Plywood clips in new home construction
We are finally building the house that I have been planning for the past 3 years.
We started with framing from a Shelter kit because I had the naive notion that my brother and I could frame the house. Fortunately I have a very good contractor and carpenters who have been doing the framing. I go by everyday and make sure that all the seams are sealed well.
We are now putting on the roof sheathing to try to protect the framing from the record-breaking July rain in the Southeast (most ever in recorded). They are using plywood clips because the joists are 2 ft apart.
It seems to me that these clips leave pretty big gaps between the sheets of plywood. Are they really necessary?
We are taping the exterior seams with a vapor permeable tape from 475 building supply. And I am caulking the interior seams as well. I just wondered about the necessity of these clips?
What do you think?
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Replies
Lucy, only your code can tell you whether they are required or not. It depends both on the spacing of you roof framing and the thickness of your sheathing. An alternate approach which is a lot more time consuming is to screw scraps of plywood at mid span. This acts in the same way but might not pass inspection.
Thank you, Malcolm. I just saw those gaps and I'm thinking why would deliberately put those things in there? They are supposed to be there as a part of the kit so I assume they are required. I think scraps of plywood would decrease my space for insulation and be more problematic.
I've got everyone on board with taping gaps. As I am the Air Sealing Specialist (as Terry Nordbye described himself in a JLC article), I go back and caulk the interior gaps.
Thank you.
Clips are for 24" spacing. Zip 5/8 t&g needs no clips. You bought price not best.
The gaps are for expansion/contraction. Not an insignificant concern - you can often see the plywood edges telegraphing through asphalt roofing. Caulking the seams could interfere with that (in addition to being of dubious value). You're over-worrying. The tape will be fine.
Lucy, if you want to see how the clips help go up on the roof with one one of the heavier framers, have him step on the edge of one sheet at midspan and see how the clip makes both sheets move together, not independently. This will keep your tape in place too. They are particularly important where partial sheets have been used. I have gone through roof sheathing twice even with clips in place. It hurt!