Q. When putting siding on a house covered with side board, should you remove the rotten boards first, even if they’re just rotten on the ends? Would there be any problems with the new siding if I didn’t remove the old, rotted boards?
If you’re installing fiber cement siding, professionals tell me you should remove all existing siding. If you’re installing vinyl siding in place of existing hardboard siding, which I’m guessing is the more likely scenario, I definitely recommend replacing any rotten wood prior to putting on the new siding.
You can install vinyl siding over boards that are slightly weathered. You could potentially end up with a few major problems if the boards are rotted or if the wood is soft.
First, the nails used to hang the new siding need to be anchored into a solid surface. If the wood is soft or rotted, the nails will not be secured into that surface. The result? Your new siding could literally fall off.
Second, the moisture left behind the new siding in the rotted wood is an invitation for trouble, including bugs, mold and mildew problems. Because they’re concealed, those small issues could become very big – and very expensive – very quickly.
Get a qualified siding professional to evaluate your existing surface and make a recommendation. Be sure your siding pro thoroughly inspects the surface with you, and share your concerns about the existing wood during the estimating process. That way you can determine potential problems before starting the project.