Basement insulation

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wg_bent

Minister of Fire
Hearth Supporter
Nov 19, 2005
2,248
Poughkeepsie, NY
Well, it's been a long week of simply taking out carpet and putting in laminate flooring in the basement.

When I pulled the carpet up, I noticed that the baseboard was rotted. Yup, dirt, falling apart, rotted. (this is bad!!) Off comes the sheet rock. hmm, cinderblock foundation, with 1/2" furring strips nailed to it, then plastic sheeting, then sheetrock. Very wet inside and stunk like rotted wood (the furring strips). next wall...2x4 wall, no insulation, just same plastic, same rotted bottom plate.

:sick: >:(

Lots of thinking, finally looked on the web and found this link:

(broken link removed)

I'm down to the cinderblock walls, and am now putting up 2" insul-pink (r10), followed by 2x4 walls with non-faced bats for a total of R23 in the basement. I think that should be enough.

If anyone has any ideas, on me doing this wrong let me know.

The basement is 15x20 plus an 8x10 office. The ultimate plan is to put a small wood stove down there. Maybe a morso 1410, VC 3cb, Lopi Answer, Osburn 1500, or similar sized stove.

I want to see the effect of insulating first before adding a huge amount of heat I don't need.

I usually like these kinds of projects, but this one really has me bummed. Just a PITA. Not creative, not fun, just grunt work.

BUT, I do like the fact that the insulation will make the house a lot more comfortable, and warm.

p.s. sorry for whining
 
Hello Warren,

Thanks for posting the article..it will certainly help us....we have a hearthstone mansfield in the finished section of the basement and it basically heats most of the house in Quebec...There is insulation on the exterior of the foundation wall. Believe it is approximately an inch maybe more..Don't know what is on the inside...This year we got a dehumidfier and it has made a big difference for the summer especially with the monsoon year so far..... In the winter the mansfield takes care of the humidity....Have been meaning to find out more as the misses wants to put a bath tub in the downstairs bathroom..kinda wondering what we will find...understand you being bummed... Our stove location is closer to the foundation wall on one side..THe grass near the wall can usually be seen on the exterior and we are in a snow belt..pretty green also...Others up here tell me that is normal...Am anxious to hear the outcome after the winter...matt
 
When I do basement playrooms I cote the walls with ULGI concerte water sealant I apply two coats with 6" wallpaper paste type brush The plastic does as you described traps moisture then wicks off rots drywall and the baseboards Before insulating I think it wise to address your walls and watyer proof them I also seal the concrete floor with silicone water seal product.. the
the pink poly filled insulation good but will not prevent moisture. The key is moisture prevention first
 
Elk has it right. First, stop the moisture for sure. Also check outside. Are there any downspouts or clogged gutters that are letting water spill off the roof, close to the house?

For the basement walls, go with rigid insulation. In a hollow wall cavity there can be a large temp differential between the concrete and the drywall. This can cause condensation and mold, so insulate carefully and do it by the book. Here is a good resource for basement insulation questions:

(broken link removed to http://www.buildingscience.com/resources/basements.htm)
 
The idea is that moisture that gets on the wall can dry by migrating through the foam and then out through the unfaced fiberglass insulation. Are they recommending 2" now for the foam? It might seem a bit thick to still allow moisture to travel through it. The main job of that isulation is to prevent warm moist air from condensing on the surface, I would think.
 
There should be no moisture. That's why the first step is treating the wall and absolutely making sure there is no moisture coming in. If the insulation is well installed and doing its job, there will be no condensation.
 
I forgot to mention this before but I take another precaution when applying drywall that comes in contact with cement.
One method is to place 3/4" blocks on the floor and leaving a space so that drywall does not make direct contact with the cement floor. The other method is usinga galvanized J channel on the botton of the drywall sheets, again separating drywall to concrete froor contact
 
elkimmeg said:
I forgot to mention this before but I take another precaution when applying drywall that comes in contact with cement.
One method is to place 3/4" blocks on the floor and leaving a space so that drywall does not make direct contact with the cement floor. The other method is usinga galvanized J channel on the botton of the drywall sheets, again separating drywall to concrete froor contact

Right. I'm planning on doing exactly that, plus use the foam mouldings. I'll also put a layer of silplate insulation under the wall.
 
And while you are in there and if it hasn't already been done don't forget to insulate your sills. Thats one of those major energy wasters people often forget about. Heres another interesting one I just found. For windows you don't always need to see out of use bubble wrap cut to size and simply stuck on using water. I imagine a putty or drywall knife makes it go on easier. It will raise single pain R value from a 1 to around 2 and an insulated modern one by about 40%. The article says it looks about like stained glass and the pics seem to bear it out. They say not to buy it from a UPS or Post Office Store but rather from someplace that sells rolls like a freight repackager ect.
Here is the article from one of the Build It Solar Archives. You will note that it shows the biggest energy wasters are the sills, wall tops where they join the roof at the atic ect. Its a good read along with all their other free info.........................Here is the link I forgot to install, woops http://builditsolar.com/TopTen/tenoneyearpb.htm
 
Warren, if radon mitigation is in your future now may be the time to do it before re-remodeling.
 
velvetfoot said:
Warren, if radon mitigation is in your future now may be the time to do it before re-remodeling.

Good suggestion. When we bought the house 3.5 years ago we had it checked and it was quite low. :-) :-) :-)
 
Driz said:
And while you are in there and if it hasn't already been done don't forget to insulate your sills. Thats one of those major energy wasters people often forget about. Heres another interesting one I just found. For windows you don't always need to see out of use bubble wrap cut to size and simply stuck on using water. I imagine a putty or drywall knife makes it go on easier. It will raise single pain R value from a 1 to around 2 and an insulated modern one by about 40%. The article says it looks about like stained glass and the pics seem to bear it out. They say not to buy it from a UPS or Post Office Store but rather from someplace that sells rolls like a freight repackager ect.
Here is the article from one of the Build It Solar Archives. You will note that it shows the biggest energy wasters are the sills, wall tops where they join the roof at the atic ect. Its a good read along with all their other free info.........................Here is the link I forgot to install, woops http://builditsolar.com/TopTen/tenoneyearpb.htm

Another good one. I'm pumping Greatstuff into all remaining spaces where the Insulpink wouldn't fit. The one bummer is the one basement window is a single pane of glass. I'll probably put in some sort of additional storm window for the winter plus a custom fit shutter.

That actually brings up a point I'll post in another thread on insulated shutter's
 
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