Finishing, Maintenance, and Inspection

Southern Pine

Deck Finishing, Maintenance, and Inspection

You’ve built the perfect deck, and now you want to maintain it for years of use. Great! Unfortunately, deck and porch wood and finishes are exposed to weather, which can be severe in certain areas, which is why you need finishing, maintenance, and inspection guidance. 

The horizontal surfaces, especially in decks, are often exposed to the sun’s direct rays and tend to collect moisture; therefore, the weathering process is greatly accelerated. As repeated wetting and drying cycles occur, surface checks (small cracks) and end-grain surfaces begin to retain moisture.

Painting and Staining

Pressure-treated Southern Pine lumber can be painted or stained. At a minimum, a clear water-repellent coating is recommended for decking boards. If you want color, semi-transparent stains are best.

Take note: paint and solid-color stains, which show wear on frequently used pathways, are not recommended for decking boards or stair treads.

If you purchased wet wood (wood that is not re-dried after treatment), allow the wood to dry before finishing. Drying time will depend on the product used and climate.

For guidance on finishes, select the condition of your Southern Pine decking product below.

STANDARD TREATED WOOD, WET

Layout
Do not apply paint until the wood is dry both internally and on the surface; otherwise, as the wood dries, escaping moisture will cause blisters and poor paint adhesion. It’s recommended you wait six months before applying oil-based or latex paint. Once the wood is dry, painting treated wood is no different from painting untreated wood. Applying a primer is suggested for the best results.
Stain

A semi-transparent stain will show wood grain, while a solid-color stain will hide the grain but still allow the wood texture to remain visible. Solid-color stains are heavily pigmented and form a film, just as paint does, so the recommended wait time to apply an oil- or water-based stain is the same as that for paint (at least six months). Semi-transparent stains, however, do not block moisture movement, but it’s still recommended to wait 30 days before applying a semi-transparent oil-based stain. Follow the manufacturer’s instructions for the best results.

Water Repellent

Most water-repellent product instructions recommend an immediate application, which is ideal. Other product instructions recommend a slight delay. Either way, applying a water repellent every year or two is recommended. Follow the manufacturer’s instructions for the best results.

TREATED WOOD WITH WATER REPELLENT

Paint and Stain

Recommendations are the same as for standard treated wood, but it may take longer for the wood to dry. Therefore, the delay may be longer. It’s recommended you wait 30 days before applying an oil-based semi-transparent stain to water-repellent treated wood and at least six months before applying an oil-based solid-color stain, oil-based or latex paint, or a water-based stain.

Water Repellent
An initial coating of topical water repellent is not as critical for treated wood infused with a factory-applied water repellent, although it does provide additional surface protection. Water-repellent treated wood generally will not need a water-repellent coating for about a year. Applying a water repellent every year or two is recommended.

RE-DRIED AFTER TREATMENT (KILN-DRIED OR AIR DRIED)

Paint, Stain, Water repellent

Moisture content of re-dried wood is already in balance with atmospheric moisture levels, so coating can proceed immediately.

Deck Maintenance and Inspection

In general, you should apply an effective water repellent as soon as possible to help protect your project against moisture damage and reapply about every two years. You can also use deck brightener to revitalize a weathered appearance.
Inspect your deck once a year for signs of decay, the condition of structural connections and guard railings, etc.

THE SPLASH TEST

When should you apply or reapply a finish?
Here is a simple test regardless of a deck’s age:

  1. Ensure the wood surface is thoroughly dry.
  2. Then, pour water and observe how it responds.
    1. If water droplets form on contact:
      1. for newly constructed decks, the lumber is not yet sufficiently dry to accept finish.
      2. for existing decks, the finish is performing satisfactorily.
    2. If water is absorbed into the wood:
      1. it’s time to apply a sealer or stain.

To learn more about proper planning, building a deck, building a porch, and finishing and maintenance, check out our Southern Pine Decks and Porches publication, a comprehensive guide to the specification and construction using pressure-treated Southern Pine.

Click below to learn more about: