The fifteen-minute deck safety check

Do this in April or May, after the ground has thawed and the deck has dried out for a few days. Winter is when things move; spring is when you can see what moved. If the deck is older than you are, or you've never looked under it, this is worth the fifteen minutes.

1. The ledger, where the deck meets the house

This is the one that matters most. The ledger is the board bolted (it should be bolted) to the house that carries one whole side of the deck. Get under the deck with the flashlight and look at it. You want to see bolts or structural screws in a staggered pattern, and metal flashing tucked up behind the siding above it. Nails alone, no flashing, dark stains, or wood that a screwdriver sinks into means water has been getting behind it, and that's a call-someone problem, not a wait-and-see one.

2. Posts and footings

Look at the base of every post. A post sitting on a concrete footing with a metal bracket is doing fine. A post buried in the dirt, or sitting in a low spot where water pools, is rotting from the bottom. Push the screwdriver into the wood right at the soil line. If it goes in, the post is done. Also look at whether the posts are still plumb; a deck that's leaning was probably heaved by a shallow footing over the winter.

3. Joists and hangers

Still under the deck. The joists are the boards running under the decking. Look for dark, soft patches, especially at the ends where they sit in metal hangers, and check that the hangers are actually nailed on all their holes and not rusted through. Sagging between supports or a joist that's split along its length means it's carrying less than it should.

4. The boards

Walk the whole deck slowly and feel for give. Soft spots, boards that flex more than their neighbors, and boards with cupped edges or long splits are the obvious ones. Poke suspicious boards from underneath too; rot often starts on the bottom where the board sits on the joist. A few bad boards are a repair. Bad boards everywhere with a good frame under them is a re-deck.

5. Railings

Grab the top rail at each post and lean on it, hard, the way a guest will at a party. It should not move. A railing that wobbles at the post has usually lost its connection to the frame, which is a hardware fix if the post is sound and a replacement if it isn't. Check that the balusters are all present and that a kid couldn't get through the gaps.

6. Stairs

Bounce on each tread. Look at the stringers, the sawtooth boards the treads sit on, for splits and rot where they touch the ground. Grab the stair rail. Stairs get more weather than the deck because water runs down them, and they're the part people fall off.

7. Fasteners and hardware

Everywhere you look, notice the metal. Rusted nails, popped screws, corroded brackets, and hangers with missing nails all mean the same thing: the connections are weaker than they were. Older decks built with plain nails and untreated hardware were never meant for this climate. Upgrading to coated screws and connectors is one of the cheapest repairs there is.

What to do with what you found

Soft boards, a loose rail, or a bouncy stair are repairs, and worth fixing before summer. A soft ledger, rotting posts, or a leaning frame are the reasons to stop using the deck and get it looked at; that's usually a replacement conversation. Either way, we'll come look at no charge and tell you which it is.