Rigid foam insulation between rafters
I am wondering if anyone has installed rigid foam insulation in between rafters? I have a 100+ year old home in Grand Rapids MI with a full walk up attic, with two by six rafters. In order to get the best R value and to be able to do this myself I figure the rigid foam boards would work best. I was thinking of cutting them to fit and using the expanding foam cans to fill in any gaps. I have found a place that I can get reclaimed/recycled foam boards by the pallet at a significantly reduced price. I would leave some room for venting and use blown in cellulose in the knee walls and ceiling to get the needed R value. I have been researching this for awhile and have not Found any posts or info on this.
Re: Rigid foam insulation between rafters
I am considering the same thing. My house is not as old (mine is 1929 built) but has 26" on center rafters. I have been told not to use spray foam on the roof since it conceals any leaks and would be a problem unknown until it was too late. With the roof constructed from 2X6 and the attic floor joists also from 2X6 I think the rigid foam may be my only choice for decent R value without the problems I was warned about with spray foam. Although I dont live in as cold a climate as Michigan, Queens NY can get cold enough and the wind off the Atlantic is brutal at times. Im not opposed to cellulose but the attic is unfinished and will remain so for a while.
This all begs the question, what insulation is best used and where? If I have a first and second choice for walls, ceilings, roof... advantages/disadvantages etc. I find designing data centers is easier than the home ownership thing (at times).