When staining exterior wood surfaces, procedures vary depending on whether the wood is treated, untreated, or previously stained.
New wood (treated or untreated)
- Check for any glossiness on the wood, which can prevent the stain from penetrating into the wood and adhering to the surface. Sand glossy area with 60-grit sandpaper for better adherence.
- Allow wood to dry. If the humidity level is more than 12%, the stain can’t penetrate the wood adequately.
- Remove sand, dirt, grease or other contaminants that might prevent the stain from penetrating. Even if your wood is new, check for signs of mold on the surface. To remove mold, wash surface with a solution of 3 parts water to 1 part bleach and a scrub brush.
Stained wood
- Verify solidity of every plank and replace those that are damaged or starting to rot.
- Wash the surface with a solution of 3 parts water and TSP to 1 part bleach. TSP is a degreaser used to wash surfaces before painting or staining. Scrub the surface with a broom or scrub brush. Rinse with clean water and allow to dry until wood reaches a humidity level of less than 12%.
- Scrape away any of the old stain that might flake.
- You’re now ready to stain!