Insulation Under Hardie Siding

Exterior rigid foam w modern hardie plank siding details.

Insulation under hardie siding.

Many houses built today have a double wall type of insulation with fiberglass batts fastened between the studs on the inside and rigid foam board over. Would it be better insulation if i remove the celotex and use a 1 foam board instead. Gypsum sheathing with combined thickness of 1 inch or less method 2 james hardie siding installed to furring strips that are attached through the c i. Method 1 james hardie siding installed directly over continuous insulation c i and other non nailable substrates e g.

I ve become a big fan of utilizing outsulation on all my houses over the last 2 3 years. The insulation is then behind the tyvek. Behind the 3 8 strapping is the tyvek creating an air cavity and drainage plane directly behind the hardie which prevents any moisture that penetrates the hardie and it will from deteriorating any of the other building elements. Of the three materials reviewed james hardie has the worst insulation.

How to install rigid foam under siding. And other non nailable substrates e g. The insulative capabilities of our three siding materials are as follows. February 13 2013 exteriors insulation air sealing siding.

Over the span of a year a good siding material can save you thousands of dollars in energy costs. Hardie plank recommends a maximum of 1 of foam board celotex type material under their lap siding so the 1 2 foam and 1 2 celotex would be fine.