I purchased a home with an enclosed deck. Exterior walls are wood. Looks to be some wear and tear including holes from woodpeckers. No visible soft spots or signs of wood rot.

Looking to replace windows and add vinyl siding. Would there be any issues adding vinyl siding to this surface? Would anything need to be treated/repaired first or would affixing fanfold insulation and tyvek house wrap suffice underneath?

enter image description here

2 Answers 2


This is a classic example of a vinyl overlay situation. Assuming conventional framing underneath the plywood siding, there should be no issues installing foam insulation and house wrap.

I would use at least 3/4" foam, though. Fanfold is little more than house wrap itself, and in my assessment was designed as a two-in-one solution to eliminate the need for house wrap in some cases. It provides very little R value itself. Since you're replacing the windows you could easily go with 1" or 1½" foam to add substantial energy efficiency.


No issues covering with vinyl. In fact, it's the main advantage of vinyl that you have to do so little prep. Some people add some insulation below vinyl, but that depends on your intended use of the space, and current insulation.

Aesthetics is another thing. I'll always prefer wood siding, but vinyl is just too cheap for most people to justify the expense of wood.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.