Deck Problems on a Home Inspection Report
Deck notes look minor on paper, but a few of them are about the deck staying attached to the house. The ledger connection, the railings and the stairs are the ones to take seriously. Loose boards and worn stain are maintenance. Know which is which before your inspection deadline.
I'm Wes Johnston, a Realtor with Trueblood Real Estate in Fishers. Before real estate I earned a construction engineering management degree from Purdue and spent about ten years designing custom homes and running their construction in Hamilton County. I'm not a home inspector, electrician, plumber or engineer, and this isn't a substitute for one. It's how I explain these findings to my own clients. Sources are linked as you go.
Short answer: most deck findings are maintenance, but a nailed or unflashed ledger, loose railings or weak stairs are real safety items. Have a deck builder or contractor evaluate the ledger and guards before your deadline. Repairs usually cost a few hundred to a few thousand dollars; a rotted ledger can mean rebuilding part of the deck.
- Typical cost to fix
- About $890 to $3,663 for a typical deck repair job (average $2,246). National figures.
- Who to call
- A licensed deck builder or general contractor. A structural engineer if the ledger or framing is questionable.
- Deal-breaker?
- Rarely. A deck in poor shape is a credit or a rebuild conversation, but don't use one with a failing ledger or loose railings until it's fixed.
Cost source: HomeAdvisor deck repair cost guide, updated June 20, 2026
- 01What does a deck note on a home inspection report mean?
- 02What is a deck ledger, and why does the flashing matter?
- 03Lag screws vs. through-bolts: what's the difference, and does it matter?
- 04What's wrong with my deck's joist hangers?
- 05How high does a deck railing have to be, and how far apart can balusters be?
- 06What about deck stairs, posts and footings?
- 07How much does it cost to fix deck problems?
- 08Should I ask the seller to fix the deck?
- 09I'm selling. Should I fix my deck before I list?
What does a deck note on a home inspection report mean?
Inspectors walk the deck, shake the railings, look underneath at the framing and footings, and check where it attaches to the house. Common wording:
- "Ledger flashing not observed" or "improper ledger attachment." The board bolted to the house isn't protected from water, or isn't fastened right.
- "Ledger appears to be nailed only." The one to take most seriously.
- "Joist hangers missing fasteners" or "improper fasteners in hangers."
- "Guardrail loose", "baluster spacing exceeds 4 inches" or "guard height less than 36 inches."
- "Stairs: uneven risers, no graspable handrail."
- "Wood rot observed at posts, joists or deck boards."
- "Recommend evaluation by a qualified deck contractor."
| Finding | Usually means | How worried to be |
|---|---|---|
| Worn finish, cupped or split boards | Normal weathering | Low. Maintenance |
| Loose boards, popped screws | Fasteners backing out | Low. Quick repair |
| Hanger fasteners missing or wrong | Joists not fully supported | Moderate. Contractor repair |
| Railing loose, gaps over 4 in., under 36 in. | Fall hazard by today's standards | Moderate to high. Fix before use |
| Rot at posts, joists or ledger | Water damage in the structure | High if it's the ledger |
| Ledger nailed only or no flashing | The deck's main connection is suspect | High. Evaluate before closing |
What is a deck ledger, and why does the flashing matter?
The ledger is the board fastened to the side of the house that the deck joists hang from. On an attached deck it carries the house end of every joist, and it's the connection that matters most. An article in the International Code Council's Building Safety Journal says ledgers "should be positively connected to the floor structure of the main building with bolts or lag screws, not nails," and that "one of the primary reasons for deck collapses is the failure of nail-only connections" (ICC Building Safety Journal, July 2020).
The American Wood Council's DCA 6 deck guide, the reference most inspectors and building departments use, calls for a ledger at least a 2x8 attached to the house's structural band joist or rim board, and prohibits attaching a ledger to brick veneer, hollow masonry, cantilevered floor overhangs or bay windows (DCA 6-2015 summary). A deck that can't attach to solid framing has to be freestanding, with its own posts and beam along the house.
Flashing is what keeps the ledger and the house's band joist dry. Without it, water runs down the wall, gets behind the ledger and rots the wood the bolts are holding onto. Deck inspector Bruce Barker warns that bolts or screws "may withdraw from water-damaged wood" (Professional Deck Builder, July 2019). Building departments publish their own flashing details; one current example layers a self-sealing membrane behind the ledger and calls for vinyl, copper or stainless flashing, with aluminum prohibited (Henrico County, VA deck flashing detail, March 2026). DCA 6 notes aluminum flashing must not be used with copper-based treated lumber (DCA 6 summary).
Lag screws vs. through-bolts: what's the difference, and does it matter?
Both are acceptable when they're the right size, spacing and installation. The ICC article cites the 2018 IRC's requirement for 1/2-inch bolts or lag screws per its ledger fastener table, and notes a 1/2-inch lag has a hex head 3/4 inch wide, which is how an inspector checks the size from below (ICC Building Safety Journal).
- Through-bolts go all the way through the ledger and the house band joist, with washers and a nut on the inside. They're the stronger, easier-to-verify connection, but they need access from inside (an unfinished basement or crawl space).
- Lag screws thread into the band joist from outside. They need correctly sized pilot holes and must extend all the way through the band joist, per the same ICC article. They're common where the inside is finished.
- Structural screws made for ledgers are also used, installed per the manufacturer's listing.
- Nails alone aren't acceptable. Barker says nailed ledgers are "prohibited by both DCA 6-15 and the IRC" and still turn up on new decks (Professional Deck Builder).
Newer decks also have lateral load connections, hardware that ties the deck joists back into the house floor so the deck can't pull away. DCA 6 shows hold-down devices rated at 1,500 pounds or more at two locations (DCA 6 summary); the IRC also allows four devices of at least 750 pounds (JLC on DCA 6). Older decks rarely have them, and adding them is usually a reasonable upgrade rather than a must.
On a new deck, the ledger is the first thing I'd look at. Siding comes off where the ledger goes, the band joist gets a membrane, the ledger goes on with bolts or lags in a staggered pattern, flashing goes over the top and laps under the house wrap, and the siding goes back on above it. It's not complicated, but every step has to happen in order, and it's easy to skip when the deck is added years after the house.
When I read a report, I look for three things together: how the ledger is fastened, whether flashing was seen, and whether there's rot or staining on the house band joist from the basement or crawl space side. Two out of three bad is a reason to get a deck contractor or engineer out before the deadline.
What's wrong with my deck's joist hangers?
Joist hangers are the metal brackets that hold each joist to the ledger or a beam. They only work with the fasteners the manufacturer specifies in the holes the manufacturer provides. Barker writes that hangers should have "a manufacturer-specified fastener in every hole," and that he often finds only two or three. Wrong fasteners are common too: roofing nails and drywall screws aren't approved for hangers (Professional Deck Builder).
Corrosion is the other note. Treated lumber is hard on steel, so hangers and fasteners need the right coating. Barker says significant red rust means the hardware should be replaced. A deck contractor can usually re-fasten or replace hangers one joist at a time without tearing up the deck.
How high does a deck railing have to be, and how far apart can balusters be?
Under the 2018 International Residential Code, which the 2020 Indiana Residential Code is based on (ICC), these are the main numbers (summarized in a 2018 IRC stair and guard handout from Knox County, TN):
| Item | 2018 IRC requirement |
|---|---|
| When a guard is required | Walking surface more than 30 in. above the floor or grade below |
| Guard height on the deck | 36 in. minimum (R312.1) |
| Guard height on open stair sides | 34 in. minimum, from the tread nosing |
| Openings in the guard | Must not pass a 4-in. sphere (R312.1.3) |
| Triangle under a stair guard | Must not pass a 6-in. sphere |
| Handrail height on stairs | 34 to 38 in. (R311.7.8) |
Older decks were often built to looser rules, so a 1980s deck with 6-inch baluster gaps or a 32-inch rail isn't necessarily "illegal." But inspectors write to current standards, and the reason is simple: these rules are about people falling. A railing that moves when you push on it matters more than one that's an inch short. Guard posts need a solid bolted connection to the framing, not just nails, and DCA 6 has specific guard post details for that (JLC on DCA 6).
What about deck stairs, posts and footings?
Stairs get a close look too. The 2018 IRC limits risers to 7 3/4 inches and calls for treads at least 10 inches deep, with risers that don't vary more than a little from step to step (Knox County 2018 IRC handout). DCA 6 adds limits on stringer spans, 6 feet for cut stringers (DCA 6 summary).
Underneath, inspectors look for posts sitting on the ground or on loose blocks, posts rotting at grade, and footings that have heaved or settled. DCA 6 calls for footings on undisturbed soil at least 12 inches below grade or below the local frost line, whichever is deeper (DCA 6 summary). Central Indiana's freeze-thaw cycles and clay soils punish shallow footings, so ask your local building department for the frost depth if a footing has to be redone.
Rot is a matter of age and water. InterNACHI estimates deck planks last about 15 years and structural deck wood 10 to 30 years (InterNACHI life expectancy chart). Push a screwdriver into suspect wood. If it sinks in easily on a post, joist or the ledger, that's structure, not maintenance. Damaged wood can also be insect damage, which the termite page covers.
How much does it cost to fix deck problems?
National figures. Each row names its source, because the two guides price different things:
| Repair | Typical cost | Source |
|---|---|---|
| Deck repair job (overall) | $890 to $3,663, average $2,246 | HomeAdvisor, updated June 20, 2026 |
| Railing repairs | $500 to $4,000 | HomeAdvisor |
| Board replacement | $500 to $4,000 | HomeAdvisor |
| Rotted wood repair | $200 to $500 | HomeAdvisor |
| Anchor loose stair treads | $15 to $40 per step | HomeAdvisor |
| Repair or replace a joist | $100 to $300 to repair; $150 to $350 to replace, per joist | Fixr, updated Jan. 31, 2025 |
| Replace a post | $200 to $400 per post | Fixr |
| Replace a footing | $300 to $400 per footing | Fixr |
| Deck inspection | $25 to $200 | Fixr |
Sources: HomeAdvisor deck repair cost guide, updated June 20, 2026; Fixr deck repair cost guide, updated January 31, 2025 (used only for items HomeAdvisor doesn't price).
HomeAdvisor's page labels its overall range as deck replacement in one place and as fixing a deck in another, so treat it as a typical repair job, not a full rebuild. Neither guide prices a ledger replacement, because it depends on how much of the deck has to come apart and whether the house band joist is damaged too. That's the item to get a written contractor estimate for before your deadline.
Should I ask the seller to fix the deck?
For safety items, yes. Loose railings, missing hanger fasteners, a nailed ledger or stairs with no handrail are fair to ask for. Write it specifically: "Seller to have a licensed contractor secure all guardrails, install manufacturer-specified fasteners in all joist hangers, and fasten the ledger with bolts or lag screws per DCA 6, with invoice."
If the deck is old, rotting or would need a ledger rebuild, a credit is usually better than a seller-managed repair. A deck is often a candidate for replacement rather than a patch, and you'll want to choose the design and the builder. Ask whether the deck was permitted; your city or county building department may have the record.
Before the deadline, get a deck contractor out. If the ledger or framing looks questionable, a structural engineer's letter is worth it. For how the timeline works, see the inspection period in Indiana. Rot on the house side of the ledger can also show up as a stain in the basement; the wet basement page covers water coming in from outside.
I'm selling. Should I fix my deck before I list?
Fix the safety items: tighten or replace loose railings, fill the empty hanger holes, add a handrail on the stairs, and replace any rotted boards someone could step through. Those are inexpensive, and they're exactly what buyers' inspectors write up. A fresh cleaning and stain helps the photos too.
If you know the ledger isn't flashed or the deck is near the end of its life, it's usually better to disclose it and price for it than to rush a partial fix. Ask me how it fits on the Indiana seller's disclosure, and see what to fix before selling for the rest of the list.
Why a Realtor Who Built Houses Reads Reports Differently
A home inspection report runs dozens of pages, and almost every item ends with "recommend evaluation by a qualified professional." That wording is there for the inspector's protection. It doesn't tell you which items are a quick fix and which ones change the deal.
I spent about ten years designing houses and running their construction before I sold them. When my clients get their report, we go through it together and sort it into what to ask for, what to take as a credit, what to just fix yourself later, and what needs a specialist before the inspection deadline. If you're buying or selling in central Indiana, I'm happy to do the same for you.
Construction engineer turned Realtor. Straight answers before you sign.
Send Me the Page That Worries You
Tell me the address and the finding. I'll tell you how serious it looks from a builder's point of view and how it usually gets handled in a deal.
Send a MessageWhat's Your Home Worth?
Selling an older home? Start with a realistic price based on recent local sales.
Have a Deck Question?
Send the address and the line from the report. I'll get back to you with how serious it looks and how it usually gets handled.
General guidance from a Realtor with a construction background. Hire the licensed trade for the diagnosis and the fix.
General information from a Realtor with a construction background, not engineering, code or legal advice. Cost ranges are national figures from HomeAdvisor (updated June 2026) and, for joists, posts, footings and inspections, Fixr (updated January 2025); Indianapolis-area quotes vary. Code numbers are from the 2018 IRC and AWC's DCA 6; your local building department enforces its own adopted code. Have a licensed contractor evaluate and repair the deck.