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training report

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

ing drying.

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

rot conditions.

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.”

418

July/August 2014 | Home Builder Magazine Canada  

July/August 2014 | Annual New Product Showcase. The 13th Annual Product Showcase shines a spotlight on the latest in building materials, new...