Whether using roof trusses or stick framing a roof frame, if you make space above the exterior walls, your energy performance will thank you.
In working on the Professional Remodeler Model Remodel project with builder Ben Bogie, one phase was rolling trusses, and Ben specified raised heel trusses to keep the thick layer of insulation in the attic, well—THICK. In cold areas it helps prevent ice dams by keeping the roof cold. In hot places it helps the AC unit not have to work overtime. Nobody wants to pay time and a half if they don't need to.
Here are three quick and easy options to make space above the walls for insulation. Coming up, we'll look at some advanced options from an architect who specializes in high performance building and remodeling.
Manufactured roof trusses are a strong and efficient way to get a frame up fast. Because they can span wide rooms, there is clear space for a thick blanket of insulation.
At least in the middle there is. At the edges, the insulation can get squashed down pretty thin.
Some truss manufacturers improve on this design by raising the top chord, wedging a 2x6 block in, and gusseting it all together. This works well to boost the amount of insulation above the wall. It can get you up to a foot of insulation, which is much better than a squash truss.
Some truss manufacturers take that a step higher with a little stud under the top chord. You can specify whatever height you need to.
Better roof framing is not confined to engineered trusses. If stick framing is the plan, you can still raise the heel. Instead of running ceiling joists next to rafters, build the ceiling frame as if it were a floor and set a plate along the outer edge.
Now you can set rafters atop the plate for a solid roof with plenty of room for insulation.
However you get there, thick insulation in the roof is a great place to be.
—This video is part of an ongoing series on better ways to frame houses partly because the editor's first construction experience was framing houses.