Fire/sound/thermal abating alternative to plywood behind vertical T&G paneling
nickangiolillo
| Posted in Construction Techniques on
I’m renovating a 1970s house in the Pacific Northwest which has typical 2×4 to 2×6 wood framing (interior and exterior), and a good portion of the interior wall/ceiling finish has a layer of clear cedar tongue and groove fastened to plywood (fastened to the framing). The walls are up to 14.5′ tall in some places, and the boards are that long, running vertically from floor to ceiling.
The paneling sadly has been painted by a past owner and my goal is to bring it back to original finish. After some tests, I’ve judged that carefully taking the paneling down and planing the top 1/16th or so off to remove the paint before re-installing is the best move.
While the paneling is off, I’d like to improve sound transmission, fireproofing, and insulation in the wall.
Instead of re-installing plywood, I thought to use a different product to help with all of these factors without increasing the thickness of the full wall assembly. Some ideas might be drywall with thin horizontal furring strips over for the T&G to nail into, OR blocking behind drywall, OR some type of fiber/rock/cement board that can hold finish nails (structo-crete?), OR… something else?
If this were your house, what would you do?
Replies
Try paint remover. The chances of removing all that t&g without damage are slim, and finding some replacements might be tough. You will also need lots of planer knives, paint is pretty hard on planers. You will also have to sand all those boards once they come from the planer, so a drum sander would be a good machine to have as well.
I have done some tests with paint remover. It works on the trim boards ok but on the paneling the paint really sucks into any areas of open grain on the more plain sawn pieces. To do this without removal I feel like it will be hell on my shoulders to paint, scrape, and sand and I’ll be on scaffolding a lot. So, that’s why I figured taking it down would work best. My dewalt planer takes off the paint layer easily and yes I figure I’ll go through quite a few blades and need to get a drum sander for an even sand as well.
Is the T&G cedar painted, or is it stained with a white stain? From the picture, it looks like it was a white stain... If so, could you just stain it with a cedar color? ( I can't imagine the work involved in carefully taking down all that T&G material, running through a planer, sanding it, and reinstalling...
If you decide to take down all those T&G boards, and you don't want plywood as the substrate, what if you used drywall with 1/2" plywood nailing strips inlaid horizontally between 2' strips of drywall? You could also beef up the insulation in the walls using RockWool, which would improve walls thermally and reduce sound transmission...
Hi Nick,
Oooof, you've got quite a project on your hands here.
I have a couple of questions to help guide the discussion:
1.) Is the area in the photo the only room you plan on tackling or are there multiple rooms?
2.) It sounds like you've done some exploratory demo to figure out the layering of the interior wall finish - what insulation is currently in the exterior stud cavities?
3.) How's the condition of the backside of the paneling? If you're considering removing it to plane/sand the paint (or opaque stain), could you save yourself a step and reinstall it with the unpainted side out?
4.) This wouldn't solve the insulation/fire resistance issue, but have you considered doing a test area with a powered drywall sander (Planex, or similar)? It wouldn't remove all of the paint, but could yield a very attractive result, depending on your aesthetic. Similarly, if you have a lot of SF to deal with, you could interview a couple of dry-ice "sand-blasting" contractors and see if they'd take it on. The nozzle type and pressure would have to be just right to avoid a disaster, but the finished product would look interesting as the abrasive would dig deeper into the softer grains, and you'd be left with a subtly 3-dimensional paneling.
5.) What is your home sided with? Depending on your existing siding, blown-in insulation could be an option to increase your thermal resistance.
6.) What's most important to you: Cost, time, final appearance, sustainability (re-use of existing).
Fun problem to have if you ask me. Good Luck!
1. There are multiple rooms. Probably about 1200-1500 sq feet of rooms with walls and ceilings with the T&G cedar, as well as all the trim which is cedar and painted.
2. Actually haven't done this demo yet to pull off any of the plywood on exterior walls. On interior walls, there is no insulation. There is some fiberglass batt in an attic off one part of the house, so I think it may be batts in the exterior walls.
3. Good idea - I may be able to just flip the boards in some areas, but there are a few long boards that go floor to ceiling and have an angle cut against the ceiling, so I wouldn't be able to flip those. Considering this route for sure to save time.
4. Haven't considered that yet but good idea. I did reach out to one dry ice blaster conctractor but didn't get a response.
5. The home is sided in the same material, painted! Vertically installed T&G cedar. I don't know if there is some sort of rain screen behind it but I expect not.
6. Most important factor is appearance, with the assumption that I will do the work myself to keep costs down. So, whatever I do here needs to be DIY-friendly, but since I'm not time-bound and can go room by room, I'm willing to take a slow approach.
From the feedback so far, if the paneling does come down, it seems drywall installed behind the paneling could be a good firebreak. I would just need to have something to nail into. So, maybe blocking in the stud bays, then drywall, then paneling that can be pinned to the blocking.
For sound mitigation, insulation in all walls between the studs, and acoustic caulk around the drywall seams. Open to any extra ideas for sound mitigation here that doesn't really change the wall thickness dramatically.
This is seriously so much work. If you go through with it, consider the helical cutterhead upgrade. Quieter, more durable, better end result, probably faster.
Noise transmission: consider a standoff system like isoTRAX Soundproofing System
Insulation and fireproofing: insert a thin layer of mineral wool behind the drywall standoffs? Just consider that it might decrease the effectiveness of a noise transmission standoff system (probably ask the manufacturer).
I wonder if you could just use a thin layer of external semi rigid insulation and reinstall the boards right on it (with vertical solid furring strips at the ends and the middle).