Insulation Under Hardie Siding

The building codes are all headed the way of requiring exterior rigid foam the 2012 iecc will require 1 2 foam to boost overall.

Insulation under hardie siding.

How to install rigid foam under siding. Addition to my house. Well call me half hazard. I ve become a big fan of utilizing outsulation on all my houses over the last 2 3 years.

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. And other non nailable substrates e g. Of the three materials reviewed james hardie has the worst insulation. 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.

Over the span of a year a good siding material can save you thousands of dollars in energy costs. 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. Of course i did this all knowing my warranty would be void. James hardie is the world leader in fiber cement siding and backerboard.

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. 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. The insulative capabilities of our three siding materials are as follows.

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. Method 1 james hardie siding installed directly over continuous insulation c i and other non nailable substrates e g. But if you use wood clapboard siding foam sheathing can cause trouble. I d like to side it in fiber cement siding to match the existing house.

I m an architect in wisconsin climate zone 6b and am planning to build a 300 s f. When it comes to siding insulation is important. February 13 2013 exteriors insulation air sealing siding. I did use larger diameter ring shanked nails than specified to fasten the.