I am in the process of finishing my basesment and I was wondering if
insulating a basement helps much. My house is about a year old and it has a
poured foundation. My basement seems to stay pretty warm even though it is
getting down to 0 degrees overnight. My walls seem to stay pretty warm also.
Also, I was wondering if a vapor barrier is needed between the wood studs
and the basement wall. Thanks for any help given.
You should have insulation along the rim joist (at least 6"), and you should
insulate from the top of the foundation down to a couple of feet below
grade. This will in fact keep your basement warmer. I used insulation
enclosed in plastic (sort of blankets), and I put a studwall around part of
the basement. The vapor barrier should face the heated space, but if your
foundation leaks it is going to present problems no matter what. In fact, a
leaky foundation (or the possibility thereof) is a real argument for not
doing anything to cover basement walls. The stuff in blankets is pretty
good, water won't penetrate the insulation at least, but if the wall leaks
at all you are going to get mold, which would be worse with regular
Insulation is always worth the effort. My current home had no insulation
over the garage. I put r-19 batts in. Made a difference with the heat.
Check into the blue board at the home centers. Or the foil backed should be
pretty impervious to water, your dry wall will not. So if you have leaks fix
them first then insulate, wall board and paint. It will look just fabulous
when your done
Along that line, I see in this weekend's Menard's ad, a drywall product
designed for basements. It claims to be impregnated with fibreglass, etc
and is supposed to handle moisture below grade better.
First..you should insulate. Although heat losses are figured to only
about 4 feet below grade, most cellars are barely able to get this far
once the grading on the yard is done.
Second....yes, you might need a vapor barrier. Try the old trick of
testing you wall for moisture content. Take a sheet of aluminum foil
and duct tape it to a clean spot on the wall overnight. Check it the
next day to see if any moisture has developed under the foil. Do this
with your floor too if you intend to put something over it. You would
need a vapor barrier if either shows moisture but I'd be inclined to put
it down on the floor anyway. You never know. As for the walls, you can
ease your worried by using foam insulation. Water has less of an affect
on this than on fiber glass.
Hope this helps.
Ummm... First you should ensure that your basement doesn't leak. If
it does, fix that - _then_ insulate.
This is good advice. If you do a test and it just happens to be an unusually
dry period of time, you won't know that your result is valid. After a period
with lots of rain etc, may result in dampness permeating the basement anyway.
Personally, I'd never put wood down on a concrete basement surface without
a waterproof layer in between. Low cost insurance.
I'd also insulate right to the floor. While the temperature of the soil
below the frost line is not extremely low, it is still below a comfortable
temperature for the basement and will absorb heat. It's insulation that
is less efficient than that working against cold air, but it's also a
marginal cost compared to the rest of the work of finishing a basement.
We built a house next door to our original house. House 1 (original) had a
cold basement in the winter. You could go downstairs for quite a while if
you wore a sweater. House 2 has 2 inches of pink Dow board insulation
around the outside. You can be comfortable downstairs in a short sleeved
shirt. If I ever build again I will insulate around the outside again!
Vapor barrier is supposed to go on the heated side of a wall, therefore the
vapor barrier should be between the insulation and the drywall. You are
using moisture resistant drywall, correct?
Remove .spamnot to respond by email
I already did the moisture test and dont seem to get any moisture buildup on
the floor and walls.If I were to find out that my walls have moisture, does
that mean I need a vapor barrier on both sides of insulation? I will go
with the insulating and vapor barrier between the instulation and drywall. I
just wanted to make sure it made a big difference before I do. Someone told
me a while back that the ground acts as insulation so it wasnt really
required. And my basement does stay pretty warm, even in the unfinished
state. Thanks for the help
Theoretically, the concrete walls below grade stay at 55 degrees
Code for insulation here (Calgary, Alberta where it is minus 30
celsius this morning) is R 20 above grade, R-12 below grade.
No to vapour barrier on both sides of the insulation. Code here is
for moisture barrier from floor up to four feet or grade level,
whichever is least. Significant moisture problems are repaired from
If you have forced air heating with registers and cold air return at
ceiling level, drop the cold air return to floor level. That's the
cheapest, fastest way to improve heat circulation .. it makes a
HomeOwnersHub.com is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here.
All logos and trade names are the property of their respective owners.