Can I skip sheathing the inside of a wall because of expenses or is sheathing necessary? I’m planning on sheathing only the outside wall.
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Replies
Nicky,
You need to contact the designer (draftsman, architect, engineer) that produced the construction drawings and discuss the omission of the interior wall sheathing with them. Assuming the interior sheathing is OSB, the designer may have specified the additional sheathing to withstand lateral loading, etc.
Hello, I am the designer, and I wanted to know if it is possible to do so without or if plywood is relied upon for the buildings stability. An alternative would be drywall for the inside of the house, but the outside of the house would be plywood.
Do your plans show sheathing on the inside? In 50 years of building, I've never seen interior sheathing.
likewise.
edit: from a guy in Ohio that is ignorant about all there is in construction.
Hello, I'm not using plans. I've seen videos of people using plywood (sheathing) on the walls of the inside of the house, and wanted to know whether or not that was necessary.
Where are you located? If you're not in a hurricane, tornado, or earthquake zone it's not common to use shear walls in average home construction. We've used them twice in Vermont for very specific reasons, holding the lateral force on an open design ceiling on a 2nd floor. We built the shear walls dividing the bedrooms and hall (all interior walls) to keep the eaves walls and roof from spreading. So, there are even times when it's applicable outside of those examples I mentioned.
Sheathing on exterior *and* interior walls is done all the time, they're known as shear walls, and used in earthquake, tornado, and hurricane and other high wind areas. If you're in an area that might need the extra resistance, I wouldn't be eliminating it based on any advice you get from a stranger on an internet forum (especially from anyone who has never heard of them!). As someone else suggested, ask your designer/engineer.
Hello, would drywall be a good alternative other than using plywood on the inside walls?
That entirely depends on the shear loading of the wall. In my experience an engineer can substitute metal strapping for plywood sheathing for most interior shear walls.
No offense but Nicky obviously isn't an engineer and we have no clue where Nicky is building this house so no clue as to whether interior sheathing is needed or not. I've been building and repairing, among others, plenty of oceanfront homes in the highest hurricane wind zones of Florida for 50 years. I've never seen interior sheathing in any of them. I've seen some small shear panels next to garage doors but that's it. So, I'd say that interior sheathing is unusual and probably rarely required. Hopefully, Nicky will hire an engineer to create the final plans.
Hey Florida, I've been watching videos of cabin home construction on YouTube like,
https://www.youtube.com/watch?v=b3XqNW3Bd10&t=1813s. In this video he puts plywood on the inside of his home as well as the outside.
Nicky,
I don't see where he's used plywood inside at all. He has installed what looks like 1 X 8" T&G planks which are fine on interior walls. It goes up fast but is pricy. Planks are a very common interior wall and even ceiling material and provide some measure of stiffness but are not usually structural in nature. The reason most houses use drywall is that it's relatively inexpensive, looks nice, and takes paint well.
I think you’re seeing him install sheetrock on the interior walls that he doesn’t use t&g pine on. I don’t see any sheathing on the interior either.
I just saw this from this very magazine: https://www.finehomebuilding.com/project-guides/framing/how-it-works-shear-walls
Thank you!
The Florida Building Code: SECTION 2305
GENERAL DESIGN REQUIREMENTS FOR LATERAL
FORCE-RESISTING SYSTEMS
2305.1 General.
Structures using wood-frame shear walls or wood-frame diaphragms to resist wind, seismic or other lateral loads shall be designed and constructed in accordance with AF&PA SDPWS and the applicable provisions of Sections 2305, 2306 and 2307.
2305.1.1 Openings in shear panels.
Openings in shear panels that materially affect their strength shall be detailed on the plans, and shall have their edges adequately reinforced to transfer all shearing stresses.
2306.3 Wood-frame shear walls.
Wood-frame shear walls shall be designed and constructed in accordance with AF&PA SDPWS. Where panels are fastened to framing members with staples, requirements and limitations of AF&PA SDPWS shall be met and the allowable shear values set forth in Table 2306.3(1), 2306.3(2) or 2306.3(3) shall be permitted. The allowable shear values in Tables 2306.3(1) and 2306.3(2) are permitted to be increased 40 percent for wind design. Panels complying with ANSI/APA PRP-210 shall be permitted to use design values for Plywood Siding in the AF&PA SDPWS.