I'm insulating an attic on a house I'm building. I need R49 insulation and when looking at fiberglass batts its going to cost like $6,000.http://ift.tt/2wlfVBl have 17 cavities between trusses with a 20' span meaning I would need 5 of those for each cavity times 17 resulting in 85 bags at $72 each?This seems ridiculous.I can buy rigid foam R10 insulation boards for $30 each and stack them 5 high to get R50 and that only comes to 22 boards x 5 layers = 110 boards * $30 or 3,300.I feel like I must be missing something here. Why are fiberglass batts costing twice as much as rigid foam insulation sheets?If I use the rigid foam boards its only 10" total compared to 14-16" with fiberglass batts so I save some headspace in the attic too.This is kind of a unique question I'm sure but any help would be appreciated. I wasn't expecting to spend $3,000+ to insulate the attic. I can't use blown in insulation as its not allowed per code with my roof pitch in this state and its also too thick (16.5"). via /r/DIY http://ift.tt/2vmA5Gk
