Rafter Sheathing Complete

June 6, 2021

This weekend we completed the rafter sheathing.

We really put the flashing tape to the test using it exclusively to assemble the box.

Ryan did most of the work, and thankfully was willing and able to navigate some very tight spaces to do so. This final area was a bit easier since we had attic access, but also harder because it required building a box to provide extra space for air ducts.

The bottom cap of the box will eventually have holes for one 14 in. and two 10 in. insulated flexible ducts to pass through it.

I used the flattest sheathing board I had, but because I left so little clearance and and the board was still somewhat cupped, it ended up making contact with the steel purlins above.

The center board is held up by three screws driven through the top and one driven through lower cap of the box.

To remedy this, we added a 2×4 down the center of the inside of the box, pulling the center of the sheathing board down, making it perfectly flat.

Even with the shortest bit and stubbiest drill, it was a very tight squeeze to get the screws in.

My daughter was able to get in to the tightest of spaces and operate the screw gun to attach the board.

I expect that without creating this clearance, the box would act as a resonance chamber and amplify the vibration from the roof during a rainstorm.

The result was about an inch of clearance, which will ensure no vibration from the roof transfers into the sheathing.

The interior space is getting quieter and quieter. We’re down to about a 32db noise floor and still have doors and much more insulation to be installed.

The rafter sheathing is finally complete. I have a few final spots to close up and then I’m ready for closed-cell insulation to be sprayed on the ceiling, gable ends, attic walls and center columns.