How to Stain a Pressure-Treated Wood Deck

Working from Home May Provide the Extra Time You Need to Rejuvenate the Core Component of Your Backyard Oasis


Picture of Child Sitting on Deck

Backyard decks have become a sanctuary for many that have become part of the work from home legion.

Unfortunately, long work commutes and periods of time away from home left many of those decks neglected due to a lack of time. Stain faded, boards rotted, and stairs wobbled.

A benefit of working from home is you now have time to tend to overdue projects like deck maintenance. Instead of heading to the cafeteria for a coffee break, you can replace a weak deck board or two. And there’s no going out for lunch for those that work from home. That time is much better spent applying a new coat of stain to that deck section badly bleached by the sun.

In this In The Mix blog, we look at the process of staining an old – or new – pressure-treated deck.

When to Stain A New Pressure-Treated Deck

Many are tempted to immediately apply stain to a new pressure-treated deck (or replacement boards). Doing this may make the deck look good temporarily, but soon it may look blotchy. The blotches are a result of the high moisture content found in new pressure-treated wood. The excessive moisture prevents the stain from absorbing correctly, giving it an uneven appearance. This not only looks bad, the wood is not uniformly protected.

To maximize stain performance, wait until the wood has had time to dry before applying it. How long you should wait is a topic of much debate. Your wood and stain manufacturer are the best source for the correct information. They can tell you the highest percentage of moisture that is acceptable to apply stain. You can check the percentage with a moisture meter commonly available in stores and on the Internet. If you don’t want to purchase a meter, you can also perform a simple water or pressure test.

Finally, adhere to your stain manufacturer’s recommended temperature range for application to achieve the best results, regardless if the deck is new or old. Applying stain below the recommended temperature range can lead to sticky deck boards and a variety of other issues that can be difficult to remedy.

Prepping Your Deck for Stain

Again, follow the stain manufacturer’s instructions to prep your pressure-treated deck properly before applying stain. New decks typically just need a light cleaning with a broom, wet/dry vac or blower to remove sawdust, dirt and debris from construction. If you waited longer to apply the first coat of stain (e.g., through winter), use a commercial deck wash to clean surface grit and grime before staining.

Prep existing decks for stain the same way you would a new deck. Many also pressure-wash older decks that have weathered significantly. Doing this removes all or most of the existing stain and returns the wood to a like new appearance. Wait several days without precipitation before applying a new coat of stain to a pressure-washed deck.

The final step before applying stain is masking off any adjacent surface you don’t want to stain (e.g., vinyl siding). The stain can be difficult to remove if it gets on these surfaces. If you do get stain on your siding, wait for it to dry and then remove it with a polycarbide abrasive wheel attached to your drill. Apply just enough pressure to remove the stain, not any of the vinyl. Still, it’s always better to mask off items than trying to remove stain that got on.

Water or Oil-based Deck Stain?

Deck stains are available from a wide-variety of manufactures at many price points. Like paint, there are water and oil-based options.

Water-based deck stains are the most popular because of their easy cleanup and mass availability. Some prefer oil-based stain for its exceptional durability and rich appearance. However, it may not be available in some areas due to environmental regulations related to volatile organic chemicals (VOCs). Fortunately, the performance of water-based stains has improved over recent years, and manufacturers claim some are now as durable as their oil-based cousins.

How to Apply Deck Stain

Picture of applying wood stain to a deck railing using a brushMany applicators can be used to stain your deck including brushes, rollers, rags, microfiber pads, and sprayers (e.g., pneumatic, airless, pump). Microfiber pads are increasingly popular for staining deck boards (they don’t drip as much as rollers but hold a comparable amount of stain). Sprayers  work well for staining irregular shaped deck components like railings. However, sprayers require extra prep time to limit over spray issues and can clog easily.

Regardless of the applicator used, maintain a wet edge when applying stain to avoid dark areas where wet stain overlaps stain that has already dried. This situation is common when only part of a board is stained before moving to the next one instead of staining the full board length at one time.

Deck Stain Clean-up

Clean up brushes, rollers, pads, and sprayers according to the stain manufacturer’s instructions.

Oil-based stain requires mineral spirits or a similar solvent. These products can be messy, and disposal is an issue (they should never be poured down the drain). Water-based stain cleans easily with water, a primary reason most do it yourselfers prefer it over oil-based stain.

Whether using oil or water-based stain, remove as much stain as possible from the applicator. Any stain that is not removed hardens when allowed to dry, and the applicator may no longer be usable.

Enjoy Your Deck

Adhere to your stain manufacturer’s recommended drying period before using your freshly stained deck. Then enjoy your backyard oasis as long as possible before the first snow flies!

ProQuip Tank Agitators for Stain and Paint Manufacturing

ProQuip has supplied a wide range of mixing solutions to the stain and paint manufacturing industry including blend tanks, let down tanks and high speed dispersers. Processes include:

  • Pigment Dispersion into Solvent

This is typically done using a high speed agitator that uses a high shear impeller with tip speeds of 3,000 to 6,000 ft/min.

  • Letdown and Tinting

Letdown and tinting is blending the pigment concentrate (made with the high speed disperser agitators) with solvent and other additives. This is typically done using dual axial turbines or combination axial/radial turbines with tip speeds of 800 to 1000 ft/min. Blend-times are usually 10 to 15 minutes. Shafts have extended keyways to allow adjustment of the upper impeller to produce sufficient surface movement to pull down additives added at the liquid surface. Tanks are usually square to avoid baffles and can have rounded corners for easy cleaning.

  • Storage

Stain and paint are typically stored using low speed axial turbines or ProQuip HiFlow impellers.  Storage of latex paint sometimes requires up-pumping HiFlow impellers to prevent skinning over of the liquid surface.

For More Information

For more information on ProQuip mixing solutions for stain and paint manufacturing, email or call us at 330-468-1850.