases
↓ in F/T cycles by 2050 as temp continues to increase
Effects
↑ incidence of F/T damage in near future
↓ in F/T cycles and potential damage later

43. Severe Ice Storms
Research
Unique meteorological conditions produce ice accretion
Predictions (CC models not able to predict freezing rain as yet)
Effects
↑ physical load
↑ falling ice risk

44. UV Radiation
Research
UV-B component damages synthetic building materials such
as plastics as well as natural wood and rubber
Predictions (CC models not able to predict UV as yet)
Further Ozone depletion will increase UV radiation
Effects
↓ service life of affected materials

45. What else would we like to know to
better design for Climate Change?

46. Temperature
For A/C and structural requirements
# days/year >30°C, >35°C, etc.
30-year extreme high temp
Cooling Deg. Days
For heating and structural requirements
# days/year < -20°C, < -30°C, < -40°C
30-year extreme low temp
For Ventilation and fire safety design
Impact on air buoyancy and stack effect

47. Precipitation (Rain and Snow)
Rain frequency, intensity and duration
Snow frequency, intensity and duration
Freeze/Thaw events & cycles
# wet days per year
Exterior air moisture
Extreme annual precipitation
# days/year > 25 mm rainfall
Maximum consecutive dry days/year
# days/year with severe ice storms (freezing
rain) > 4 hrs, > 6 hrs, etc.

48. Wind-Related Parameters
Average # hours/year with gusts
> 70, > 80, > 90 km/h, etc.
Extreme wind pressure due to localized or
unusual events
Hurricane and/or tornado event frequency /
intensity
Convective winds from severe thunderstorms
Sidewalk level wind effects

49. Design… yes… but
Who else is listening?
Since the IPCC has made several statements on
Climate change.. Like…
“Warming of the climate system is unequivocal
… the atmosphere and ocean have warmed,
the amounts of snow and ice have diminished,
and the sea level has risen”
Intergovernmental Panel on Climate Change
(IPCC)

50. Financial Institutions are Taking
Note
“The combination of the weight of scientific
evidence and the dynamics of the financial system
suggest that, in the fullness of time, climate change
will threaten financial resilience and longer-term
prosperity. While there is still time to act, the
window of opportunity is finite and shrinking.”
Mark Carney, Governor of the Bank of England

51. Financial Institutions May Decide
Though no announced protocol exists…Funding
for mortgages and refinancing of:
Resource development, manufacturing, and other
business that are carbon intensive may not be a
good investment risk
Building projects with no risk management plan
may not be as attractive an investment

52. Insurers are Taking Note

53. Insurers may be Limiting Coverage

54. Overall What will Codes have to
Address
1. Acknowledge that Climate Loads will change and these will
require site-specific modeling and design based on available
information,
2. Building Resistance will change due to resilience issues which
will (in near-future codes), be a design requirement,
3. Future, codes (should) require designers to make an
assessment of “Vulnerability” of Building Components to
changes in Load and Resistance. e.g. (PIEVC or other risk
assessment protocol).

55. Other Issues to Address
1. Catastrophic events (which designers may not be able to
accommodate in building design) may create large, uninsured
losses.
2. Designers and codes should consider where buildings are sited,
what the impact of an extreme event may be on the building,
and how the building can recover from such an event.
3. Design codes and standards take a long time to catch up to
available knowledge.

56. Other Issues to Address
Regardless of the glacial pace of codes and standards, design
information will be coming available and liability for building
performance will be attached to that knowledge (or lack thereof)
As my family moto says….Prima Prepara Domum
Which means “first protect the home” a.k.a
“Cover your Ass(ets)”

57. Discussion