The ledger is the board that fastens the deck frame to your house, and it is the single most common point of failure on a deck. Everything the deck carries at that edge, including people standing near the door, transfers through that connection into your house framing. When it lets go, it usually goes all at once and with no warning from above. So this is where you look first, before you think about a single deck board.
Get underneath and look at the top edge of the ledger where it meets the wall. You are checking for flashing, a metal or membrane detail that pushes water out over the siding so nothing gets behind the board and into the rim joist. If you see the ledger tight to the siding with nothing above it, water has been going somewhere. Press a screwdriver into the wood at the top edge and at the ends. Soft, punky, or dark wood there is a serious finding worth a professional look right away.
Follow the posts down. In Utah, footings must reach below the frost line, because soil that freezes expands and lifts whatever sits on it. You cannot see how deep a footing goes from the yard, but you can read its behavior. Posts leaning out of plumb, a deck that has developed a slope it did not used to have, stairs pulling away from the deck, or gaps that open in winter and close in summer all point at footings that are moving.
Then look at where the wood meets the concrete or the ground. Posts should sit on a base that keeps them up out of standing water, not buried in soil or resting directly in a puddle-prone spot. Wood in contact with wet earth will rot from the bottom, and by the time it shows at eye level the damage has been underway for years. While you are down there, check that each post actually bears on something under it rather than being fastened alongside a beam and asked to hold by fasteners alone.
Look closely at the ledger connection and at the joist connections. Nails at the ledger are one of the most common findings on older decks, and they are not what that connection needs. Structural fasteners, meaning through-bolts or approved structural screws installed in a proper pattern, are what carry that load. If you see a row of nail heads, or fasteners spaced randomly wherever someone could reach, treat it as a reason to get a contractor underneath the deck.
Check the metal too. Joist hangers should be full of fasteners in every hole, not two nails in the corners, and the connectors themselves should not be rusted through or streaking down the wood. Corrosion at connectors often means water has been running past them regularly, which is a clue about drainage as much as it is about metal. Anything that has clearly been mixed and matched over the years, with several different fastener types in one connection, deserves attention.
Grab the guard and lean into it the way a person would at a crowded barbecue. It should not move. A guard that flexes at the base is telling you the posts are attached to the rim rather than blocked and fastened into the framing, and that is a framing repair rather than a matter of tightening bolts. Check every post around the deck, not just one, and pay extra attention at corners and at the top of the stairs where people put their weight without looking.
Then look at the gaps in the infill and at the height of the guard itself. Requirements for both have changed over the years and older decks often fall short, especially decks that sit well above grade where a fall would carry farther. Specific dimensions vary by jurisdiction, so rather than measuring against a number you found online, note what you have and ask. On the stairs, check that every riser is the same height, that stringers are solid, that the bottom step lands on something stable, and that there is a handrail your hand can close around.
Walk across the middle of the deck at a normal pace and pay attention to what the floor does. If it bounces, that is a joist span or beam issue, not a decking issue. It means the framing is spanning farther than it should, or the beam under it lacks support, and no amount of new surface boards will change it. Bounce alone is not a collapse warning, but it is a reliable sign the deck was built without much margin, which makes everything else on this list more worth checking.
Rot works from the outside in and hides in specific places. Cut ends soak up water, so look at the ends of joists, the tops of posts, and anywhere a board was trimmed on site. Look where framing contacts the house, where the deck meets planters or a hot tub, and under anything that has been sitting in one spot for years. Probe with a screwdriver rather than trusting your eyes. Sound wood resists. Wood that takes the tip easily is done, no matter how good the stain looks.
Everything above is homeowner work. You can find a missing flashing, a wobbling guard, a bouncing floor, a soft joist end, and a post that has moved, and finding any of those is genuinely useful. What you cannot do from the yard is confirm what your deck is required to meet, because adopted codes and their amendments vary by city and county across the Wasatch Front, and what was approved when the deck was built may not be what applies now.
So make the call. Your city building department will tell you what applies at your address, what triggers a permit, and what an inspection will look at, and they answer these questions all the time. Then, if what you found is structural, get a deck contractor underneath it before the next time you fill that deck with people. Call us at 801-644-9000 and we will connect you with someone along the Wasatch Front who starts at the ledger and the footings rather than at the surface.
Give it a real look every year, ideally in spring after the freeze-thaw season has done its work, and get a professional underneath if anything you found involves the ledger, the footings, or the framing. Decks age from the inside out, so a yearly look at the underside is worth more than a decade of watching the surface.
The ledger connection and its flashing. It is the most common point of failure, it fails suddenly, and it is invisible from the top of the deck. If you only crawl under your deck once, do it to look at how the frame attaches to the house and whether water has been getting behind that board.
Not necessarily. An inspection confirms the deck met requirements on the day it was built, not that it has held up since. Fasteners corrode, footings move, wood takes on water, and guard requirements have tightened over the years. Age and Utah weather both work on a deck continuously, whatever the original approval said.
New build, repair, cover, railings, or resurfacing, tell us which and we will take it from there.