Should I use water-resistant lumber for siding?

Question

Our house has a frame exterior, and rests on a pier-and-beam foundation with a brick chainwall around the sides.

We recently had the house leveled, and that resulted in a gap of several inches between the chainwall and the bottom row of siding.

Finding replacement siding for an old house like this is nearly impossible, so I want to fill the gap with a 1x6, painted to match the house.

But since the wood will be in contact with the brick foundation (and, on the porch, with the concrete porch, should I use "blue" (water-treated) wood?

I'd normally use treated lumber for anything in contact with concrete, not to mention anything outdoors, but I'm afraid that the treated lumber won't take paint well.

If it's not going to paint well, will a coat of paint on the back/bottom of the wood be enough to protect the wood from rotting due to condensation where it meets the concrete/brick?

Answer 1

I would suggest using composite or PVC lumber in this application. Composite boards are moisture and rot proof. They are made with wood fibers and recycled plastics. Most are paintable so you can match colors. The other choice is PVC boards. Some are paintable, but most should be used in the factory color. If you do paint PVC, use a product that is specifically for plastics, regular latex paints will not adhere properly.

Pressure treated lumber is a good product for this application, however it is difficult to paint. It usually has a high moisture content and must be very dry before attempting to prime and paint. Not a good base for paints, however better for stains.

I'd stick to composites in your situation.