Wood Deck Stain
Get the Most From Your Deck Finish

A deck stain must do much more than any regular house paint. It needs to resist abrasion, UV light, heat from the sun and water. Each of these represents a particular challenge that must be met in order for the deck stain to last as long as possible.

A lasting finish is what you want.

A discussion of longevity is in order. My customers always ask, how long will the stain last? The answer depends on the condition of the deck, its exposure to sunlight and water, plus the type and quality of your chosen stain.

UV light and water are the main reasons for all exterior coating failures. Most decks that we have refinished are on a sunny side that receive 6 or more hours of intense sunlight. Any lightly pigmented stain will degrade quickly with this exposure. The main defense against excessive sunlight is the pigments. The more color a deck stain has the longer it will last.

Water is also a primary concern. Rain and snow, as well as the formation of dew, will cause some damage over time. All wood species used in deck construction will or have developed splits and cracks. This allows water to soak into the wood.

A stain must resist the pressures caused by this water and allow the wood to fully dry without being harmed.

Proper preparation of the wood deck is crucial if the stain will last its designed lifetime. All damaged or rotten wood needs to be replaced.

Beginning with a clean sound surface is your first priority. Not all finishes are fully compatible with each other, so power washing and sanding may be necessary. The final goal is a smooth surface that can be walked on without worrying about splinters.

Choosing the Best Wood Deck Stain Involves Many Decisions

After many years refinishing wood decks I have developed some opinions.

• You have a choice of the amount of pigment contained in the stain. Nearly transparent, semi transparent, semi-solid and solid. The longevity or lifetime of the stain is directly related to the amount of pigment.
  
  Transparent deck stains allow the grain and texture to show through producing a great look with the least amount of pigment. Here in Colorado the average life of this finish is about 1 year. This is the least desirable stain since refinishing has to be done on a yearly basis. Available in a few colors.
  
  Semi transparent stains have a well-defined color that will show the grain and texture of the wood. This is similar to the look of interior wiping stain. The average lifespan is 2 years, maybe a little more if 2 coats are applied. Many colors are available.
  
  Semi solid deck stains are specific to one manufacture, Cabot Stains. This is my preferred brand and product for wood deck refinishing. Semi solid has more pigment than semi transparent but still allows some of the grain to show. Two coats will equal the pigment level of a solid color stain. This stain can last 3 to 4 years if the deck is properly prepared.
  
  Solid color decking stains cover the grain completely but still allow the texture to remain. Has a painted look and could have a satin sheen depending on the manufacture. Available in many different colors with custom colors possible. Can last 4 or more years depending on exposure to weather, sunlight and color chosen.
• All deck stains are available in oil base or water base formulations. Typically the oil base stains have better penetration into the wood and weather at a more predictable rate. Plus, are less likely to peel. Although oil base products smell bad and are flammable, the increased penetration is worth it.
• Color has a big affect on the stain and its ability to last. Try to choose an earth tone color that isn't too dark. Avoid the excessive use of red, red oxidizes faster than almost all other colors.

I like to use an oil base semi solid deck stain on the floor and a contrasting color on the handrails. This looks great and allows easier maintenance on the floor. The deck floor will always need more maintenance than the handrails. Using a semi transparent or semi solid oil base deck stain, a predictable schedule of 2-4 years can be established.

This allows a power washing and light sanding to be all that is needed prior to staining, at most a full stripping and heavy sanding will be necessary every other staining. This will reduce the overall cost if a painting contractor is hired and help the do-it-yourselfer have a more pleasing deck with less overall effort.

The stains usable life span can be extended with proper wood deck maintenance. This usually involves some spring cleaning and can add another year before restaining.