Deck Repair near you

Walk the deck, then look underneath with a flashlight. Probe suspect wood with a screwdriver: sound wood resists, while rotted wood is soft, spongy or pulls away in fibres. Pay extra attention wherever water collects and where the deck meets the house.

Some problems are more than wear. A guard that gives way when someone leans on it, or a ledger pulling away from the house, can lead to a fall or a collapse, and failures like these tend to happen when the deck is most crowded. If you see either one, keep everyone off the deck, or at least away from the damaged area, until a qualified contractor has assessed it.

The decking is the easy part to judge. What decides between repair and rebuild is the frame underneath: ledger, beams, joists, posts and footings. If they are sound, new boards, guards or stairs can keep the deck going for years. If rot, corrosion or heaving has spread through them, new material on top only hides the problem. Structural work beyond replacing surface boards is a job for a qualified contractor, and a rebuild is a chance to change the size, height or material, as the deck construction page explains.

Swapping a few rotted boards is the one repair many handy owners take on: the old board comes up, the joist beneath is checked for soft spots, and a new board of the same thickness goes down with corrosion-resistant fasteners. If the joist is soft too, or the damage runs under several boards, stop there and call a pro. Guards, stairs and anything that holds the deck up are structural and belong to a contractor.

Health Canada notes that residential decks, fences and play structures built before 2004 are likely to be made of lumber treated with chromated copper arsenate (CCA), which is no longer available for residential construction. That calls for care during repairs, when the wood is cut, sanded or torn out. For an old CCA deck you're keeping, Health Canada suggests considering a sealant every year and replacing wood that shows damage such as rot or scraped surfaces, to avoid the release of arsenic.

Once repairs are done, a thorough cleaning and a fresh finish help new and old boards weather together and protect the wood you kept. Remove mildew, flaking finish and grey surface fibres with a cleaner suited to the wood, let it dry fully, then apply a finish compatible with what's already there, or strip it back if the old coating is peeling. Pressure washing needs a light touch on wood, since aggressive settings damage the surface; the pressure washing page explains the precautions, and the exterior painting page covers stains.

Repair rules are local. In Montreal, the Ahuntsic-Cartierville borough's page says no permit is needed to maintain or repair a deck, balcony, porch or stoop, but if you decide to use materials different from the original ones, you must inform the permit counter; replacing one requires a permit when its floor is more than 60 centimetres above the ground. In Toronto, where a permit is required to build a deck more than 60 centimetres above the ground, ask the city whether rebuilding the frame, guards or stairs of a deck that high needs one.

In general, replacing surface boards is maintenance, while replacing or altering the ledger, beams, posts, footings, guards or stairs is structural work that may need a permit, and your contractor should confirm with the municipality before starting. If a previous owner built the deck without a permit, a repair can bring that to light, so it's worth sorting out before you sell.