Staining Your Deck
A handsome cedar fence, an expansive redwood deck and a stately cedar gazebo. What do they all have in common? Aside from the fact that each is constructed of wood, their appearance and lasting quality depends upon how well they are cared for.
As a horizontal plane, a wood deck is especially vulnerable to damage from exposure to ultra violet rays of the sun and rot due to prolonged contact with water from rain, snow or irrigation. This is in spite of the fact that redwood and cedar have natural properties that make them more resistant to rot and damage from pests. All wood can use a little TLC now and then regardless of its species or whether it has been pressure treated or not.
A little time, energy and a top quality wood finish can go a long way in keeping your deck looking good. What’s more, you won’t be faced with major repair bills or, worse, the need to replace the whole shooting match. Yikes!
One of the most important measures in keeping a deck healthy is cleaning. Leaves, needles and other debris that collect on a deck should be removed – especially during the cooler months when they can trap moisture that fosters rot. Regular sweeping with a sturdy broom and an occasional rinsing with fresh water is sufficient for most decks.
Sweeping and rinsing may not be enough to get a really dirty deck clean. In this case, a solution consisting of detergent and water should be used in conjunction with a stiff bristle broom. If, however, the soap and water cleaning doesn’t do the trick and stubborn stains remain, try a more powerful cleaning using synthetic trisodium phosphate (TSP). Use the TSP in strict accordance with the directions and rinse the deck thoroughly when complete.
If the TSP cleaning doesn’t produce the desired result, use a commercial deck cleaner and/or brightener that contains either phosphoric or oxalic acid as the active ingredient. These are, in effect, wood bleaches that will remove the existing finish as well as any stubborn stains. Thus, be prepared to apply new finish to the deck. A pressure washer can be awfully helpful in removing oxidized wood fibers – just be careful when using it since you can easily damage the wood fibers by holding the nozzle too close to the wood.
Regardless of whether using soap and water, TSP or wood bleach, there are some precautions that should be taken for your safety and the health of your garden. Always wear safety goggles, rubber gloves and have plenty of ventilation. Before using deck cleaners, water down surrounding plants to saturate their root systems. Also, cover plants to avoid overspray onto leaves.
Once the deck has had the opportunity to air dry overnight, you will be able to evaluate its condition to determine whether new coat of finish is needed. If you had to use TSP or wood bleach in the cleaning process OR it has been a couple of years since your deck was last finished, a new coat of finish is probably in order.
If you’re like most people, a trip to the stain section of your neighborhood paint store, home center or hardware store can leave you more confused about stains and wood finishes than before you began your search.
When it comes to finishing wood, there are two basic types of finish – oil base and water base. Unless you marvel at the idea of spending all of your free time applying finish to your deck, we suggest that you not consider the latter and opt for an oil base product.
Beware! Not all oils are the same – some are thicker than others. The more penetrating the oil, the better the protection, the longer the finish will last. An easy means of testing penetration of a product is the “blotter test.” Using several sheets (approximately six) of white bond paper apply a small sample of finish. Be sure to use the same amount for each sample. The one that penetrates the greatest number of sheets will offer your deck the best protection.
Ultraviolet protection is another important factor in selecting a deck finish. Look for a product that contains transoxide pigments that will offer at least 90% protection from UV rays. While pigment has a great deal to do with UV protection, better finishes also contain microscopic metal particles that offer superior protection without leaving you with a “heavy-bodied” finish that hides the natural beauty of the wood. Keep in mind that “heavy-bodied stains should not be used on horizontal surfaces since they scuff easily and show wear and tear more readily.
Mildew can be a real problem with some decks, therefore it’s important to use a deck finish that contains a mildewcide. Although a mildewcide can be added after the fact, a factory-applied mildewcide will ensure a safe and properly balanced formula.
Although preparation is the better part of any painting or staining project, high-quality material and superior application techniques account for the balance of a top notch job. It also helps to follow directions on the can of wood finish. Some common cautions found on instruction labels are not to apply the finish when there is a threat of rain within 48 hours, when it is either too hot or cold, work in the shade.
Most stains and wood finishes can be applied with a brush, roller or sprayer – or a combination thereof. Whichever method you choose, don’t over apply the product. It is better to apply two thin coats rather than one thick coat. Remember to allow the first coat to dry for at least three hours before applying a second coat. And don’t forget to saturate the cut ends of the boards since they are most susceptible to rot.
The new finish should be allowed to dry for a day or two (depending upon the temperature) before replacing furniture or exposing it to traffic.