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OSB Interior Wall Covering

StephNow

Registered User
Joined
Oct 20, 2009
Messages
75
Location
Home of Larry Holmes
I have someone who wants to finish the inside of their single family dwelling with OSB. I am of the belief that this is not a good idea and I'm not interested in permitting. What do you think?

Pennsylvania SFR under the 2009 IRC.

Thanks!
 
Since we are under the 2003 edition, I would use:

R309.2 Separation required.

The garage shall be separated from the residence and its attic area by not less than ½-inch (12.7 mm) gypsum board applied to the garage side. Garages beneath habitable rooms shall be separated from all habitable rooms above by not less than 5/8-inch (15.9 mm) Type X gypsum board or equivalent. Where the separation is a floor-ceiling assembly, the structure supporting the separation shall also be protected by not less than 1/2-inch (12.7 mm) gypsum board or equivalent. Garages located less than 3 feet (914 mm) from a dwelling unit on the same lot shall be protected with not less than ½-inch (12.7 mm) gypsum board applied to the interior side of exterior walls that are within this area. Openings in these walls shall be regulated by Section R309.1. This provision does not apply to garage walls that are perpendicular to the adjacent dwelling unit wall.

However I see that 2009 does not require this anymore? So I see nothing that prohibits OSB for an interior finish.
 
MJ has it.....if it meets the requirements it does not matter what anyone likes....like OSB.

I had a DSW shoe store where the rear "feature wall" is spaced cedar boards and looks like a fancy pallet....I know it would burn like crazy, but there was nothing I could do about it.
 
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snowroski said:
I am of the belief that this is not a good idea and I'm not interested in permitting. What do you think?
I think you're walking a slippery slope.

Code says it's okay. Unless you have an ordinance or amendment prohibiting OSB as an interior finish, they can do it.
 
steveray said:
MJ has it.....if it meets the requirements it does not matter what anyone likes....like OSB.I had a DSW shoe store where the rear "feature wall" is spaced cedar boards and looks like a fancy pallet....I know it would burn like crazy, but there was nothing I could do about it.
We have the same interior DSW here.

However, commercial may be a different animal. OP specifically notes project is SFR, IRC.

IBC and combustible finish requirements vary. See §803
 
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Any foam insulation?

R316.4 Thermal barrier.

Unless otherwise allowed in Section R316.5 or Section R316.6, foam plastic shall be separated from the interior of a building by an approved thermal barrier of minimum 1/2 inch (12.7 mm) gypsum wallboard or an approved finish material equivalent to a thermal barrier material that will limit the average temperature rise of the unexposed surface to no more than 250°F (139°C) after 15 minutes of fire exposure complying with the ASTM E 119 or UL 263 standard time temperature curve. The thermal barrier shall be installed in such a manner that it will remain in place for 15 minutes based on NFPA 286 with the acceptance criteria of Section R302.9.4, FM 4880, UL 1040 or UL 1715.
 
A local SIP manufacturer uses OSB on both sides of his panels. Framers set the panels, then the hangers come in and hang the rock right over the interior OSB.

I see no code problem with that, or the OP's situation.
 
DCA 1 2010 has osb at flame spread of 86 to 150 for 7/16 and less than the 450 for smoke. Sadly I have encountered this issue before and I too was a little surprised to find it met the criteria.
 
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