Hello,
I’m going to be finishing a basement and could use a few questions answered. It is about three years old , poured walls, 8″ thick. Ten ft. high…..Two ft is above grade. I’ve been set up and working in there for about a year through all kind of weather and no leaks or dampness at all. The rest of the home is done and now I’m ready to stud up and drywall the basement.
The outside was insulated sealed and frenched drained. Radiant heat in poured floor.
My questions…..Do I need to put in a vapor barrier and what kind ??? Steel studs or wood???? Any special techniques or tips would be great.
All the rest of the work I’ve done in the home has been top notch…I don’t want to screw up the basement. Its going to be used as a TV room/ 2nd living room.
Any help would be great ….Thanks guys
“Man is a tool-using animal…
Without tools he is nothing,
with tools he is all.”
~Robert Browning~
Edited 8/24/2009 5:17 pm ET by mjcwoodworks
Edited 8/24/2009 5:31 pm ET by mjcwoodworks
Replies
We've almost declared Nuke to be our in-house basement expert...
Pete, funny.
I did not use a vapor barrier. I had years of reading on FHB and even the mazazine authors countered earlier articles on the use of a vapor barrier. Some questions need to be ask before entertaining and debating the vapor barrier question:
Will you be installing an AC, heatpubp, etc. for the basement?
What is the relative humidity like in Winter and Summer months?
Have you performed multiple sealing tests whereby you tape plastic squares over the poured concrete walls and floor, leave them for a couple of weeks, and peels back to see if moisture is collecting underneath?
What kind of rainfall, and what kind of grade is your basement built into?
For instance, if you lived in Death Valley I would not expect much in terms of moisture coming from the earth trying to pass through the poured concrete to get into the basement air voilume. A vapor barrier would only benefit in keeping moisture in the living space from passing to the poured concrete wall.
On the other hand, living in Portland Oregon where the rainfall is heavy year round and with a high relative humidity could mean a substantial amount of moisture from the earth pushing into the concrete and needing to be handled. Without testing how can you ever feel confident you will not have a moisture, and hence mold, condition in the future?
Haven grown up as a child in a poor environment where insulation and moisture control were terrible, and then growing up in a tract home of poor construction and afford water infiltration, mold was identified in terms of root cause, and as such made me think multiple times over for how to handle the basement.
And while Georgia is in the middle of the road in terms of rainfall and relative humidity, I spent the time (five years) and conduted multiple seal tests because of my paranoid concerns over this issue.
Caveat: I am not a builder or trademen. I work in a cube for atelecommunications company and relied heavily on people like breaktimers to learn from--even though opinion can be opposition. In the end, I also learned that a DIY can be an endless endeavor and I, personally, chose to finally hire it out.
I've finished a few basements including my own, and although I'm hardly a pro, I can offer my observations. In my experience, the number one thing to get right with a basement is air handling. The rest is just wood and sheetrock and things can only go so wrong. Basements tend to be areas that attract temperature differentials and humidity from everything from dryers to pinhole plumbing leaks. In extrement cases, this leads to condensation and water damage, but more often just excess humidity / mildew. Unless you have can condition the air, you are destined for some unpleasantness in the future. If I could do it again, I would spend the money on an HVAC consultation before the work rather than after.
After a ton of research (much of it done here) I went with building science corp's method:
From outside-in:
- EPS board insulation, taped (I did 3" for r-10 per local code)
- steel studs (lighter, straighter, mold proof) with 1/8" XPS underneath floor plate for thermal break
- paperless sheetrock (densarmor)
The basic argument is that it's a basement. Water is going to get in somehow. The foam acts as a vapor retarder, but still allows for drying one way or the other in worse case scenarios.
Ideally, you'd use spray foam on the walls (but that's pricey).