Exterior Rigid Insulation and Siding
Hi,
I recently completed a single family home in Va with 6″ stud walls (cellulose) and exterior rigid insulation. I wanted to have 2″ minimum exterior rigid, but the contractor pointed out that the literature on the specified siding (Hardi-Plank) only supported up to 1″ rigid insulation. They also did not seem to support a rainscreen detail of any type when rigid insulation was used.
On the phone, the tech support would say that 2″ rigid w/ rainscreen was compatible with Hardi-Plank, but the lack of literature in the installation instructions etc was troubling, especially as it related to maintaining any warranties.
Has anyone had any experience with 2″+ of exterior rigid insulation installed with exterior cement board or siding in a rainscreen configuration? Were you able to get literature from the siding manufacturer that indicated that type of installation was acceptable, and maintained warranty?
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Replies
Grayson,
Several people have raised this question on our Q&A pages recently. The short answer is, Yes -- you can install Hardie siding on furring strips screwed through 2 inches or more of rigid foam.
Here are some links:
Can I really use 2" of rigid insulation under fiber cement siding?
Anyone back-vented Hardie lap siding over exterior insulation?
Should you use furring strips under Hardie siding?