Deck Building 17 - Waterproofing the Deck Deck Building 17 - Waterproofing the Deck

Margin of Error: None

Most Common Mistakes

1. Not sealing the deck.

There is one final step that many builders take before completing the deck.

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This is to coat the deck with a water-repellant sealer. This not only protects the wood but also extends the life of the deck by preventing the costly effect of water damage. A dear water-repellant sealer can be painted on the deck that will keep the water from penetrating. A water repellant with a mildewcide will also help redwood keep its red color and not turn black with age. The California Redwood Association recommends applying the sealer to all pieces before construction, for a more complete coverage. This sealer serves well for a base coat for other finishes. If you apply the sealer to a redwood deck after it is completed, you can apply coats at 12 to 18 month intervals to eliminate the darkening effect and preserve the beautiful buckskin color.

If wood is left unsealed, it can rot, stain, and decay, often resulting in your having to replace the wood prematurely. Because of the enduring qualities of heart redwood, this is not as much of a problem with redwood as it is with other woods. The water repellant can be applied with a brush, roller, or spray and goes on quite easily because it is rather thin and, unlike paint, penetrates quickly.

Color or a bleached effect can be added to redwood and other woods by using decking stains and bleaches. Use a lightly pigmented, oil-based decking stain to show the wood grain or a heavily pigmented, heavy-bodied stain if you prefer an opaque effect Whether the wood is smooth or rough sawn, a brush is recommended for application. Spraying is not recommended. Also note that "Shake and Shingle" paints, sprays, varnishes, or lacquers are not recommended for decks.

Bleaching agents can be applied that will give the decking a silvered weathered look. If no finish is applied to redwood, it will initially darken and then weather a driftwood gray.

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