I am finishing the basement in my 90yr old house. The floor is concrete, in good shape (in fact, it is stamped into a square pattern with the squares about 14″ x 14″. There was carpeting with a pad down when I bought the house 6 yrs ago. Concrete thickness is about 2″.
Question: is it a good idea to put a sheet of 6 mil plastic down on the concrete before installing a new pad/carpet. I always use a treated bottom plate when framing walls in a basement, so wouldn’t migrating moisture (even if the basement is dry) potentially cause a problem w/o a vapor barrrier, too?
Thanks for your input.
Replies
Greetings do,
This post, in response to your question, will bump the thread through the 'recent discussion' listing again.
Perhaps it will catch someones attention that can help you with advice.
Cheers
'Nemo me impune lacesset'
No one will provoke me with impunity
I think the poly is a good idea. A concrete slab is like a giant sponge. It wants to dry to the inside of the structure.
bump
'Nemo me impune lacesset'
No one will provoke me with impunity
No. If the slab is always dry you don't NEED the plastic. If the slab is ever wet you don't WANT the plastic.
Yes it would keep the water away from the carpet. It would also NOT allow the water to evaporate to the inside and you would have constant water and mold under the poly.
The place to put the barrier is outside the slab (under). Once the camel is in the tent...
DG/Builder
Hello:
I have the same "challenge" in my own basement and for what to do I've been mulling it over in my head for over a year and still haven't come up with anything I would jump at doing. I thought about poly, but dgbldr's post has crossed that idea off my list. Mapei makes a couple of products that I haven't tried, but it's a well respected manufacturer, so I'd tend to believe their claims. Another problem is I believe the stuff is a bit pricey and when it comes to my own home, budget is a huge factor (lottery tickets never seem to hit ;-). Camel's nose got under my tent before 1890 or so; I run a dehumidifier for now.
Anyway, you might want to take a look at the Mapei Planiseal MRB and the Planiseal 88.
http://www.mapei.com/MapeiAmericas/en/products_line2.htm
http://www.mapei.it/referenze/Multimedia/Planiseal88_TD_EA.pdf
Best of luck.
Seeking perfection in an imperfect world is a fool's errand. Making something look perfect is a whole 'nother story . . . .
I'd always hesitate to carpet a basement floor, unless you're going to actively dehumidfy the place in the summer. What happens is that humid air gets down into the carpet, which is kept cool by the slab. When this occurs, you can get condensation, or at the least an increase in the relative humidity. Dust mites need a relative humidity of something like 40% or higher to thrive, and carpet is perfect for them.
What follows is conjecture, but I suspect it's correct. You should also know that I'm not particularly prone to allergic reactions from anything. While we were building this house, we lived in a rental with a damp basement. The humidity was always high, but the second summer we were there, we hit a really humid stretch. There came a night when I couldn't sleep in the house for sneezing. I don't think it was mold, because no blooms were visible. I thinkwe just hit the perfect conditions for dust mites, and the population exploded. A thorough vacuuming helped, but the problem didn't fully abate until the humidity declined.
So, I don't like carpet and humidity. Well, either one alone, to be truthful. But the combination is particularly nasty.
Andy
"Never try to teach a pig to sing. It wastes your time and annoys the pig." Robert A. Heinlein
"Get off your dead #### and on your dying feet." Mom
Homasote makes a product for use under carpet on concrete floors. Called warm floor or something like that.I have no idea what it's moisture vapor characteristics are.