I am going to be gutting and re-doing my sunroom in the Spring. It is an ad-on to the house, so 1 wall is original 1958 siding, one wall is particle board covered in T-11 siding (old garage exterior), and then the other two walls are exterior walls currently covered in what looks like wood paneling or some sort of thick cardboard / thin wood. The room has a cement floor, with carpet over it.
Basically, the room is weather tight, but I would imagine the room gets more moisture in it from the old windows (only windows in the house that aren’t modernized), and the fact that the cement floor extends out to be my back yard deck. I am going to gut, and then strengthen where needed, replace any rotted wood, and then re-do the interior walls. Would drywall be sufficient, or should I use something more moisture resistant? I could also go easy, and since it’s not really a room, but a bonus sunroom, just use T-11 on all the walls, and paint it a bright color.
What are your thoughts. The room is about 10 x 10.
If you are planning on heating the room you need to be conscious of condensation and hence a vapor barrier (3-10 mil. plastic between insulation and drywall). Insulated or not, drywall is a cost effective option with moisture rated version available. Unless you have water penetration, I think drywall would be sufficient. Seal the concrete as well as you can to prevent moisture wicking and try to install the drywall and trim off the floor just a bit. Textured or T111 is a commitment and hard to change if your tastes vary.
The room is not, and will not be heated, just trying to make it more classy. No insulation out there, but I did siding last year, and the exterior was wrapped in tyvek, and then vinyl siding over that.
your best option would be a fiberglass fronted gypsum product like densglass from GP…it is basically an exterior gypsum sheathing which can be finished similar to regular gyp board. unfortunately you’d be paying a premium for it. another option might be a concrete board product which would hold up well to the temperature changes and wouldn’t foster mold growth.
in any case since you don’t have insulation and the space is going to essentially be the temperature of the outside, if you use a gypsum product with any kind of paper in it, you need to let the wall breathe. keep the board at least 1/2" up from the floor and if you put any trim at the bottom keep that up off the floor as well. if you can figure out a way to vent the stud cavities at the top that would be beneficial to allow air flow through the walls so you don’t get moisture building up on the back side of the gyp board. i would recommend some kind of indoor/outdoor carpeting, something without much of a backing that could hold onto much moisture.
ultimately what you have is no different than a covered outdoor space, you won’t have any direct weather on any of the materials but you want to keep moisture from staying around for too long.
I know, that is why I am asking what material would be best. I may just do a T-11 style board up on all 4 interior walls, and then paint it a nice “woody” color.
On my laundry room with cement floor and @ grade I used cement board up to waist high all around then moisture board up. Hardibacker, wonderboard, durock… something along those lines.
qikz, I heard that you’re not supposed to use a barrier like polyethylene on interior walls because it ends up trapping moisture between tyvek/foam board and the plastic. then as the cold air meets the warm it condensates and drips down your studs since it can’t breathe easily. Unless you live way up north where it’s dry and cold consistently. Instead I was recommended a vapor retarder like kraft paper. I intended to plastic wrap the entire inside of my house then drywall over it but was told that’s a no no. What’s your take on this?
This is actually coming from an inspector, not a home depot dummy.
My end solution was to avoid a vapor retarder on the inside of the house all together, and instead have a strong vapor barrier on the exterior.
We did a complete rebuild if a fire damaged home in West Seneca a couple years ago and subcontracted the insulation to a large well known insulation contractor. Did the same for a 3500 sf. addition project last summer. Same subcontractor type arrangement, different company. Both used the plastic vapor barrier on the walls as it’s easier to install the walls with unfaced and ceilings with kraft faced. No building inspector has ever had a problem and no architect / engineer has ever mentioned a problem. I’ve never had a callback on any project referencing “weeping” of moisture down the walls. Tyvek is designed to “breathe” or release moisture out, but not in. No matter where you live, you will always have variation between interior and exterior temperatures.
I don’t think you’d really notice it if it were happening. The plastic would be doing it’s job and keeping the moisture out, so you’d never notice it until someone pops a hole in the wall and sees the studs far far down the road. It was my understanding tyvek was mainly not the concern, but more so the foam going over it… being tongue and grooved, then sealed together. Couple that with tyvek and whatever else is being put on the house at the time and then that’s where the problem lies. He didn’t say I wasn’t allowed, just recommended away from doing it. Since he’s the one signing the papers, I did what he said
As far as your situation goes neon… My dad once told me to put down the decking material on the bottom part for the wall. Not pressure treated wood, but the fake manmade type of wood they use on decks. He said to put that on the bottom, then drywall above that. I ended up just using cement board though since I didn’t want to have a piece of wood on the bottom of my floor… But be careful if you try to blend cement board and drywall. Some cement board comes in .5" and some is .42"
Well you could probably just do the t-11 osb and paint it a bright color then. and use azek board or something for the interior trim around the windows. It will kind of be like an inside out room, ha.
the best thing would probably be to tear everything apart and then assess the situation
he’s not insulatiing so it doesn’t matter what or where a vapor barrier or air barrier (tyvek) exists…since the temperature inside and outside are essentially the same there is no dew point to worry about occurring within the wall construction so you don’t have to worry about water vapor transmission through the wall.
