DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (
-   Building & Construction (
-   -   Any warnings for insulation in a bathroom? (

jayp 06-05-2008 07:12 AM

Any warnings for insulation in a bathroom?
I'm remodeling a bathroom in a 1940's house. I ripped all the plaster out and as usual, there's no insulation. I'm not really too worried about noise but one of the walls in the bathroom is exterior. Standing in the bathroom, I have 2x framing, then 1" plank sheathing, then some kind of old roofing felt, then the exterior wood siding. I was thinking of putting in faced r-13 fiberglass insulation and just stapling the paper to the 2x4's and then covering the wall with a plastic vapor barrier before I apply the tile backerboard. But then I started wondering whether the heat inside the walls would be trapped and possibly create moisture. Since the rest of my house isn't insulated, I could also just say forget it and leave it as is but I like to stick it in there whenever I can. Any ideas?

Termite 06-05-2008 08:00 AM

I'd definately install the insulation in the exterior wall. The paper face goes to the conditioned/interior side.

You are also right to install a moisture/vapor barrier on the face of the studs. I wouldn't be too concerned with moisture in the wall. Your old home's walls "breathe" enough that I doubt that will be an issue. You'd run a greater risk of moisture without it!

taty 06-05-2008 12:40 PM

fiber vs foam
3 Attachment(s)
I remodeled 2 bathrooms lately in my house which built 1927.
I used fiberglass in one, and pored in polyurethane in 2nd. Polyurethane won. No headaches with vapor barrier, and R-value is higher (24 for 4"). A bit more expensive and messier, but totally worth is.
photos of smaller bath are attached.

Maintenance 6 06-05-2008 12:45 PM

If your plan is to use a plastic vapor retarder, then use unfaced fibreglass. You don't want two vapor retarders in the same wall space. If you can't get unfaced, then slash the paper with a utility knife about every 3-4 inches.

buletbob 06-05-2008 04:08 PM

I agree you don't want two vapor barriers, you will have moisture between the two..

taty 06-05-2008 05:27 PM

spray on
If you will go with spray on polyurethane, you don't need any additional vapor barrier. It is easy if your walls all striped down to studs.

Knucklez 06-06-2008 10:08 PM

4 Attachment(s)
did you do the spray poly yourself? if so, can you provide more details on this product & process?

jayp 06-07-2008 05:44 AM

I'm going with unfaced due to time constraints! Thanks for the tips

taty 06-08-2008 09:39 PM

to Knucklez
1 Attachment(s)
Yes, I used a Tigerfoam.

I used Slow Rise formula, it works well.
Infrared inspection showed significant difference in r-value to compare to fiberglass.
I was poring it into the walls, most of them are stucco from both sides, and I didn't plan to rip them off. It took some time to figure out how it works best, If you need any particular details, like how to make best openings for poring (will be easy to fix them later), how to avoid air pockets, ext, let me know.

atw58 08-03-2008 04:08 PM

Hi Taty,

In the winter, I can feel a draft where the floor meets the baseboard. Looking behind the air jet tub I see the vapour barrier has not been caulked to the bottom. It is just hanging loose.

How would the slow rise Tigerfoam help. Do you suggest pulling the baseboard and injecting foam to try and seal the leaks.


Big Bob 08-03-2008 08:43 PM

Taty is a what ever she says....

back in the 70's they tried the visqueen over the faced insul batts..discovered rain pocket...this is a don't do ... even worse in humidity belt down south....keep or allow insulation to have lowest possible RH for most efficient K factor..

4just1don 08-03-2008 09:35 PM

ONE tip,,,IF thats an OLD leaky window,,,start there first. Nothing worse than getting all done and finding yourself 'starting over'. if is a pretty new one,your on your way (my pics view fuzzy here)

All times are GMT -5. The time now is 08:50 AM.

vBulletin Security provided by vBSecurity v2.2.2 (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
User Alert System provided by Advanced User Tagging (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.

Search Engine Friendly URLs by vBSEO 3.6.1