How should I frame and insulate?
I am building a 2300 square foot, 1&1/2 Story, home for my family on the seacoast of New Hampshire. The building’s foundation is going to be a slab on a frost wall with radiant heat. The footings were just poured and I am about to order material for the frame. I want to build a simple fairly energy efficient building.
I am considering either a PERSIST structure with 2*4 walls and 4″ of rigid insulation on the walls and 8″ on the roof or a standard 2*6 wall and 2*12 rafters, insulated with cellulose, with a thermal break in the walls and roof somewhere. If I build the PERSIST structure I’ll insulate it myself but if I go with cellulose I’ll hire a sub to blow in the insulation. Assume I am going to hit the same R-value with either method.
If I have cellulose blown in how much polystyrene insulation should I install outside the sheathing as a thermal break or should I strap the inside of the wall instead?
Finally a section of the back of the house is within feet of a 8′ high chunk of ledge which will splash water onto the exterior of the building when it rains.
Which method is better for my situation?
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Replies
I think PERSIST is overkill but something similar is the way to go. Here the exterior rigid foam guys use two perfectly fitted layers of taped foam. I think complete details of what they do may be available via some consulting time.
所以贴泡沫,2层2“,总4”。Rainscreen over the top or viny siding. Vinyl siding drains like rainscreen only better. If you are using wood or cement board siding I would add two extra coats of finish on the ledge side and rainscreen it.
Question. How possibly are you building already without finished plans, without finished complete detail sheets, withou engineers stamp, and without building department stamp? And who is the GC? And have you signed up all your subcontractors which for some homes may be as many as 20 companies or more.
I am building the house myself and have plans but I'm making final decisions on some of the elements of the design as I go. I work in the trades so I am bringing in contractors as I need them. As for the engineers stamp and building dept. stamp all you need to do here is submit the drawings and they issue a building permit. Although when I say "all you need to do" I can't use vinyl as I'm in a historic district and it is not allowed. Thank you for the advice.