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The Unvented Attic System

If you have read the first two Tech Talk articles, you have seen how Florida’s climate and some principles of science make us pay the price to remove heat, humidity and other undesirables from our indoor environment.

A totally new concept in insulation is coming to the rescue of our energy bills.

Foam insulation can be injected in the walls and sprayed in the attic to seal out the undesirables. In the attic, spray foam is applied to the underside of the plywood and roof truss assembly. This is called the roof deck. Soffit vents, ridge vents, etc are eliminated so that the attic becomes cooler, drier, and airtight. The temperature is decreased by 40-50 degrees.

So what is the advantage of having a cooler attic ? Think about what’s up there. No, not the Christmas decorations or your old high school sweater. We’re talking about the A/C ductwork!

You’re A/C chills air to about 58 degrees, then sends it up into the attic to travel to all the rooms of the house. If your attic is 140 degrees, the air being delivered to the house is compromised by 12-15 degrees before it ever reaches the desired room. That’s why we have hot and cold spots throughout the house.

A closed, conditioned attic keeps that cool air consistent in all the rooms of the house. A simple design change in the roofline of the living envelope can save energy, increase comfort, and may actually shield your family from all those undesirables.

See a visual demonstration of this principle »