Last Updated Aug 10, 2017 · Written by Rob Schneider
Decking is exposed to the weather throughout the year. It also collects dirt and debris between the decking boards. Regular maintenance will ensure decking lasts longer and looks better. What maintenance steps do you need to take to maintain a deck?
At least once or twice a year, give decking a thorough cleaning job. Different materials require different methods.
Timber decks should be cleaned with an approved cleaning solution. Ideally, clean the decks in the morning or a cloudy day to avoid evaporation.
Start by sweeping the deck and removing dirt that has accumulated between the decking boards around the joists. While you're sweeping, look for cracks around nails and signs of rotting timber. If the cracks are large or you see rotting decking boards, think about replacing them.
Wet the surface first and then apply an approved cleanser. Apply it with a paint roller, a garden sprayer with an attachment or a stiff broom. Scrub the surface clean and rinse.
If the deck is weathered looking, use a pressure cleaner. You will probably have to reseal the deck if you use this method.
If you have composite decking, do not clean it with a pressure cleaner. Pressure cleaners can damage composite decking and will void the warranty. Scrub composite decking with a soft brush. If there are rust or leaf stains, they can be removed with a deck brightener that contains oxalic acid.
Vinyl (PVC) decking can be cleaned with a stiff broom. Rinse the deck first. Scrub in a circular motion to remove debris. Then rinse again to remove the debris.
When you clean railings, start from the bottom up. If you clean from the top down, the cleaning solution will splatter and may bleach the lower railings. After you have cleaned the railings, rinse thoroughly to get rid of all traces of cleaning solution.
During the summer months, it's a good idea to thoroughly inspect timber decks. Look for signs of rot and fixings that are coming loose. If rotting is in a small area, scrape it out with a chisel and apply a wood preservative. Only do this when the rotted timber is in a small area roughly the size of a thumb. If there is extensive rotting, replace the timber. If fixings are loose, you may be able to tighten them. If this is not possible, you may need to fill the holes to give the fittings more bite.
The ledger is the timber that is attached to the house. Ledger's are the number one cause of deck failures. Thoroughly inspect the ledger to make sure it isn't coming loose or rotting. Also inspect the joists, posts and other components of a timber deck. Anything that is rotting should be replaced.
Joists can be subject to rot. Replacing a joist can mean replacing the entire deck. Instead of replacing the deck, add a splint to rotting joists. Use galvanised screws placed 300mm apart to attach the splint to the joist. The screws must be long enough to go into sound timber. The rotting timber won't hold them.
You also need to inspect the railing. All railings should be firm. Look for cracks around nails and screws. These cracks weaken the structure. You don't need to replace the timber. Use an exterior grade adhesive and then drill a new pilot hole and fasten with galvanised decking screws.
In late summer or early fall, check the plants around the deck. If they touch the deck, prune them back. If they touch the decking or railing, they can cause mould, moss and rot. It's also a good idea to move chairs, tables and other furniture occasionally. If they sit in one position too long, they can discolour the decking.
Sealed timber decking does not last forever. Depending on weather conditions, decking sealers can last anywhere from two to five years. Don't let timber decking go without resealing when the time comes.
Start by thoroughly cleaning the deck. Then let it dry completely for a few days. Look for loose nails and screws. You may be able to pound the nails back in. If they are loose, you may have to pull them out. Avoid damaging the decking boards when you pull out nails. Use a thin piece of plywood under the hammer and you won't dent the decking boards. Replace them with larger galvanised nails or screws.
Sand the deck using 80 grit sandpaper to remove furring. Wipe off the dust. Apply sealer using a roller or brush. A brush may work better because it can get into the grain of the timber. Instead of applying one thick coat, apply two thin coats of sealer. Let the first coat dry before applying the second coat.
If you have composite decking, you don't need to seal it. However, composite decking can fade over time. Stains for composite decking are available that will restore them. Make sure you use stain designed for composite decking. The stain will not be absorbed into the decking as it would on timber decking, but it can restore the colour of the composite decking.
Decking maintenance is not a full time job. Inspect your decking twice a year and clean it at least once a year. Timber decking generally needs resealing only every few years. Stay on top of deck maintenance and any decking material will last longer and you won't have to worry about your deck collapsing.