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Old 04-06-2010, 03:09 PM   #182
Ran D. St. Clair
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Join Date: Apr 2009
Posts: 212
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The Ceiling Is Closing In On Me…

Yes, I know, I wasn’t funny the first time… Believe it or not, I am still putting R-Max in the ceiling. This has turned into a very slow and tedious task. The walls were a little slow, what with cutting the insulation to fit around all the conduit, but the ceiling is really slow. There is room for 5 each 1 inch layers of R-Max between the rafters and it takes a very long time to wedge all of those layers up there. I can literally spend all day getting just 2 bays done, and an evening after work doesn’t even complete one bay (space between two rafters). I can’t say that I am enjoying this much, so I would suggest you go talk to Geofkay about spray foam. It might not be cheaper (or perhaps it is, I really don’t know) but it has got to be faster. I would think that even two layers of fiberglass bats would be way faster, and given that I have 4 1/2 to 5 1/2 inches of insulation space in the ceiling it would probably be more than adequate. At this point I am almost done so I guess I will just stay the course. I console myself with reminders that I will have one very well insulated living space when I am done. It is already very comfortable for working on a mild winter day with nothing but the heat from my shop light.

I did end up using the injectable spray foam in a few places. I had a few small areas where I wanted to fill the space, but didn’t have much access to put the rigid foam in. I ended up wedging in some of the 1 inch thick R-Max to enclose the space, then injecting the foam in on top of it. Actually I had a whole plan, which went down hill really fast when it came time to implement. I figured I would put in about a 6 inch section of R-Max, then inject the foam in on top of it, then another 6 inch section, more foam. The plan worked great until the pressure of the expanding foam started pushing the R-Max out of place, at which point it would fall on the floor along with a big pile of wet sticky foam. At one point I was running around like a one armed paper hanger pushing the R-Max panels back into place until the foam started to act like glue and locked them into position. Needless to say, when I was done there was half as much foam on the floor as up in the ceiling. Fortunately it cleans up easily if you let it dry and harden first. Cleaning it up while wet and sticky is next to impossible.

When using the injectable foam, you have to hold the can upside down. In my case, I was injecting up into the ceiling so the little tube that comes with the can was no where near long enough. Fortunately I have some plastic tubing that is used for model airplane control linkages, so I used that. It was just the right size to press into the tube that comes with the can. It worked great. I was able to insert the tube all the way to the back of the space being filled, and then let the foam expand towards me insuring that the space was completely filled. That is, it worked great until the pressure of the foam pushed the long tube out of the short tube. When it came apart I had foam everywhere, my face, my shirt, my glasses. The can warns about not getting it on your skin, and advises wearing gloves and safety glasses, they didn’t say anything about a full body condom though. Fortunately it wasn’t that hard to get it off my face. I was so busy dealing with the rest of the mess I didn’t realize that it was all over my face until it had pretty much dried. At that point I could just pick off the rigid globs and I hardly lost any skin at all. Hey, I figure some people pay good money for a nice facial peel.

Alls well that ends well, but what I don’t know is how well the foam really filled up inside those hidden bays. I see some of the larger globs of foam that ended up on the floor tended to develop big empty bubbles inside. The whole idea of insulation is to break up the air spaces into tiny air spaces so convection loops can’t form, or at least if they do form they are really tiny. I have no idea how it really turned out, and I am not going to rip it all apart to find out. I do suspect that it will be days or even weeks before all that foam completely dries. Hopefully the fine bubble structure will last until it does. If not, oh well, it is not really a significant percentage of the overall insulated surface anyway.

To be continued….
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