revamp ranch for winter/ re insulating any suggestion
hello, i own a 1950 slabed home in mass. Im going to be fitting the home with new low e window and removeing the fiberglass insulation from the outside and filling the bays with cellose. then closeing it withe 3/8 cdx and 2″ dow tuff-r foil face. Im a carpenter for a firm that errects timberpegs, the foil foam is a common practice, i wasnt too sure how it worked doing a retro fit over existing insulated walls. im also not very familar with vynl, always installed wood.
my questions is, should i remove the very sloppy installed r11 in the walls to eliminate the paper face vapor barrier from the inside. knowing that im going to install a layer of 2″ rigid foam with taped seems over the sheathing, and refilling the bays with blown in celose? the other question, I wanted to install the vynl shake, over the foil should i strap the foil or get some long screws with large heads to fasten the vynl. (already airsealed and re insulated the attaic with blown in insualation over exsiting r19 fiberglass.)
any advice would be greatly app. thanks
Replies
I would strap it if using something other that vinyl. With most vinyl siding you want a flat surface under it. I'd go with the long scews or nails. You know not to drive them too deep so that the vinyl can expand without buckling.
i wasnt sure if using a fastener that length was consider a normal fastening schedual. Ive done some vynl but i definitly not one to jump at any jobs with it. i know i dont have enough site time with it.
Some additional food for thought since this isn't getting much mileage.
Insulation: Seems a reasonable idea to sheath the outside w/2" insulation. Personally, I'd have a tendency to remove the batt ... put it in the attic or find some use for it and then blow the walls with cellulose. Leaving the batt in place would be fine. A lot of work to pull it out and blow. And a waste of materials to toss it. Even if you give it away, it can find a use (e.g. someone's garage, etc.).
Rigid foam on the outside ... have to deal w/ the details ... around windows and such, but it's definately a good approach.
Here's
a good piece on foam "outsulation" detailing
http://www.greenbuildingadvisor.com/blogs/dept/musings/using-rigid-foam-wrb
You're not going to get enough R value with 2" of foam only, so blowing the walls is a good move. Are you talking about doing this from outside or inside?