How often do I have to use Penetreat?
Generally, just once – before the first stain is applied to the wood. However, if that stain is not kept in good condition over the years, then exposed wood can permit some of the Penetreat to leach out when exposed to moisture. In this case, reapplication of Penetreat to bare wood may be required. Penetreat will not penetrate through any coatings, so it must never be applied to stained wood – only bare wood.
