Cedar impressions and foam insulation

[Tractor_Jim_CT]

Hi everyone

Has anyone installed Certainteed Cedar Impressions vinyl siding??

I've seen a thin green foam board installed on the outside walls of exisitng older cedar shingle siding before the Cedar Impressions was installed. I think the foam board is added to provide more stabilty to
the base and to make the area flat. Also some insulation.

My questions is I have new construction with 1/2 inch 5 ply douglas fir plywood sheathing and it is covered with Tyvek. Some say put the Cedar siding over the Tyvek, but I want to put the foam board over the Tyvek, then put up the siding. The foam board can not absorb water and provides additional insulation. Any exerience in this area would be greatly appreciated.

[shvl73]

I've never cared for foam for exterior sheathing as it will trap moisture. The Tyvek or any other housewrap is designed to allow moisture to pass through from inside to exterior. The foam could effectively stop that and trap the moisture against the exterior sheathing, creating a good home for ants and rot. I would think a product like cedarbreather will provide a better base for cedar siding.