Decks and fences: a summer of care that adds ten years

A deck is the most-used structure on the property in summer and the least inspected. Decks fail, and when they do it is usually at the connection to the house, with people on them. The rest of the deck's problems are cosmetic and cheap to prevent, but that one is not. Start there.

The yearly inspection

• The ledger. The board that bolts the deck to the house. Look at it from underneath: is it attached with through-bolts or lag screws, not just nails? Is there flashing over it, keeping water out of the joint? Is the wood sound when you push an awl into it? A ledger that is nailed, unflashed or soft is a deck that should not hold a party until a Pro has looked.
• The posts. Where they meet the ground or the footing. Rot starts there. A post that sits in soil or in a pocket of concrete that holds water is on a clock.
• The joists and the beam. Look for sagging, splitting, dark stains and soft spots, especially at the ends and where they sit on the beam.
• The railings. Push hard on every post. A railing that moves is a railing that fails when someone leans. Balusters should be four inches apart or less.
• The hardware. Joist hangers, bolts and screws should be galvanized or stainless and free of heavy rust. Older decks built with the older pressure-treated wood and the wrong hardware can have connectors that have corroded through.
• The boards. Cupping, splintering, popped nails, soft spots. Individual boards are easy to replace.

If the deck is more than fifteen years old, was built without a permit, or has any of the ledger or post problems above, a deck Pro or a home inspector should look. It is a short visit.

Cleaning and sealing

Pour water on the boards. If it beads, the finish is working. If it soaks in, it is time.

• Clean with a deck cleaner, not just a pressure washer. High pressure at close range raises the grain and tears the wood; if you use one, keep the pressure low and the wand moving.
• Let it dry for two dry days.
• Seal or stain. A penetrating oil-based or water-based stain with a water repellent, brushed or rolled on, two thin coats. Film-forming finishes and paint look good the first year and peel the second. Solid-color stains hide old wood but need more prep.
• Every two or three years for a clear sealer, three to five for a semi-transparent stain, in most climates. The south-facing deck goes first.

Fences

Same wood, same rules, simpler structure. The failure is the posts, at the ground. Look for lean, and push on each post. A rotten post can be replaced without replacing the fence; a set of posts leaning together is a fence that is coming down in the next big wind. Keep the sprinklers off it, keep the mulch and soil off the bottom rail, and clean and stain it on the same schedule as the deck.

When to rebuild

A deck with a bad ledger, multiple rotten posts or beams, or a structure that does not meet the current code for its use, is usually cheaper to rebuild than to repair piecemeal, and the rebuild gets a permit and an inspection. Composite decking on a new frame costs more and ends the sealing forever; a good pressure-treated deck, sealed on schedule, lasts twenty-five years. Either way, the ledger is flashed and bolted this time, and you check it every June.