Before the first snow, probe the boards, push on every railing post, test each stair, check the ledger and its flashing, and make sure posts sit square on their footings. Clear leaves out of the gaps. Fix anything loose or soft that people lean on or step on now; staining and cosmetic boards can wait for spring.
The walk-through, top to bottom
Pick a dry afternoon and bring a screwdriver, a flashlight and your phone for photos. Work from the surface down, because the parts that hold the deck up are the ones that fail without warning.
Boards and fasteners. Press a screwdriver into any board that looks dark, especially near the house, around planters and at board ends. Sound wood resists; rotted wood lets the tip sink in. Note splits, cupped boards that hold puddles, and nails that have backed out. A raised nail head is a shovel-catcher all winter, so drive or replace them now.
Railings. Push hard on every rail post from the inside, the way someone would fall against it. It should not move. In Duluth, a deck 30 inches above grade needs guards 36 inches tall with openings too small for a 4-inch sphere to pass through (City of Duluth). A loose post is usually fastened only to the rim joist, or rotted at its base.
Stairs. Walk them slowly and watch each tread for flex. Look at the bottom of the stringers where they meet the ground or pad; that's where rot starts and frost pushes. Duluth requires a handrail on at least one side of deck stairs, sized so you can actually grip it, which matters most once the treads ice over.
Ledger and flashing. The ledger is the board bolted to your house that carries one side of the deck. From underneath, look for a gap opening between ledger and house, rust at the bolts, dark staining on the siding or rim below it, and whether metal or membrane flashing still sheds water over the top. Water behind a ledger is the slow way decks come down.
Posts and footings. Sight down each post for plumb. Probe the wood at the ground line. Check that each post still sits fully on its footing and its bracket, and that none has lifted. Duluth deck footings go 60 inches below grade, so a post that has shifted often points to a shallower footing.
| Check | What to look for | Fix before snow or in spring? |
|---|---|---|
| Deck boards | Soft spots under a screwdriver, splits, cupping that holds water | Before snow if a foot could go through; otherwise spring |
| Fasteners | Popped nails, loose screws, rust streaks | Before snow: reset or replace them, since raised heads catch a shovel |
| Railings | Posts that move when you push, loose balusters, rot at post bases | Before snow, always |
| Stairs | Treads that flex or split, stringers soft at the ground, a loose handrail | Before snow, always |
| Ledger and flashing | A gap opening at the house, rust at the bolts, dark stains or soft wood behind the ledger | Before snow; stay off the deck if it's pulling away |
| Posts and footings | Posts out of plumb, rot at the ground line, a post lifted off its footing | Shore it before snow; new footings wait for thawed ground |
| Finish | Water soaks in instead of beading, gray or peeling boards | Spring, on dry days inside the stain's temperature range |
Clear the deck before it freezes
Leaves and pine needles packed into the gaps between boards hold water against the wood and the joists underneath all winter. Sweep the surface, then run a putty knife or a thin tool through the gaps. Trex's winter care article also suggests cleaning the deck before cold weather arrives. Move planters, rugs and furniture that sit in one spot, since the boards under them stay damp and stain. Clean out any debris resting on top of the ledger flashing, and make sure a downspout isn't draining onto the deck or against a post footing.
Snow removal without damaging the deck
Use a plastic shovel and push along the length of the boards, not across them. Trex's care guide says a plastic shovel may be used on its decking and never to use a metal shovel on its early-generation boards, and its winter article says metal shovels can damage composite, that shoveling with the direction of the boards reduces dings, and that a broom handles light dustings. The same habits protect a wood deck's finish. Our advice: there's no need to scrape down to bare boards, since a thin skim left behind does less harm than gouging the surface. Clear heavy, wet snow off before it builds up, and don't pile shoveled snow against the house wall or the ledger.
Ice melt depends on the decking. Trex says calcium chloride or rock salt can be used on its decking, and tells owners of its older-generation boards to rinse it off when practical; other brands set their own rules, so check your decking maker's care page before you buy a bag. On wood, go light. The USDA Forest Products Laboratory describes "fuzzy wood" on lumber chronically exposed to salt, such as bridge decks where salt is used as a de-icer: the wood wicks salt water, crystals form in the cells as the surface dries, and over years they slowly push the surface fibers apart (USDA FPL). That's a heavy-exposure finding, and FPL says the wood beneath stays sound, so treat it as a reason to keep salt to the stairs and the main path rather than a ban. Rinse the deck in spring either way.
What to fix before snow and what can wait
Anything people lean on or step on gets fixed now: loose rail posts, soft or split stair treads, a wobbly handrail, and soft boards on the main path. So does a ledger that's pulling away or has lost its flashing, since a winter of snowmelt behind it only spreads the rot. A post that has rotted or lifted can be shored up with temporary support before snow, even though a new footing has to wait until the ground thaws enough to dig.
Spring is the time for staining, resurfacing, cosmetic board swaps and new footings. Stain needs dry wood and a run of dry days inside the product's temperature range, and those get scarce once fall nights turn cold. Our planning range for board and railing repairs is $800–$3,500, depending on how much framing is sound. See deck repair for structural work, deck staining for refinishing, and our repair, resurface or rebuild guide if the list is getting long.
Should I cover my deck with a tarp for winter?
We don't recommend it. A tarp traps moisture against the boards and keeps them from drying out between thaws, which is the opposite of what wood wants, and it hides problems until spring. Our advice is a clean, clear deck with the gaps open so meltwater can drain, and cushions and rugs stored inside. If you do cover it, leave the cover loose enough for air to move underneath.
Is it safe to shovel a composite deck?
Yes, with a plastic shovel. Trex says a plastic shovel may be used on its composite decking, that metal shovels can damage composite, and never to use a metal shovel on its early-generation boards. Push along the length of the boards rather than across them, and use a broom for light snow. Other composite brands publish their own care rules, so check your maker's instructions before using ice melt.
Can I put rock salt on a wood deck?
Sparingly. The USDA Forest Products Laboratory reports that wood chronically exposed to salt, such as bridge decks salted every winter, develops "fuzzy wood": salt crystals form in the cells as the surface dries and slowly push the fibers apart, though the wood beneath stays sound. A residential deck sees far less salt than that, so clear it with a plastic shovel and broom first, keep ice melt to the stairs and main path when you need traction, rinse in spring, and check your stain maker's label.
What deck repairs can wait until spring?
Staining, resurfacing, replacing boards that are worn but still firm, and new footings can all wait until spring. Loose railings, flexing stair treads, soft boards on the main path and a ledger pulling away from the house can't. Those carry weight or catch a fall all winter, and snow, ice and meltwater make every one of them worse before spring.
Send a few photos of anything that failed your walk-through. Request a quote or call or text (715) 919-7956; every repair gets a flat written quote before work starts, and our on-site service fee is waived when you approve the work.