Spray foam or Spider insulation
Good day all we are in the process of building a walkout bungalow just outside of Calgary Alberta , we have had quotes for Spider blown insulation and spray foam. Our question is is it cost effective to do spray foam all over or Spider Foam all over or spray foam on the main floor and Spider foam around the basement walls. We are also going to upgrade the roof insulation to R-50 and triple glaze the main floor windows. Any thoughts would be appreciated as spray foam everywhere is our dream but we have to justify the extra cost to ourselves ,thanks. Dave & Marie
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For Calgary I would consider an R-50 minimum for the walls and R-80 to 100 for the ceilings, a double wall is still the most cost effective wall for a cold climate in my opinion.
A double wall with foam in outer and more fire retardent fiberglass on the inside ( no pink ), R 40 plus at least R5 or R10 sterofoam on the exterior ( cladded with nailing strp channels and bug barrier at bottom, painted on both side hardi board be sure to put down good old building paper before the steryofoam in the channels ), If re doing walls inside, I would add a little green foam which expands less then most just beside each 2 by 6 or 2 by 4 to stop drafts and then the fiberglass in ). Den`s Gold™ (not my trademark), paperless drywall is ideal as a finish.