How to choose materials and finishes to give your deck a long and healthy life.
The following tips cover the types of decking available and advice on how to finish, maintain and ready your deck for another season of outdoor living.
The best natural decking is comprised of cedar, redwood or pressure-treated pine. If you deck is made of any wood other than cedar, redwood, cypress or treated lumber it will need to be sealed annually.
While natural hardwood can be left to weather to a lovely grey, natural decks might not always age gracefully or uniformly. A deck that is regularly treated will look better and outlast an unfinished one.
Alternatives to natural wood decking are available on the market today. Composite decking, made of a combination of wood and plastic, is impermeable to insect damage, will not rot or splinter; it’s also resistant to fading and moisture. For those homeowners who want to lighten their maintenance load but don't mind the higher cost, composite decking might be the answer.
Should you need to strip, re-stain and seal an existing deck, it's important to follow the proper steps. Your local hardware store will be able to guide you through the steps and products that you’ll need. Typically, the method involves stripping, applying brightener (this product neutralizes the pH of the wood) or cleaner, letting it sit for about 3 days to dry, then applying stain or finish. While many brands of such products exist, it's best to stick to one manufacturer through the entire project.
New natural wood decks obviously won't need the stripping step, but do need to age slightly and dry. Depending on rainfall, the proper moisture level of your new deck should be reached within 2-4 weeks. After that time, the application of a good finish will greatly extend the life of your deck and save you money in the long run.
Unprotected wood decks are prey to rot, mildew, cracks and warping so prevention is essential. Unlike the old adage of leaving a new deck for 9 months to a year to "dry", it's best not to leave a new one completely bare for an entire season before protecting it.
Look for noticeable trouble spots when beginning your refinishing project, checking for areas where water is likely to become trapped at ground level, board ends and joints. Exposure to the elements also means most decks require re-finishing at least once a year, though this is also dependant on the climate and the type of wood used. This season, try this test to find out if your deck needs re-finishing: Sprinkle a few drops of water on the wood. If the water beads, the finish is fine. If the deck soaks the water up readily, it's time to re-finish.
If your deck was constructed with pressure-treated wood it will have weather resistant properties but still requires finishing. As with any other type of wood deck, it should be coated with water-repellent and regularly stained or painted. Unfinished, pressure-treated wood tends to turn grey quite quickly.
Re-finishing a deck is a lot of work, but usually can be done for a minimal price and maintaining a costly addition like a deck is smart investment protection.
DIY tip: A sanding pole is a great way to prepare your deck for finishing without doing a lot of bending. Sanding is an essential first step in achieving an even application of stain or paint.
Maintenance tip: Heavily shaded decks are prone to mildew. After initial cleaning and finishing, apply a deck cleaner annually to help keep mildew at bay. For best results, choose a cleaner containing a mildew inhibitor.
Deck finishes fall into two categories: sealers and stains. Sealers are clear finishes while stains are available in different "tones" or colours. Both sealers and stains penetrate the wood, stand up to foot traffic and protect from the elements. Paint, an opaque finish, forms a surface film on the deck and eventually shows wear from foot traffic, which is tricky to fix when reapplying the finish.
With so many deck finishes available, making the right choice may seem daunting. Take into consideration the location of your deck (does it get sun all day or shade?), what type of wood it is and how you want the finished, treated deck to look. Paint, clear finish, semi-transparent or opaque stain are all possible finishes.
Select a finish that will repel water, preserve the wood (with a mildew inhibitor) and screens out UV rays – the label should list all 3 features.
While clear deck finishes allow the natural grain of the wood to show through, they are not as effective as pigmented finishes at blocking UV rays. The best UV protection is found in a combination of pigments (colour) and chemical inhibitors, but even these must be re-applied every year. Typically, clear finishes are best suited for newer decks that haven't undergone much weathering.
Maintenance tip: Heavily shaded decks are prone to mildew. After the initial cleaning and finishing, apply a deck cleaner containing a mildew inhibitor on an annual basis.
If you are looking to apply a coloured finish to your deck, the good news is that the more pigmented the finish, the more efficient it will be at blocking UV rays and the longer you can go without having to re-apply it (sometimes up to 3 years). However, heavily pigmented finishes are a little more difficult to apply as they can leave "lap marks" where the finish may not have been applied evenly. Choose solid-colour finishes made specifically for deck surfaces, do not use regular paint on your deck); products containing Teflon are especially easy to work with.
Deck finishes can be applied with a brush, pad, roller or sprayer. A roller or sprayer can get the job done quickly but you should use a brush for the first coat of finish on a new deck. Wood will absorb more finish if it is worked in with a brush which results in better protection.
Be sure to use the right brush for the type of finish you are applying. Natural bristle brushes are usually recommended for oil-based finishes; synthetic brushes are best for water-based finishes.
Do not apply product during midday when the sun and heat are at their height, choose early morning or late afternoon to finish the project. Whichever finish or method of application you choose, be sure to let each coat dry and cure for at least 3 days.
Unless it is constructed with composite material, a wood deck is a surface which must be maintained on an annual basis. Be sure to also check for exposed nails or screwheads and loose deck boards in steps and benches. While a deck is a big commitment, if treated with care it will offer many years of outdoor enjoyment to come.