dshah65

Hello – I'm hoping I can get some good advice on my upcoming basement renovation project for the holidays. Any help is greatly appreciated.

Currently, I have a finished basement – it's ugly, mind you. I'd like to remove the existing interior wall panels, replacing it with drywall, and too, replace the fiber-glass insulation underneath with something better, and redo the whole thing. Essentially, I'd like turn my basement into a comfortable and nicely finished family recreation room.

My questions are regarding vapour barriers – once I remove the ugly interior wall panels, and the fiber-glass insulation underneath, should I find a vapour barrier underneath the studs? What if I don't (my house was built in the 1960's)? Does the vapour barrier go on top of the studs, above my new insulation (I'm thinking rigid foam) or should it be beneath the studs, directly separating the interior brick wall and the studs? Currently, there's no water damage or noticeable moisture problem – only that my basement is very cool.

Also, once I remove everything, should I treat the brick wall with any sealer?

If I don't find any water vapour barrier, should I remove the studs and start fresh? What's the danger if I have a vapour barrier on top of my insulation, beneath new drywall if an existing old vapour barrier exists beneath the studs and existing brick wall?

Thanks in advance!

Best,
DS.

cortell

When it comes to the ever confusing topic of vapor barriers, much like real estate, it's all about location, location, location. Before anyone can offer sound advice on this subject, you need to make your location known. Best way is to note it in your profile, so that it's automatically available for all future questions.

cortell

BTW, I believe vapor barriers are no longer recommended for basements walls. If there's one currently, that may not be a good reason to re-install it during your reno. Much has been learned about moisture control since the 60's (mostly by doing things wrong).

Beepster

I did my first basement buildout in the Twin Cities about five years ago under the watchful eye of a building inspector. I used a 4 mil plastic sheet against the wall behind the studs. For my most recent basement buildout I put a 1" sheet of XPS against the wall behind the studs. I could have used a 2" sheet of XPS but made a judgement call. I still used the correct R value of unfaced fiberglass insulation in between the studs.

There are different things you can do, but I believe XPS sheets are becoming more accepted than the plastic sheets.

B

dshah65

Thanks everyone for the speedy response – btw, I'm in Toronto, Canada so I'll experience a variety of temperatures & humidity levels that each of the 4 seasons has to offer. If possible, I'd love some links for any further information or research.

Specifically, I'd like to learn more about the following comment:

Also, what are XPS sheets?

I really hope I don't have to pull out any studs to get a vapour barrier in. I'm going to go to my local home depot to see what guidance they can offer. I'll post it here to keep the discussion lively.

cortell

Here are two very good articles on the subject. I think Home Depot and Lowes sometimes get a bad rap , but believe me...it's the last place you want to go for advice on a complex issue like moisture control. Even if you're lucky enough to find a person experienced in construction, there is so much confusion on this topic that even an experienced contractor can give you completely wrong information. Do your research or hire a pro, but don't rely on information from a box store employee.

http://www.buildingscience.com/docum...ent-insulation

http://www.buildingscience.com/docum...ding-basements

Gary in WA

http://www.buildingscience.com/documents/reports/RR-0906_Field_Monitoring_Hygrothermal_Modeling_Baseme nt_Insulation.pdf

Gary

stadry

WHOOPS ! don't forget those apron/vest'ers had no job til they got there so IXNAY on them as a source of good advice or counsel you're better served right here