Found something?
Photograph it and check it here. You get a plain-language read of what is visible in the picture, keyed to the six checks above. Anything it flags, GRP will look at in person at no charge. If it turns out to be nothing, we would rather tell you that than have you worry about it all summer.
Free, no obligation. Serving New Hope, Doylestown and surrounding Bucks County communities.
Deck safety
Signs your deck needs repair
Six checks, ten minutes, and a screwdriver. This is the walk we take when we first look at a deck, written so you can do the visible half of it yourself.
Most decks that need work do not look like they need work. The wood at eye level weathers evenly and honestly, while the parts that actually carry the load sit underneath in the shade, wet for longer than anything else. That is where you are going to look.
Before you start
- A flashlight. Most of what matters is in shade, under the deck.
- A screwdriver or an awl. Anything with a point you can press into wood.
- Ten minutes, and shoes you do not mind getting dirty.
- Stop using the deck
Check 1 of 6
Where the deck meets the house
Start here. Look along the joint where the deck framing meets the house wall. The board doing that job is the ledger. Check it from underneath if you can get there, and from above where the decking meets the siding.
What you are looking for
- A gap opening between the deck framing and the house wall
- The deck sitting visibly lower at the house than it does at the outer posts
- Rust stains, or streaking down the siding below the joint
- Nail heads backing out, or bolt heads you can turn by hand
- Softness or dark staining in the siding or trim directly above the joint
This one connection carries the end of the deck that people stand closest to, and it is the connection that fails most often. It is also the failure that gives the least warning: a ledger lets go all at once. If you check one thing on this list, check this.
What this check cannot tell you: You cannot see how the ledger is actually fastened, or whether it was flashed to keep water out, without pulling siding. A joint that looks clean from outside can still be rotting behind it.
Keep people off it until someone has looked at it. What this usually takes to put right
- Stop using the deck
Check 2 of 6
The bottom of the posts
Get underneath with the flashlight. Look at the last six inches of every post where it meets concrete or ground, then press the screwdriver into the wood at that point. Sound wood resists, and the tip barely marks it. Rotten wood takes the tip like firm cheese.
What you are looking for
- The screwdriver sinking in easily, or coming out with wet fibres on it
- Posts sitting directly on soil, or in standing water after rain
- Dark, spongy or crumbling wood in the bottom few inches
- A post you can rock slightly by hand
- Soil or mulch banked up against the post
Water travels down a post and stops at the bottom, so the base stays wet longest and rots first. The rot works upward from the end grain, which means the wood at eye level can look perfect while the part actually carrying the load has gone.
What this check cannot tell you: The footing below is out of sight entirely. A sound post can still be sitting on a footing that was undersized, never poured, or has shifted with frost.
Keep people off it until someone has looked at it. What this usually takes to put right
- Stop using the deck
Check 3 of 6
The stairs
Look at the stringers, the sawtooth boards the treads sit on, from the side and from underneath. Check where each tread notch is cut, and check the bottom of the stringers where they land.
What you are looking for
- Cracks running out from the inside corner of a tread notch
- A stringer that has split along its length
- Treads that flex or tip underfoot, or that have pulled loose at one end
- Rot where the stringers land on concrete or ground
- Steps that are noticeably different heights from one another
Cutting the notches removes most of a stringer, so what carries the stairs is a narrow strip of wood along the back edge. Once that cracks there is very little holding the step, and stair falls hurt people far more reliably than deck falls do.
What this check cannot tell you: A crack can run inside the board where you cannot see it. Stairs that feel firm today are worth rechecking after a hard winter.
Keep people off it until someone has looked at it. What this usually takes to put right
- Get it looked at
Check 4 of 6
The railings
Push each section. Do not lean on it. Use a hand at chest height and push out and down with steady pressure. Work along the whole run, and pay attention to the corner posts and to any post next to the stairs.
What you are looking for
- A section that moves, creaks or springs back
- Visible gaps opening where a post meets the deck framing
- Rot at the base of a railing post, in the same place you checked the main posts
- Balusters that spin, rattle or are missing
- Gaps wide enough for a small child to get through
A railing is only doing its job at the moment somebody falls against it, which is the worst possible time to find out it was loose. Most loose railings come loose where the post attaches to the frame, so that is the place to test.
What this check cannot tell you: Push, do not lean. If a railing is going to fail, the point of this check is to find that out with your hand.
It will not improve on its own. What this usually takes to put right
- Get it looked at
Check 5 of 6
The deck surface
Walk the whole deck slowly, in a grid, feeling for anything that gives underfoot. Stop at anything that feels soft and press the screwdriver into it. Pay extra attention along the house, around posts, and anywhere a planter or a grill has sat for years.
What you are looking for
- Boards that flex, sponge or sound hollow underfoot
- A bouncy feeling that spreads across a whole area
- Dark staining, cupping or splitting concentrated in one patch
- Wood that stays damp for days after everything else has dried
- Mushrooms or fungus growing in or under the deck
A soft board is usually a symptom. It marks where water has been sitting, which means the joist underneath has been getting the same water for the same number of years. Bounce across a whole area points at the framing below the boards.
What this check cannot tell you: Boards can be replaced; the framing under them is what decides whether that is worth doing. From above you cannot tell which one you are dealing with.
It will not improve on its own. What this usually takes to put right
- Get it looked at
Check 6 of 6
The hardware
Back underneath with the flashlight. Look at the metal: joist hangers, bolts, screws, the brackets at the posts. Judge the condition of the metal itself, as well as whether things are tight.
What you are looking for
- Rust streaking, flaking, or orange staining running down the wood below a fastener
- Joist hangers with empty nail holes, or nails that have backed out
- Bolts that turn freely, or nuts you can move by hand
- Metal that has thinned, pitted or corroded through
- Deck boards held down with nails, where screws belong
Hardware is the part of a deck people never think about and the part that decides how much load the wood can actually carry. Corroded fasteners can look like surface rust and have lost real section underneath.
What this check cannot tell you: Some corrosion happens inside the joint, between the metal and the wood, where none of it shows. Heavy rust staining on sound-looking hardware is worth taking seriously.
It will not improve on its own. What this usually takes to put right
Found nothing? That is good news about the half you can see.
Everything on this list is visible from the surface. The failures that put decks in the news happen out of sight: a ledger rotting behind siding, a footing that was never poured deep enough, corrosion inside a joint. A clean walkthrough tells you nothing obvious is wrong, which is good news. Whether the structure is sound is a separate question, and answering it takes someone under the deck.
This page is a homeowner's walkthrough, and it stops where an inspection starts. If your deck is more than about fifteen years old, if you have owned it less than a year, or if you are planning to have a crowd on it this summer, that is reason enough to have it looked at properly.
Questions homeowners ask about deck safety
Ready to transform your outdoor space?
Every project deserves quality, reliability and craftsmanship. If you’re ready to bring new life to your deck or outdoor space, let’s start with a free, no-obligation quote.