Insulation Under Hardie Siding

When it comes to siding insulation is important.

Insulation under hardie siding.

According to my calculations if i want to use rigid foam insulation on the outside of the 2x6 walls with r 21 fiberglass in the wall cavities i need at least r 11 25 in order to avoid condensation on the inside. Exterior rigid foam w modern hardie plank siding details. Moisture can get trapped between the siding and the foam leading to paint failure and causing clapboards to cup and curl. Of course i did this all knowing my warranty would be void.

However if you re interested a residing project offers the perfect time to examine your home s weather barrier and exterior insulation and improve it if need be. In the end the decision to install house wrap under your siding is a personal one that you should make after discussing it with your contractor. Of the three materials reviewed james hardie has the worst insulation. Over the span of a year a good siding material can save you thousands of dollars in energy costs.

And other non nailable substrates e g. 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. Lp siding with fern strips over insulation. Last year i installed lp lap smart trim shingles and the 4x8 sheets of lp with batts all over 3 of continous xps foam using fern strips.

The building codes are all headed the way of requiring exterior rigid foam the 2012 iecc will require 1 2 foam to boost overall. Well call me half hazard. I m an architect in wisconsin climate zone 6b and am planning to build a 300 s f. Method 1 james hardie siding installed directly over continuous insulation c i and other non nailable substrates e g.

The insulative capabilities of our three siding materials are as follows. I did use larger diameter ring shanked nails than specified to fasten the. February 13 2013 exteriors insulation air sealing 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.

I ve become a big fan of utilizing outsulation on all my houses over the last 2 3 years. How to install rigid foam under siding. But if you use wood clapboard siding foam sheathing can cause trouble. Addition to my house.