To avoid these ads, REGISTER NOW!

OSB for interior walls - do I need an expansion gap?

Falcon67

Well-known member
Joined
Jun 11, 2009
Messages
18,371
Location
Merkel, TX
No gap on decking? I use the clips to make the spacing up there. I'd be much more worried about decking moving around because of the extreme temps than interior wall sheathing. My roof deck can go from close to freezing to 160F. Inside with R-13 wall insulation, only siding, no sheathing and no exterior building wrap, on even the hot days the long west wall only gets to low/mid 90s.

I'll also throw in that I once had a 4x8 piece of 1/4 OSB that covered a doorway opening on the shed. It was a dog exit blocker and nothing else. It was hung up just like it came from Lowes with no finish and faced due west. It was there for around 9 years and it never fell apart. It didn't look real pretty, but it stayed where it was put.
 
Last edited:
To avoid these ads, REGISTER NOW!

Brad1234

Well-known member
Joined
Aug 13, 2009
Messages
204
I live in Ohio. Finished my garage 12 years ago with 7/16 osb with no gaps. No problems so far.
 

LIVELY

Well-known member
Joined
May 8, 2010
Messages
362
Location
Illinois
remember--most insurance companies want any wall touching the house to be covered with at least 1/2 inch drywall with a coat of tape for fire safety.
if it is attached shop you might want to check on it:thumbup:
also--i just gap the sides of osb inside a garage--no problems in lots of years[some of the cheapy **** will wave no matter what you do with it]:lol_hitti
 

toyville

Member
Joined
Oct 20, 2012
Messages
22
In a garage i built a few years ago I decieded to finish the inside with OSB. The garage is 26x26 and the walls are 8 high and 16 ONC and so are the roof trusses. The walls are insulated with R14 roxul but I have not insulated the attic yet. all the OSB was installed at the same time early last fall with No gaps. This spring the OSB on the ceiling is bowing every wheres far more then i would ever thought possible. leaving even a 1/4 gaps would not be enough maybe an inch. The walls are fine and i'm thinking its because of the attic temps are higher even though the attic is well vented.

I want to blow in some insulation to see if that helps but it will be such a pain if it doesnt help and i end up needing to remove the OSB off the ceiling. As i'm sure the vapor barrier will not hold the blown in insulation up on its own.
 
To avoid these ads, REGISTER NOW!

bigguns69

Well-known member
Joined
Aug 23, 2011
Messages
411
Location
Iowa
My 36 x 50 shop is finished with OSB on the inside with no gap. Building has a temperature range from -20 to 115 degrees F over the course of the year. I have witnessed no buckling, movement, creep, in the structure over the years. Think about it like this, at the seem of (2) panels, you have a nail or screw about 1/2 from the edge for both sides, so the gap is suppose to allow material elongation on a total of 1" unsupported material at the edge?? I know the building trades support this, and it would make sense if the panels were allowed to float over their entire length, but you put a fastner in every 16 to 24" inches to mechanically fasten it to the base structure. Doesn't make sense from an Engineering standpoint.
 

383 240z

Well-known member
Joined
Dec 4, 2006
Messages
4,295
Location
Findley Twp. Allegheny Co.
My sheets were 1/8" shy of 4'x8' in each direction. I was always told that was for the H-clips when used on roofs. My walls are about 7' 6" so I was not worried about the height, I did use the clips on the walls, as I had them on hand. I lined up on every stud. Been that way for about 2 years now no issues with warping for me. I'm planning on doing the ceiling this summer I'll clip it as well simply because its cheap insurance, and I'll be hitting the trusses. Keith
 

dirttracker18

Well-known member
Joined
Aug 10, 2009
Messages
3,191
Location
Slate River, ON
This spring the OSB on the ceiling is bowing every wheres far more then i would ever thought possible. leaving even a 1/4 gaps would not be enough maybe an inch. The walls are fine and i'm thinking its because of the attic temps are higher even though the attic is well vented.

That is not due to gaps it is from the weight of the board itself and the span of the trusses.

OSB is stong in shear and does not handle weight on its flatside well.

That being said I am 24" OC and have not issues with sag.
 

ABADWILLYS

Well-known member
Joined
Nov 16, 2012
Messages
738
Location
Hudson Valley, NY
interesting read, i am just getting ready to put OSB on the botton 4' of my interior walls, it does say on my panels to leave a 1/8th inch gap but im gonna **** em tight i haveta cry when i read what you guys pay for OSB, 6.49 then i realize this thread is 2 years old OSB today at Lowes is 16.37 a sheet!!:shocking:
 
To avoid these ads, REGISTER NOW!
Top Bottom