Did you leave a gap when installing OSB on you shop walls?

[Stuart Welsh]

I'm about 60% done installing OSB on the walls of my new shop then it hit me…..somewhere in a discussion on OSB I seem to recall a rep from one of the OSB manufacturers offering advice on installing and painting OSB. In that post I think I remember him advising to leave 1/8" space between panels. I know that is a consideration when installing decking for a roof and sheathing but how critical is it when installing on an interior wall that will be painted?

Have you installed OSB on your walls and if so did you leave a gap between panels? More importantly if you did not leave a gap have you experienced any issues? Do I need to get my palm router or dremmel out and make gaps??? UGH.

Thanks for your input.

[Charles Wiggins]

Have you installed OSB on your walls and if so did you leave a gap between panels? More importantly if you did not leave a gap have you experienced any issues? Do I need to get my palm router or dremmel out and make gaps??? UGH.

I have a basement shop that is subject to swings in ambient humidity, and I primed and painted my wall too. I didn't leave any intentional gaps, and nothing near 1/8" and I've had no issues. I just didn't go out of my way to make the gaps disappear completely. OSB is pretty stable because it's random cross-grain, you just gotta keep it dry. My main concern was that it not be in direct contact with the concrete floor to wick moisture, or that it might get wet if the water heater started to leak, etc., so I used 1/2" shims to keep it up while I screwed it on, and then covered the gap at the base with PVC molding.

Addendum: It's been three years now, and last year was one of the wettest summers we've ever had. If it was going to be a problem, I'd have seen it by now.

[Stuart Welsh]

Thanks, you've eliminated a time consuming chore I was not looking forward to. Did you do anything to hide where the panels meet? I'm considering screen moulding.

[Charles Wiggins]

Thanks, you've eliminated a time consuming chore I was not looking forward to. Did you do anything to hide where the panels meet? I'm considering screen moulding.

No. I have a very utilitarian attitude toward all things shop related. The OSB was to cover the insulation, sound mitigation, and provide a mounting surface for tools. The white paint is to reflect light so I can see better. The molding at the bottom of the wall was to keep down on dust and to keep from having to crawl under the bench to retrieve nails, screws, and the like. Strip molding to cover the gaps would just be more work and something else to work around when I wanted to mount things to the wall.

[Roy Harding]

My shop is finished with painted OSB as well. Like Charles, I didn't leave any gaps (at least not on purpose) and haven't had any problems in five years. It's worth noting that my shop is heated 24/7 so there are no great temperature changes. I'm not sure what would happen in say an unheated (or only heated part time) shop.

[Michael W. Clark]

OSB basement shop walls here too, no "intentional" gaps, and no problems.

I haven't heard of leaving the gap in roof sheathing? I used to help frame houses as summer work, and we never left a gap on roof sheathing or if installing on the walls. We used the metal clips between the rafters as necessary, but butted everything tight. That was about 20 years ago, so maybe things have changed?

Mike

[Shyang Huang]

Someone else asked and answered exactly the same question just a few days before this thread appeared:

http://www.sawmillcreek.org/showthre...g-all-builders!

For excellent video installation guides, check out:

http://www.norbord.com/na/resources/how-to-videos


If I remember correctly, in one of the videos it is stated that the 1/8" gap is factored into the manufacturing of the boards. Use 10 pennies for spacers. Use H-clips where applicable, but they do not replace the spacers. If it were me, I would do install per manufacturer's instructions. But that's just me.

[Steve Meliza]

Unheated attached garage with unpainted OSB butted tightly together. No issues two years later in a very wet climate.

[Stephen Musial]

OSB in garage in St. Louis. -20 to 110 temp swing (and just about the same for humidity). Only in the last year did I totally enclose the shop are of the garage (my wife still wants to park in there for some inane reason). OSB on entire garage has been in place tightly butted for 12 years with no problems.

[Randy Gazda]

I left a 1/8 gap as per makers instructions,7/16 OSB on exterior wall. I have watched the gaps swell shut and reopen during a wet/dry winter weather cycle.

[Jim O'Dell]

Close to 8 years on a detached shop. OSB primed with 2 coats of Kilz latex primer. Close enough to white for me. I put the rough side out for a little texture. I used caulk on all seams and butted all the joints. After screwing the panel down, I went back with a putty knife and raked the squeeze out on all the seams. The didn't disappear, but it blends pretty good. I also did this to the OSB on the ceilings. No issues at all, and the shop is not heated or cooled. Jim.

[Jim Andrew]

Mike, the clips created your gap on the roof, ends don't hurt you, it is the edges where the sheets butt between the rafters, if they are laid tight together, sometimes they will buckle up slightly and make a bump in the roof. Shows more than you would think, and complaints about the bumps caused some roofs to be replaced, and cuts to be made between sheets to create a gap. The clips take care of the problem, they create a gap and tie the edges together.

[Thomas Canfield]

I used Smart Panel (OSB exterior with primed surface) for current and previous shop installed with headed nails. Both had the panels butted without a dedicated gap. The seams in earlier shop were covered with screen molding and it was a pain when mounting any flat surfaces to the wall. My current shop has a rolled on semi-gloss latex paint over the primed surface and no joint fill. The seams are not a big objection, and it is a workshop. I would recommend avoiding a molding application to seams, but use of caulk if want to fill any gaps. I did install a base molding to cover any gaps at the floor.