Why Deck Stains Fail - Exterior Hardwood Finish Failures

By Steve Getsiv, 11/30/18

How does your commercial wood exterior look? Is it grayed out, weathered, and blotchy? Are you getting frustrated that your outside deck was just stained and the stain is slowly deteriorating? The issue that you are seeing has to do with inexpensive stain finish that is being applied and used. Components in these finishes make a HUGE difference on whether the deck stain will last.

Batu Decking Dartmouth College 5/4x4 Nova USA Wood
Exterior wood moves way too much. Wood moves due to the change of moisture, specifically in states such as California where there are long dry seasons. The humid weather in the California winter causes the wood to pick up moisture. This moisture allows the cells to expand, creating swelling in the wood. This movement can create a quarter inch of water on a 6-inch wood piece, ending with 20% moisture content. Most stains cannot withstand this and end up failing.

If you purchased a low-cost wood finish to be applied to your exterior deck and the stain is already weathering, it is because the stain uses dyes. Dyes fade and dry out leading the powder residue to wash off in the weather. Dyes are not color stable and lead to wood decay.

Most exterior wood stains are based on a few products. The two common products are water-based stains and oil-based finishes.

Water-based finishes have no protection to exterior wood deck fibers. The finish adds a beautiful color but does not provide any protection because the stain does not harden on the wood. This creates a beautiful finish but it doesn’t last longer than a year.

Vegetable oil and Linseed Oil have similar effects on exterior wood, too. The oil is not able to harden causing it to be evaporated. These oils dry at room temperature, which ends up taking months. These oils are known to create mildew and fungus problems on the wood, do not have any waterproofing qualities and crack after hardening. They are inexpensive stains that will cost more in the end.

What you are looking for is Tung Seed Oil. Tung Seed Oil is a high-end, marine grade, finish that hardens deep inside the wood. It dries and becomes flexible on the wood and does not evaporate over time. It is water, acid, and mildew resistant. It is polymerized to make the oil dry more quickly. Without polymerizing the oil, it will take up to 3 months for the wood to dry.

ExoShield Marine Grade Tung Oil Deck Stain
ExoShield is the best hardwood finish out right now. Our secret formula combines Tung Seed Oil and polymerizes the wood decking, creating outstanding UV protection, color stability, and a lasting finish.

If you use a higher quality finish, you spend less money on maintenance and the exterior looks much better. Everyone wants the natural wood look, but a few months after refinishing, your wood starts to look nasty if using a cheap stain. Within two years of using inexpensive finish, you will have to go back and redo the entire process.

In decking applications our product is guaranteed to look good for one year, and instead of getting the whole deck sanded and pressure washed for another finish, you simply have to recoat it with our ExoShield stain. Siding applicaitons require maintenance every 3 to 5 years.

By Steve Getsiv, 11/30/18

"I would like to hear more about surface preparation before staining."

By SteveG on 12/06/18

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