Friday, February 13, 2009

Supporting Plywood On The Roof

My house is basically divided into two sections; a small section (dining room on the main, bedroom upstairs) and a large section (everything else). The roof trusses above the small section are spaced on 16" centers. The roof trusses above the large section are spaced on 24" centers.

When sheathing a roof, the plywood must be supported along the edges between the trusses. For the small section of the house, I used H-clips. They are in the shape of an "H", and you place them between the sheets of plywood between the trusses.

For the large section of the house, I've used a more old-fashioned method of nailing a length of 2x4 between the trusses. The edges of adjoining sheets of plywood are then nailed to the 2x4. This provides a bit more support than the H-clips, particularly when the trusses are spaced farther apart.


  1. How's that plywood holding up in the weather? We recently switched over to use AdvanTech sheathing on all the roofs we build. It's really cool because it can get wet without swelling. We also use tongue and groove now to eliminate H clips.

    You're making good progress on the house, I'm looking forward to seeing it when it's finished.

  2. Thanks Todd. I haven't had any problems with the plywood really. Most of it is covered with tarps. I've wondered too about using tongue and groove. Perhaps next time if I do this again.

  3. Well so far you're doing a great job. I'm quite impressed that you're doing this solo!