Final Advice before I start please.

Mijotter · 11-14-2012, 03:11 AM

Ok, So I have been browsing and gathering knowledge for quite some time now and always, it never fails, someone suggests something that kind of makes sense that screws everything up lol. So instead of doing more research and reading, i'd love to hear from everyone personally concerning my specific issues and questions. Thank you in advance.
btw - I do not have much moisture problems at all. Very dry basement.

1. I'm convinced that the best way to insulate my Basement masonary walls IN the basement is XPS rigid foam board on the masonry, stud wall over that, drywall over that. My first questions is, What's the best wat to apply the XPS to the wall? Glue? Screws(kind of defeats the purpose), or not at all and let the studs hold it up?

2. Is 1" or 2" XPS Rigid R-10 better? I've read that 2" is too thick to allow proper ventilation but i've also read that 2" would allow me NOT to use batts.

3. Do you recommend batts between the studs for this current setup and if so, unfaced? or which side should the face be...um...facing lol. ie are batts really necessary or will it constrict the breathing too much?

4. Should i take the XPS all the way to the concrete floor and ceiling joists?

5. Is XPS board ok to use in the rim joists or a combo of XPS and batt preferred?

Windows on Wash · 11-14-2012, 10:01 AM

Quote:

Originally Posted by Mijotter

Ok, So I have been browsing and gathering knowledge for quite some time now and always, it never fails, someone suggests something that kind of makes sense that screws everything up lol. So instead of doing more research and reading, i'd love to hear from everyone personally concerning my specific issues and questions. Thank you in advance.
btw - I do not have much moisture problems at all. Very dry basement.

1. I'm convinced that the best way to insulate my Basement masonary walls IN the basement is XPS rigid foam board on the masonry, stud wall over that, drywall over that. My first questions is, What's the best wat to apply the XPS to the wall? Glue? Screws(kind of defeats the purpose), or not at all and let the studs hold it up?

Foam compliant glue works well and if you are studding out the wall shortly thereafter, make it tight to the foam and use the studs to brace/compress it tight to the wall. Ship it out if the wall is out of square so the stud is applying positive pressure to the foam.

2. Is 1" or 2" XPS Rigid R-10 better? I've read that 2" is too thick to allow proper ventilation but i've also read that 2" would allow me NOT to use batts.

There is no ventilation here. 2" would be better.

3. Do you recommend batts between the studs for this current setup and if so, unfaced? or which side should the face be...um...facing lol. ie are batts really necessary or will it constrict the breathing too much?

Unfaced.

4. Should i take the XPS all the way to the concrete floor and ceiling joists?

You can, but not before you seal up the ribbon board and insulate it.

5. Is XPS board ok to use in the rim joists or a combo of XPS and batt preferred?

Combo works well.

See above.

Mijotter · 11-14-2012, 03:47 PM

Sorry what is the ribbon board? Also should i seal the top and bottom of the xps and if so how? Thanks.

Lifeguardr · 11-14-2012, 04:27 PM

I just finished my basement family room and have really been pleased with how it went.
1. I glued the 2X8x2 styrofoam shiplap panels to the bare concrete wall with PL300 and tuck taped the seams.
2. Use the 2" for sure.
3. I used R14 Roxul batts between the studs. It makes for an R24 wall.
4. Use the 8 foot panels all the way up.
5. Cut the styrofoam with a drywall saw to size and put them between the joist ends. Then use the expanding foam around to seal it; then cut Roxul to fit. It makes for an absolutely airtight fit and is insulated as well as the wall.
Hope it goes well!

Mijotter · 11-14-2012, 07:56 PM

That's awesome. Do you by chance have any pictures showing your progress. Did you seal the top and bottom of the foam that was against the concrete wall?

Lifeguardr · 11-14-2012, 08:36 PM

You don't need to seal the top and bottom if you run a nice thick bead of the PL 300 across the top and bottom and make sure it grabs the wall. If there is a gap, you can always use expanding foam to fill it. Sorry, no pictures of this part of my project. I used the big tubes of PL and went through them pretty quickly. You may want to be sure you have enough.