Insulation Under Hardie Siding

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Insulation under hardie siding. I d like to side it in fiber cement siding to match the existing house. How to install rigid foam under siding 1. I get asked if this or that in the in the cavity works as well as foam under the siding.

Method 1 james hardie siding installed directly over continuous insulation c i and other non nailable substrates e g. Measure the walls from top to bottom with a tape measure and buy either 4 by 8 foot or 4 by 9 foot sheets of rigid. This has been discussed here but we still don t have answers.

Set panels on the wall starting at one end of the house align the edges with the corner and bottom of the wall and. 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. Addition to my house.

As many things in building science go you my dear reader have to learn something. One new wrinkle for many builders is walls built with fiber insulation between the studs plus rigid foam insulation applied over the outside walls. I have been told by some seasoned pro s that they don t recommend insulation board under hardie plank because it can look wavey.

February 13 2013 exteriors insulation air sealing siding i ve become a big fan of utilizing outsulation on all my houses over the last 2 3 years. Others the big debate with hardie plank windows siding and doors contractor talk. And other non nailable substrates e g.

I thought i should show why continuous foam under the exterior siding is so important. 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. The building codes are all headed the way of requiring exterior rigid foam the 2012 iecc will require 1 2 foam to boost overall efficiency so i m really not too far ahead of my time with this building technique.