ridged insulation in converted attic.
nash
| Posted in Energy, Heating & Insulation on
Hello, I am finishing converted my attic in my 90yr old house into livable space.
I’m deciding on whch insulation to use. I would like to get most insulation as possible. I have 2×8 rafters and 2×6 walls. I do not want to use spray foam.
Does it make sense to use ridged insulation cut to go between rafters and wall studs ? If so what type would you suggest. Also what method of installation, should I “great stuff” the seams or use foil tape or a different method ?
Should I use a combination of fiberglass and ridged ? would there be a problems with the vapor barrior and condesation between the two materials.
I also have eave and ridge vents
thanks in advance
Replies
Greetings nash,
That topic has been discussed much in previous threads and your concerns are warranted.
In the event you fail to receive the information you requested you may be able to find it in the archive listing of old threads on Breaktime.
If you scroll up in the upper left corner of your screen there is an advanced search function that will take you to a page of instructions directing you to previous threads dealing with whatever you type in the search bar.
If you type in 'roof venting', 'foamboard insulation' or other keywords of the subject matter you'll get a supply of data from those old threads.
Cheers
Nash,
Depends on how much insulation you want? 2x8's dont give you a lot of insulation if you just use fiberglass because you have to leave an air channel for air flow against the roof sheathing. The way I would do it is use 2x6 roll insualtion then over the rafters use rigid insulation (1/2 or 1 whatever you want) then furing strips running across the rafter (perpendicular) and attach you finished ceiling to that. You will have a well vented, highly insulated ceiling. Do a similiar thing on the walls, a bit more work but you will see great savings in heating and cooling depending on where you live? I have done this with great success.