Is it better to sweep my porch or wash it off with the hose before applying Thompson's Water Sealer?

Question

If I washed it off with water, I would certainly let it dry out for a few days before applying the water sealer. It's treated lumber. I was wondering if sweeping it would be sufficient.

Answer 1

Sweeping works unless the wood is filthy. The product tends to seal in dirt into the pores of the wood and darken it. With treated lumber you generally should be fine with a broom cleaning.

Answer 2

Thompsons water seal is the worse product you could possibly use for that deck..I'm a 37 year experienced painter and that stuff is flat terrible..and once it is used  you will have h**l redoing it as needed..It is just parrafin basically..Go get some good Cuprinol from Sherwin Williams..

Answer 3

Depends on how old the porch is. If it is fairly new, just rinse it off and seal it. If it is a few years old you will want to clean it off with deck cleaner and a stiff brush first. If it is brand new, you will want to wait a month or two before sealing it to let any excess moisture escape. You may notice some pieces of new lumber are a lot heavier than others because they have a higher moisture content. You want to let it dry first.

Though some people will recommend pressure washing, I don't because it will tear out the spring wood (the lighter colored grains that are softer).