iDRY Vacuum Kilns

Sponsors:

What, if anything, to put under interior wood paneling

Started by alan gage, September 04, 2019, 09:20:17 AM

Previous topic - Next topic

0 Members and 3 Guests are viewing this topic.

alan gage

I'm currently building a new wood shop for myself (28x39) and will likely be using boards to line the interior walls and possibly the ceiling as well. No tongue and groove or shiplap, just butted edges. I've been thinking it would probably be a good idea to put something behind the boards to slow down air movement through cracks that develop and to keep any insulation from showing through.

Sheetrock seems like the best choice. Would be a very good air barrier and provide some fire resistance. But also expensive, time consuming, and not very fun to put up.

Other choices would be something like 15lb roofing felt or rosin paper.

I live in a cold climate (think Minneapolis) and the building will be heated in the winter but not cooled in the summer. The walls are stud framed 2x8 with exterior board and batten.

Any thoughts appreciated.

Thanks,

Alan
Timberking B-16, a few chainsaws from small to large, and a Bobcat 873 Skidloader.

YellowHammer

We use roofing felt.  It provides an air seal and it's black, any gaps in the wood just look like a deep shadow.  I don't think the bugs particularly like either, it being saturated in a black tar type material.  
YellowHammerisms:

Take steps to save steps.

If it won't roll, its not a log; it's still a tree.  Sawmills cut logs, not trees.

Kiln drying wood: When the cookies are burned, they're burned, and you can't fix them.

Sawing is fun for the first couple million boards.

Be smarter than the sawdust

BradMarks


curved-wood

A friend had put some aluminum foil under an interior siding, not so dry wood with butt joints. If you move in night time with inside light on, it was just like light flashing here and there. Weird feeling...no need to take an acid cap :)

alan gage

Quote from: curved-wood on September 04, 2019, 02:52:41 PM
A friend had put some aluminum foil under an interior siding, not so dry wood with butt joints. If you move in night time with inside light on, it was just like light flashing here and there. Weird feeling...no need to take an acid cap :)
That's good to know. Aluminum foil wasn't even on the list so I'll write it down and cross it off.
Alan
Timberking B-16, a few chainsaws from small to large, and a Bobcat 873 Skidloader.

Nebraska

My shop is one bay of an old open front pole shed. I took spray foam (canned) sealed gaps then used fiberglass batting for the walls and ceiling then ripped plywood nailers and used rigid foam over that. It's supposed to get covered with the old corrugated steel I took off when I put the new roof on.  It will stay above freezing til it's around ten below with a little 110 volt ceramic space heater I think it's 19x28. I am just a little warmer than you. Insulate the heck out of it, I would use heavy plastic like silage tarp on the inside as a moisture barrier and felt under the siding so the building can breath. Tyvek /typar, and the like work well too but heavy felt is good too and much cheaper.

Brad_bb

Professional spray foam will provide you with great insulation and moisture barrier.  I recently built a new shop with 2x6 wall construction with first closed cell spray foam, and then open cell on top of that.  If you kept the doors shut, you wouldn't need AC in the summer.  The slab is insulated too.  I love a super insulated building.  Low heating and low cooling costs. The only reason I'd put something behind the paneling is so that you had something dark so when you have a check or small gap, you'd see dark and not the sheathing behind it.  I have a stairwell I'm doing in wide oak barn boards.  It's sheathed in plywood now, so I'll probably end up painting the plywood or you could do a roof felt there that is black.  I think the upfront cost of the sprayfoam is worth it (done right of course).  Once it's in, you won't regret it.  I think the foam is fire retardant too?  There is some sound deadening property too.  For interior walls I used mineral wood aka rock wool.  Not only a great insulator, but a great sound deadener, and fire proof.
Anything someone can design, I can sure figure out how to fix!
If I say it\\\\\\\'s going to take so long, multiply that by at least 3!

Don P

Wandering off the op a little but good to keep in the back of mind;

Foam is combustible. It is required to be covered by a 30 minute barrier in accessible places. Then you get into interpretation, this can really vary. 3/4" wood is considered to be a 30 min barrier. T&G is not uniformly 3/4 thick and square edged boards have gaps. Some inspectors consider board covering to be good enough, in other jurisdictions they require 1/2" drywall, sometimes taped, under the wood. If this is to be inspected it's best to ask in advance.

QuoteR316.4Thermal 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 a material that is tested in accordance with and meets the acceptance criteria of both the Temperature Transmission Fire Test and the Integrity Fire Test of NFPA 275.
That is from the 2012 IRC, on 9/1 VA switched to the '15 but it reads the same, some of you are on the '18, I believe it is also unchanged. The safe bet is above, otherwise good to clear it first.

Energy wise if you do batt insulation it is not a bad idea to drywall or ply under board finish to limit air movement. A ply or osb base allows you to nail anywhere which opens up the opportunity to run boards in any orientation, or an intarsia kind of wall.

LandslideLyndon

You are correct in thinking that sheetrock is your best choice. 5/8" Type X is best, providing a 1hr fire rating. 1/2" sheetrock will provide a 30 min. rating. You wouldn't have to "finish" the drywall, a simple "firetape" would suffice.

rjwoelk

The way it is done up in canada is always put a vapour barrier between the insulation and your interior sheeting. This keeps moisture from inside getting into the insulation and causing a big mold problem. The exterior uses a product like tyvek to help from the outside but it breathes to allow the insulation stay dry as to what ever the outside MC % is.This is code. 
Like Don says you need a fire resistant wall possibly . So check with insurance and building code. Even if you dont need it inspected, going by the building code may help you in the long run if you should ever sell or heaven forbid a fire and insurance is denied .
Lt15 palax wood processor,3020 JD 7120 CIH 36x72 hay shed for workshop coop tractor with a duetz for power plant

alan gage

Kinda forgot I started this thread. Still not the point of putting anything on the interior walls but getting close. I'd like to find someone to dense pack cellulose in the walls/ceilings but having a hard time finding anyone locally willing/able to do it. Checked on rock wool insulation but my local yard can't get it. Which leaves me with dense packing my own cellulose (BTDT once and not in a hurry to do it again) or fiberglass batts.

Leaning pretty heavily to putting sheetrock over the studs before wood paneling for fire resistance and to cut down on air movement. Materials are cheap enough (under $1k) and it will be nice peace of mind knowing it's back there. It will also let me solidly cover up the insulation so that I can move on with other phases of the interior and then do the wood paneling over the winter after some/all of the electrical and heating are done.

Alan
Timberking B-16, a few chainsaws from small to large, and a Bobcat 873 Skidloader.

Bruno of NH

Lt 40 wide with 38hp gas and command controls , F350 4x4 dump and lot of contracting tools

alan gage

Winter came before I was able to get anything on the interior walls and it showed me there was a lot of air getting through the exterior siding and tar paper so I decided I wanted something on the inside to stop airflow. Sheetrock would have been ideal but the thought of sheetrocking the walls and ceiling was about enough to make me puke so I went with foam sheeting instead. The ceiling got 1.5" XPS and the walls got .75" low grade EPS. The XPS on the ceiling will make a good thermal break for the rafters. The 3/4" EPS on the walls won't give a lot of R value but was much cheaper and will stop air flow.

I installed them with a gap between the sheets and "caulked" it with spray foam. Seems to be doing the trick.

Finally starting to get some wood up on the walls. This was the first batch so now it's time to plane and rip the next batch.

One bad thing about the low grade EPS foam is that it crushes easily so I can't crank down as hard on the screws as I'd like for cupped boards.



Alan
Timberking B-16, a few chainsaws from small to large, and a Bobcat 873 Skidloader.

Thank You Sponsors!