Insulating Unfinished Basement
#1
10-28-07, 07:41 PM
Insulating Unfinished Basement
Help!!! I want to insulate the unfinished portion of my basement. I live in St. Louis, MO. My basement walls are poured concrete. I have about 4 feet above grade and four feet below grade. No water leakage.
I have read the Building Science article. The foil faced foam rated for exposed use sounds great but is very hard to find and the one quote I got was about $100/ 4x8 sheet. I assume the article is referring to "Thermax" by Dow.
I'm really not interested in putting the regular foam up because then I have to drywall.
The perforated fiberglass blankets seem reasonable but I still worry about mold. But this seems to be my only option. I would insulate the top four feet, the above grade portion.
Am I stuck or is there a way out of this? My floors are freezing! I want to do the walls instead of the basement ceiling so I can take advantage of the rising heat. Also, my furnace is in the unfinished portion, and I could hold some of that waste heat in.
Thanks,
John
I have read the Building Science article. The foil faced foam rated for exposed use sounds great but is very hard to find and the one quote I got was about $100/ 4x8 sheet. I assume the article is referring to "Thermax" by Dow.
I'm really not interested in putting the regular foam up because then I have to drywall.
The perforated fiberglass blankets seem reasonable but I still worry about mold. But this seems to be my only option. I would insulate the top four feet, the above grade portion.
Am I stuck or is there a way out of this? My floors are freezing! I want to do the walls instead of the basement ceiling so I can take advantage of the rising heat. Also, my furnace is in the unfinished portion, and I could hold some of that waste heat in.
Thanks,
John
Last edited by Squire; 10-28-07 at 07:48 PM. Reason: Additional Info
#3
10-29-07, 09:17 AM
I don't want to cover the insulation because that would require framing/furring and there's no reason to do that in an unfinished area.
I really could use some more input on this. We will be very cold this winter if I can't pull something together!
I really could use some more input on this. We will be very cold this winter if I can't pull something together!
#4
10-29-07, 10:29 AM
If the area is "unfinished" why does it matter if XPS is on the walls? Why is a fiberglass blanket OK. The Dow thermax looks very similar to XPS, why is it ok and XPS not. I just don't understand your concerns.
If I could redo my basement, I would use spray foam on the rim joist to greatly improve the insulation properties.
If I could redo my basement, I would use spray foam on the rim joist to greatly improve the insulation properties.
#5
10-29-07, 10:43 AM
Member
Insulating Unfinished Basement
chris -
Any flammable insulation must be protected from flames for life and safety. Ofter foils coating will qualify.
Fiberglass gets worthless as it accumulates dirt and dust, and any moisture can be held which will destroy the insulating properties. Fiberglass will not dry out while in place since the air movement in not permitted by the structure.
Spray foam is good for rim joists and can be a great insulator, but it must be controlled for any performance guarantees and it must be used properly with regard to moisture conditions.
Basement walls do not need and should not have the same degree of insulation as above grade walls because of the different temperature differentials and moisture conditions.
Dick
Any flammable insulation must be protected from flames for life and safety. Ofter foils coating will qualify.
Fiberglass gets worthless as it accumulates dirt and dust, and any moisture can be held which will destroy the insulating properties. Fiberglass will not dry out while in place since the air movement in not permitted by the structure.
Spray foam is good for rim joists and can be a great insulator, but it must be controlled for any performance guarantees and it must be used properly with regard to moisture conditions.
Basement walls do not need and should not have the same degree of insulation as above grade walls because of the different temperature differentials and moisture conditions.
Dick
