Basement Insulation

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Well, I got some furring strips to go along with the 10 Foamular tongue in groove 2" boards.
Found a big tube of the pl300. Also, harder to find were 4" tap cons which I figure is the size I need.
I'm still not clear on how to glue/seal the foam to the wall as well as seal to each other.
The www.buildingscience.com website is not that clear.
Would there be a bead all around the edges of each piece of foam to glue and seal to the concrete, plus some in the field?
Then also some glue on the tongue in grove section for sealing?
That's a lot of glue.....
 
Don't over-think it; the glue just keeps the boards in place until you get the furring strips in. Then if you want, you can seal along the perimeter to kill any chance of air currents setting up. But I think even that is a pretty subtle detail compared to the benefits of just getting the insulation up.
 
Thanks. They're pretty seal crazy on that website, but the Dow site (Corning has nothing specific) just seems to say to slap it up there with furring strips.
 
I agree with precaud. In our (tall) crawlspace I just used Liquid Nails LNP-901 heavy duty glue (approved for foamboard). Bought a case of the large tubes at HD and put a generous amount on each sheet. (I think we got about 2.5 - 4x8 sheets per large tube). Let it fire off for a minute, then pressed in place. Wedged a couple 2x4 T sticks to hold it for about 5 minutes while we got the next one prepped. That's all, no tap cons, no furring strips. It's been up for 3 years now and is very solid. That stuff is not coming down.

Does it work? The coldest temp we've seen in the crawlspace was 60, with it 20 degrees outside. Normally in winter it sits at about 63 degrees.
 
Yeah, I don't want to overthink it. But, it's not that clear to me how to brace it when applied on the interior. I'm thinking I'll use the furring strips - don't know about the time factor. Again, not overthinking: key.
 
Sorry, I didn't mean that in the derogatory sense. Maybe another way to put it is: if you're going to put up drywall or another finish layer over it, then you need the furring strips. Otherwise, perhaps not, and BG's method would work fine.
 
My suggestion is not for a finished space. If you are putting up drywall then put up the firring strips or 2x3s first. What surprised me was how quickly the glue fired off and started holding. All you need is a very temporary solution. Once it's bonded to the concrete, you have to chisel it off. It cures fully in about a week, but is holding well after about 5-10 minutes. The trick is to let it dry for one minute before putting it up.
 
I didn't take it in any bad way. On the one hand I don't want to go totally crazy thinking about it, but I thought I might have had to rethink my whole approach since two big home stores in my area, including HD, did not have long enough tap cons for my plan. It's good as well to have a feel for how quick the adhesive sets.
 
Well, I started. I started to put up some panels, putting spots of adhesive on the back. It's only temporary anyway, until the furring strips go up. I smeared some adhesive to act as a sealant between an 8 inch section I had to add to the bottom of each panel. I started smearing it on the front of the vertical tongue and groove areas, but stopped after a while because it was messy-that pl300 adhesive doesn't disnpense that smoothly. The concrete wall, which might look smooth from a distance, is far from it. Things I've noticed so far:

-There are a fair amount of things next to the wall that don't move that easily, like the oil tank, boiler pumps and manifold, circuit breaker panel, domestic hot water tank, sewer pipe, etc., that chances are won't get insulated.
-I'm don't know what to do about the insulation around the window and door. Extend the frame somehow? Flashing?
-It cuts nice with a table saw-especially those 8" sections
-A long utility knife worked pretty good for the window opening, but not as smooth as the table saw.
-It will be tedious to remove the existing wire located on furring strips on the concrete walls to the furring strips that will brace the inulation boards
-Then there will be the external electrical boxes that will have to be replaced with low profile models.
Anyway, a lot of liitle things and places where it looks like it'll be hard if not impossible to install the boards and drywall.
Just some obsevations so far...
 
I did this type of renovation a couple years ago and it was very worthwhile. I used 2" foam (blue or pink not the foil faced as that will wick moisture) then a stud wall with non-faced fiberglass. This is what buildingscience site recommended, and it's working really well. I sealed the cinderblocks first with drylock, glued the foam to it then did the stud wall. I finished off with sheetrock.

Warren
 
Thanks. I'm going to see how the furring strips work.
Next questions are lighting (I'm not a big fan of the recessed pots) and floor.
 
I'm no big fan of the recessed pots either, but... my kitchen has them, and I've got regular 15W curly-Q CFLs in them. With four of the six on (I keep two screwed in halfway) the kitchen is lit about as well as the six incandescent spotlights that came with the house, with none of the heat. Just having the incandescents on were enough to heat the kitchen without the heater. The CFL spotlight bulbs don't work well, and they take time to warm up when they are cold. When cold they put out little light, takes about 5 minutes to warm up. This was only nice at 5AM going to turn on the coffee pot, but otherwise would have to turn on the lights, then come back 5 minutes later if I needed in the kitchen. This is not a problem with the curly-Q ones, they light up instantly.

I'm really hoping that by the time I'm actually building the house, that LED technology will be viable for whole-house lighting instead of spotlighting like it is now.

Also, stay away from ceiling fans with light kits that point the bulbs straight up. They have a strobing effect when the fan is on.
 
I got a couple of led mini spots, mostly for the little woman who like to keep them on. They really don't put out that much light and were, like, 25 bucks each.
I'm okay with the cf spots in the kitchen, though they do take a while to warm up. I just don't think that the recessed lights in general put out much light. I'm not planning on putting in more light circuits so I'm going to stick with 6 flourescent fixtures in the 1000 ft2 basement, win or lose I guess.
 
We are getting off the topic here...

But for our business I ordered 2 LED exterior broadcast lights. They are 50W in lieu of 400W. We have them on 60-80 hours a week. They are an extra $100 ($250 instead of $150), but by my math I paid the extra $100 for them in 42 weeks at $.10/KW. They were new lights, I needed them and didn't have them before, otherwise you need to do the full $250 cost on the payback allowance. Even throwing in $60 for install on a replacement job, that still pays for itself in 130 weeks.
 
Velvetfoot, if you have a curly bulb, stick one in the pot and I think you'll be surprised at how well it works. I was, tried it when a bulb burned out and all I had left was the curly bulb. Was just going to be temporary until I could get another spot, but when I saw how well it worked I just replaced all of them with the curly bulbs. And, found I only needed 3 of the 6, when with the CF spots I needed all 6. Currently have 4 running though.

mbcijim is correct though, to go further on this we should probably start a new thread, if anyone is interested in discussing lighting.
 
Thanks. I never tried the curlies in the pots, figuring the curlies-in-spot bulb would be better. It's way more expensive though.
I still don't think 6 will kick off enough lumens for a 1000 ft2 basement.
Of course, there's the dropped ceiling style to discuss: I heard www.ceilinglink.com was good and cheaper than HD's, but still not cheap.
Then the floor: 1" xps + what? I'd like an engineered wood floor on top, but not sure if that's considered an adequate fire retardant.
Everything is so expensive: the 2x8 corning formulate 250 xps from HD was something like 13.90/sheet.
Doing math for a 1000' square floor, you get big numbers (for me) for the eng. wood floor.

This could be spun off into a basement finishing thread...
 
Of course, then there's the treatment around the increased depth of the doors and windows for the wall insulation, and then the floor....
 
Starting to look at surface mount flourescent fixtures. I'm thinking 2 bulb T8. The lowest temp bulb they have in HD appears to be 3500K. The curly Qs in the house are 2700K.
 
Most walls covered with foam now.
Put Tyvek tape on one wall and started to drill holes for the firring strips.
The Black and Decker hammer drill crapped out after one hole! I bought it new last year and this was all the work it had seen. One hole in concrete! I couldn't believe it.
I took it apart and there was a broken gear and loose parts. What a piece of crap.
I got a Harbor Freight rotary hammer drill for 70 bucks. We'll see how that works out.
 
We used to Call B+D tools Black and Decker Pecker Wrecker.
One thing you don't cheap out on is tools. You will always regret it.

Unless they are for one use only. Then I buy Chen-Shek tooling.
 
I'm looking at that hammer drill now, and wow, it looks pretty substantial! Tomorrow, I'll try to drill some holes if can figure out how it works.
 
You just put the drill in hammer mode (some setting) and drill. Make sure you have the right bit for the drilling.
The hammer drill just just vibrates back and forth.
It does take a bit of force to drill depending on the size of the bit you are using.

Wear a dust mask and good luck.
 
I just put about 7 straps at 5 screws each. That rotary drill is fantastic! Goes through the concrete like butter! I didn't realize that I needed a special bit. Thankfully the hardware store had one: 10 bucks! Not much force required except to hold it up in the air (not that light!).
 
I have a 1120 sq/ft basement and was losing heat like crazy. It took 2-3 hours of the stove running to get the warmth to come upstairs.

I insulated with the 1 inch pink poly, just glued a few sections at a time on the wall, amazing difference. Some areas I do not have the wall studs against the poly and it is stuck on there good. In fact, while looking for a water leak, I tried pulling a section off...no way. That glue is VERY srong. the p[oly broke off in tiny pieces.

So when I finally do finish, I'm just going to put unfaced r11 in the walls. There is no problem with moisture on the walls at all when using this stuff. I used to have a musty smelling basemnt, not anymore, and my floors are still exposed.

It is so worth it and anything more than using the correct glue is over kill when fastening the one inch. By the looks of it, it would be overkill on the two inch also.
 
Except for the fact that there're words all over the foam that says it has be covered with .5 " of sheetrock or equal.
Good to hear that it's not as musty even with the floor the same.
 
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