The Ontario Spring Training Camp
By Jon Eakes
Wise people in a room full of contractors for two days The Ontario Spring Training Camp 2014 was a training industry response to the withdrawal of the Federal government from generalized building
effective R-values are what should be used in all construction. Temperature dependence of materials
science research and its dissemination. Without any need for political cor-
can have a 20 per cent impact on R-value,
rectness or respect for sacred habits, the presentations cut through tech-
reducing R-6 to R-4 in normal temperature
nical debates looking at which part of building science works in the field.
ranges. A return air grill has no effect on air currents beyond 6” from the grill. Start measuring static pressure, not air
ten to a coalition of those icons of our industry
Documented Session Statements Worth Meditating on:
that I have leaned on to get my building science
Building materials rarely fail—the hand that
Air conditioners need to change from
There was a large contractor turnout to lis-
writing, video work and teaching right for the
applies them is what fails.
flow, to plan for air “throw”. today’s 80:20 Sensible:Latent ratio to 50:50
last 35 years. These individuals are listed at the
Prime Peel & Stick to avoid Stick & Peel.
or even 40:60 because with our efficient
end of this article.
Wet happens. You can’t keep it from getting
houses, sensible loads are going way down
Two days of concise, simple and gamechanging presentations are impossible to distill in a short magazine article so let me just
wet; design it to dry! Temperature differences create the drying mechanism.
and latent loads going up; dehumidification is important. Computer models are never right but some
tease you, perhaps challenge some of your
Plywood lets moisture migrate to dry as
established procedures, while definitely open-
there is a radical vapour permanence
Modelling for retrofit has little use because
ing the door to new and more efficient or effec-
increase with increase in RH. OSB has
it is simply not accurate from poor data
tive ways for you to build houses.
very little increase in permanence, block-
collection to poor models; inspecting to
Get Your Priorities Straight – Above and Below Grade
can be useful.
identify major problems is more useful.
Mould growth happens at much lower
In performance, DHW, lighting, appliances
humidity/moisture levels than rot fungi.
and plug loads are all uncontrollable and
1. Water control layer
So avoid mould conditions and you avoid
dominate over what is left of energy use in
2. Air control layer
new house construction.
3. Vapour control layer 4. Thermal control layer It is obvious to most of us that you shouldn’t
Mould susceptible material rating: Tree –
The father of Canadian Dynamic Walls him-
plywood – OSB – chipboard – particle board
self, John Timusk, came out of retirement to tell
– Masonite – paper-covered gypsum.
us: “Mechanically draw air through walls only
insulate if you cannot control vapour. The
If you air condition, no plastic.
when the sun is hitting that particular wall.
other priorities are less obvious. Vapour con-
House wraps are a transitional technology
Negative house pressure is not really achiev-
trol is useless if you don’t have air control. Air control is useless if you don’t have water control, including drainage. Miss drainage and you miss it all.
16 Home BUILDER July/August 2014
waiting for composite panels. 1/64” will work for a continuous drainage layer, like DuPont DrainWrap. Thermal bridging is so important that
able because of opening doors and windows. You need ceiling level channels to mechanically draw from the wall directly and only when the sun is adding heat.”
Published on Jul 24, 2014
July/August 2014 | Annual New Product Showcase. The 13th Annual Product Showcase shines a spotlight on the latest in building materials, new...