How To Insulate Scissor Truss Roof
The finish ceiling option if you want to keep your exposed roof trusses visible then the easiest way to add some insulation is to add it to the exterior side of the finished ceiling.
How to insulate scissor truss roof. We cut one inch strips from the foam board and tack them to the truss directly under the roof sheathing. Then we fit a piece of foam across the rafter bay to create a one inch air space under the sheathing and we fit a piece of foam up under that channel at the outside edge of the wall plate sealing the foam board to the framing with gun foam. The right way to insulate attics and cathedral ceilings with batts using certain t. Scissors provides a cathedral or vaulted ceiling.
The boards are secured by a screw fixed counter purlin running from eave to roof ridge above each rafter or top chord. By keeping the insulation on the outside it hides it from viewers while still keeping the insulation trapped inside. Your two best choices are probably to insulate from above with one or more layers of rigid foam or nailbase or sips or to insulate from below with spray polyurethane foam. Purlins or tile battens are fixed to the counter purlin as per standard industry practice.
Flat the most economical flat truss for a roof is provided when the depth of the truss in inches is approximately equal to 7 of the. If you ended up with scissors trusses without raised heels. A variety of insulation materials can be used to insulate scissors truss roofs as long as. The screws secure the counter purlin to each rafter or top chord.
Most economical when the difference in slope between the top and bottom chords is at least 3 12 or the bottom chord pitch is no more than half the top chord pitch.