How to Prepare Exterior Wood for Staining
Time Required: Over 1 day
For professional-looking results when staining, its essential to properly prepare your deck. The type of preparation you need to do depends on the condition of your wood. New wood requires minimal preparation, while old or damaged wood will require additional steps to ensure the best results when staining. This guide will walk you through the steps of preparing your deck for staining.
New wood preparation:
- Use a wood cleaner to remove dirt and pollen. Apply the wood cleaner per the manufacturer’s instructions.
- Rinse away the cleaner using a power washer on low to moderate power.
- While the deck is wet, check for mill glaze (water beading which shows that the surface is not porous.) If mill glaze exists, either sand lightly, or scrub the area until water is easily absorbed into the wood.
- Also while the deck is wet, check for black spots that might indicate mold or mildew (yes, even on new wood.) If you find mold or mildew, treat with an appropriate product.
- Allow to completely dry.
Existing wood preparation:
Tip: The condition of existing wood can span from lightly used to heavily damaged. Always follow the manufacturer’s specific instructions for wood prep when applying their product.
- If there is prior paint or stain on the wood, remove it with a paint or stain stripper.
- Clean the wood with a wood/deck cleaner.
- Inspect for mold and mildew and treat with an appropriate product to remove.
- If you have a weathered solid color on your wood already, check for adhesion by cutting a small X in a few random spots, cover the cuts with tape, press firmly, and quickly remove. If old stain or wood flakes come off, use a stripper to remove the existing stain. Sand as necessary to remove additional flakes.
Mixed wood preparation:
Mixed wood consists of new and old boards, usually the result of replacing damaged or unsafe boards on your deck over time.
- Stripping or sanding will likely be required if you want your deck to have a uniform appearance once it’s stained.
- Thoroughly clean the deck of dust after sanding.
Tip: This may seem like an insignificant step, but remember: if the wood looks significantly different before you stain, it will when you are done as well.
- Pour a cup of water over a few areas around your deck. If the water stays beaded after ten minutes, there’s still a previous stain coat that you must remove.
- Check the weather in your area – most stains require dry wood and a 24-hour window of dry weather in order to cure.
- Once your deck is clean, mold/mildew and splinter free, and all previous coatings are removed, you’re ready to stain!