What should be on my yearly deck maintenance checklist?
Short answer
Once a year, ideally in spring after the rains, give your deck a working afternoon: clear every gap between boards, wash it with a wood-safe cleaner, check and snug up fasteners and hardware, look at the ledger, posts and stair stringers for soft wood or standing water, trim back plants and adjust sprinklers, then do the water test and recoat what needs it. Keep a note of what you found so next year you can see what has changed.
Clean and clear
Start with the gaps. Debris packed between boards holds water against the joists and is the most common cause of a deck rotting from the top. Run a putty knife through every gap, then sweep or blow the surface. Wash with an oxygen-bleach wood cleaner and a stiff brush, rinse, and let the deck dry for two or three days.
Clean the underside too if you can reach it. Cobwebs, leaves and bird nests on top of the joists and in the hangers hold moisture exactly where you do not want it.
Hardware and fasteners
Walk the surface and look for screw heads that have lifted. Drive them back down or replace them; a proud head means the board has moved or the screw has lost its grip. Then go underneath with a flashlight and look at every joist hanger, the post bases, the bolts through the posts and the lag screws or bolts in the ledger.
Surface rust on galvanized hardware is cosmetic. Flaking, pitting, rust streaks running down the wood or a hanger with its coating gone means it is time to replace that piece. Near the coast, hardware often fails before the wood does. Snug any bolts that have loosened as the wood shrank, but do not crush the wood.
The structure underneath
With a screwdriver, probe the places where decks actually fail: the bottom of each post, the stair stringers where they touch concrete or soil, the ends of joists at the beam, and the ledger where the deck meets the house. Sound wood resists the tip. Soft wood takes it easily and should be looked at before anyone stands on that part of the deck.
Look for daylight and for water. Is there flashing above the ledger, and is it intact? Does the ground under the deck drain, or is there a low spot where water sits after a storm? Is anything touching soil that should not be?
- Post bases and anything within a few inches of grade.
- Stair stringers, treads and the landing.
- Joist ends, especially the outside joists that catch rain.
- Ledger, flashing and the house wall just above it.
- Railing posts where they bolt to the frame.
The finish
Once the deck is clean and dry, sprinkle water on the sunniest boards, the rail cap and the stair treads. If it soaks in, that wood gets a thin maintenance coat of the same type of finish that is on it now. If it beads, it can wait. The ends of boards, the stair nosings and any cuts always get a second pass, because that is where water enters.
Composite decks skip the finish entirely but still need the cleaning, the gap clearing and the hardware and structure checks. The frame under composite is still wood.
Around the deck
Trim back shrubs and vines so air moves along the edges and under the deck. Move planters onto feet and shift them a few inches so the boards beneath can dry. Run the sprinklers for a minute and watch where the water lands; any head that wets the deck, a post or the fascia gets redirected or capped.
Check furniture feet for rust and replace worn glides with plastic or rubber. Pull up outdoor rugs and let the boards under them dry out for a few days before putting them back, or leave them off altogether.
Write it down
Make a quick note of what you found and what you did: which boards were oiled, which hanger looked rusty, where the wood felt a little soft. A photo of each trouble spot helps. Next year you will be able to tell whether a check has grown or a soft spot has spread, and that is far more useful than trying to remember. It also gives a builder a head start if a repair is ever needed.
Related questions
How is this different from a deck safety inspection?
A safety inspection is about whether the deck can be used: the ledger connection, the railing strength, the footings. This checklist is the routine care that keeps a sound deck sound. The two overlap at the structure check, and if the probe finds soft wood or a hanger has rusted through, you have moved from maintenance to repair.
Can I do all of this myself?
Most of it, yes: clearing, cleaning, finishing, tightening screws, moving planters and adjusting sprinklers are homeowner jobs. Replacing structural hardware, repairing a ledger or dealing with a soft post is where a builder earns their keep, and anything to do with deck lighting or outlets belongs to a licensed electrician.
What time of year should I do it?
Spring, after the rains have ended and the wood has had a week or two to dry. That is when winter damage is visible and when the finish can be renewed before the summer sun. A shorter walk-through in the fall to clear debris and check drainage rounds out the year.