Winter is hard on decks. Freeze-thaw cycles work like slow crowbars on every connection point, snow loads press down on framing that may already have years of moisture damage behind it, and the whole structure sits unattended for months without anyone noticing what is quietly changing.
When temperatures warm and you finally step back outside, a walk-across-the-deck check is not enough. Here are the 12 things worth actually looking at.
A Quick Reference: What You Are Looking for and How Serious It Is
| Issue | Where to Look | Urgency Level |
| Ledger separation from house | Behind the rim board, at the house wall | High, address immediately |
| Post rot at base | Ground contact point on each post | High |
| Rusted or missing joist hangers | Underside of deck, each connection | High |
| Beam decay | Beam-to-post bearing points | High |
| Loose or missing fasteners | Deck boards, railing posts | Medium |
| Wobbly deck railing | Grab each rail section and push | Medium |
| Soft deck surface boards | Walk the entire deck surface | Medium |
| Water pooling on deck | After a rain, observe runoff pattern | Medium |
| Large cracks in deck boards | Horizontal surfaces, board ends | Low to medium |
| Rust stains on deck surface | Around screw heads and hardware | Low, monitor |
| Small holes in wood | Framing and boards, look for frass | Low, assess for insects |
| Dirty or discolored surface | Full deck surface | Low, maintenance |
Start Here: The Three That Matter Most
Some issues are cosmetic. These three can end a deck quickly, so they go first.
1. The ledger board connection. This is the board that attaches your deck directly to the house. It is also where most deck collapses originate. The U.S. Consumer Product Safety Commission has tracked thousands of deck and porch-related injuries over the years, with ledger failure consistently identified as a leading structural cause. Look for gaps between the ledger and the house framing, any pulling-away movement, missing or corroded lag bolts, and any sign that water has been sitting behind the board. If the flashing has lifted or cracked, water has almost certainly been getting in.
2. Support post condition. Go low. Check each post at the base, where it meets the footing or sits close to the ground. Soft wood at the base of a post means rot has started, and that post is no longer doing the job it was built to do. Press firmly with a screwdriver. Solid resistance is good. Any give means the wood fiber has broken down.
3. Joist hanger integrity. These metal connectors hold the joists to the beam. Climb under the deck if you can and look at each one. Missing fasteners, cracked metal, and heavy surface rust all reduce the load capacity of the whole deck frame. After a wet winter, this is where freeze-thaw damage tends to show up first in the hardware.
The Slow Burns: Issues That Build Over Time
These four problems do not announce themselves with a creak or a sway. They develop quietly across seasons, and spring is the best time to catch them before summer use accelerates the damage.
4. Rot in the beams. Beams carry the joist load. If moisture has been sitting in beam-to-post connections over multiple winters, decay can hollow out the core while the surface still looks intact. Probe with a tool rather than relying on visual checks alone.
5. Water pooling on the deck surface. Standing water after a rain tells you the deck boards have warped, the structure has shifted, or both. Water that pools and sits accelerates rot in the surface boards and finds its way into the frame below. It also creates slip hazards that only get worse.
6. Soft spots underfoot. Walk every section of the deck surface slowly, putting weight through each board. Soft spots mean the board itself is compromised, or the joist beneath it is. Either way, that board will eventually become a trip hazard or worse.
7. Trapped moisture at wood framing joints. Anywhere two pieces of pressure-treated lumber sit against each other for long periods, moisture accumulates. Check where beams lap over posts, where joists meet the ledger, and anywhere debris has been packing against the frame. These are the places winter does its quiet work.
Wait, should I be inspecting the underside of my elevated deck myself?
If your deck is elevated and you can get underneath safely, go ahead and look. But some structural connections are not accessible without removing boards or getting into framing cavities. A professional evaluation covers what a homeowner’s walkthrough physically cannot reach.
The Remaining Five
8. Loose or missing fasteners. Go over the deck boards with your eyes and hands. Fasteners that have backed out create raised edges. Missing ones leave gaps that will widen. Structural screws that have corroded through are a hidden version of the same problem.
9. Deck railing stability. Grab each section firmly and push laterally. Building codes generally require railings to resist 200 pounds of lateral force. If your railing moves meaningfully when you push it, the post base connection or the attachment to the deck frame has failed.
10. Cracking in the deck boards. Tiny cracks are often cosmetic on newer boards. Large cracks, especially ones that run along the grain toward the ends of boards, are entry points for water. One more winter and a small crack becomes a split board.
11. Insect damage. Small holes in wood framing, particularly in untreated or older lumber, can indicate carpenter bee or carpenter ant activity. Look for frass (fine wood dust) near joists, beams, and posts. Insect damage from one season compounds fast in the next if untreated.
12. Surface wear and the overall deck surface condition. End of the list, but worth treating seriously on wood decks. A surface that has lost its protective coating holds moisture longer, which accelerates every other item on this list. Spring is the right time to clean, assess, and seal before summer UV and heat compound the wear.
FAQ
How often should a deck be professionally inspected? Once a year is the standard recommendation, with spring being the logical time. Any deck older than ten years, or one that has been through a particularly heavy snow season, benefits from a professional set of eyes rather than a homeowner walkthrough alone.
My deck passed a visual check but still feels bouncy. Is that a problem? Movement underfoot when the structure looks intact usually points to something in the framing rather than the surface boards. Joist hangers, beam connections, and post stability are the places to investigate before assuming everything is fine.
Does pressure-treated wood still need to be inspected? Pressure-treated lumber resists rot and insects longer than untreated wood, but it still degrades over time, especially at cut ends and connection points where the treatment does not fully penetrate. Treated lumber in a wet climate still needs regular inspection.
What is the screwdriver test? Press the tip of a screwdriver firmly into the wood at connection points, post bases, and beam ends. Sound, healthy wood resists the pressure. Wood that has rotted internally will give way under relatively light force. It is a simple, reliable way to find decay that looks fine on the surface.
Prefer to Skip All of This?
Twelve things to check, some of them requiring you to climb under the deck, probe wood with tools, push against railings, and assess hardware conditions most homeowners have never looked at before. That is a real afternoon of work, and it still may not catch everything a trained eye would.
If you would rather hand this off to someone who does it professionally, take a look at ourdeck repair services and see what the process looks like, then call us at (865) 801-4545 or message us here. We cover everything above and then some, and we will tell you honestly what needs fixing versus what can wait.
Two other pieces that may help you along the way: if you are curious about material choices that hold up better over the long term, our take on composite decking pros and cons is worth a read. And if you are in the Maryville area and want to know what building codes cover for deck construction and repair, our deck building codes guide for Maryville breaks it down clearly.