Beef up question

Hi. Here is my first post with all introduction and required stuff to post here: http://www.johnlsayers.com/phpBB2/viewtopic.php?p=79731 I want to add 2 layers of gypsum board to beef up the ceiling and the side area between the fondation and the first floor. for the ceiling, I have a lot of nails so I'll bend them and put 1/4" of floor underlayment (close cells) and my 2 layers of gypsum. My question: for the side, there was some sprayed polyurethane foam that I scraped to make it even with the framing but it's not that even and there is small cavities. Should I fill those irregularities before adding my 2 drywall layers? if yes, with what? drywall putty? look at the photos, it may be clearer... :roll: Thanks for your help. Yohann

I'd remove all the polyurethane if it's possible and replace it with proper insulation and then seal it up with the drywall. a :arrow:

Arrow, Do you mean this? (Photo 27; removing the foam, add layers of gypsum and backer rod and caulk, and then put back some rock wool) Just for anyone to know, I've been scraping for more than 20 hours and I'm just 2/3 of the job, so if I can avoid to scrape more and don't create a third leaf, I really would like to keep it like this. It's the worst job ever to remove that stuff! It's really stiff. This side of the house is the one that gets the most heavy and cold winds in winter. If I remove all of this, I'm afraid of loosing heat insulation... do the caulk joints will freeze and break at -40 celcius? it's really cold sometimes in winter here! Thanks for all the help! yohann

buchton wrote:

My question: for the side, there was some sprayed polyurethane foam that I scraped to make it even with the framing but it's not that even and there is small cavities. Should I fill those irregularities before adding my 2 drywall layers? if yes, with what? drywall putty? look at the photos, it may be clearer... :roll: Thanks for your help. Yohann

I wouldn't put drywall mud in it Buchton, myself, I wouldn't worry about it any more. Close it up like you are doing. It reads like it is just too much time for too little return.

ok, so for what I understand, those small cavities are so small and not even that they don't really matter? so no real third leaf effect? good news, if so.... I'll finally see the beginning of my project soon! :D I can put 3 layers of gypsum to compensate since it is sitting on the fondation. Yohann

Best as I can figure, either it is all mass and is simply one leaf, or it is mass/air/mass which ain't bad. I think if sound travels through one of your finished studio walls first, then hits this area, it would be considered that it traveled through 3 leaves. So maybe, in that respect, it is a 3 leaf. But in order to correct this, to make it "perfect", you would be backing up. I see it as, it should have been thought of earlier in the build so now it is what it is :)

well, if it really is that hard to remove it, just let it be and beef it up.. you're still connected to the same stud as the outer leaf so, there's really no biggie. a :arrow:

Cool! Thanks guys! I'll leave the foam trimed as it is and put 3 layers of 5/8. This way, it won't be the weakest link. just 4 hours of scraping and I'm done with it! few... what a mess! But I guess it will be worth it! Yohann