How often should a deck be inspected?

Annually is the general recommendation, and it’s worth doing your own version of it as a buyer regardless of when the last professional inspection happened.

Can a deck be repaired instead of replaced?

Often yes, if the issue is isolated, like a section of rotted boards or loose fasteners. A compromised ledger board connection is the exception, since it’s the structural point the entire deck hangs from.

Are older decks automatically unsafe?

No, age alone isn’t the issue, the ledger board connection and general wood condition are. An older deck built and maintained well can be safer than a newer one with a poorly attached ledger.

What is the lifespan of a wood deck?

Pressure-treated wood decks typically last 10 to 20 years depending on climate, drainage and maintenance. Composite decking lasts roughly 25 years on average, with premium lines warrantied up to 50, at a higher upfront cost.

How to Check a Deck, Patio or Porch Before Buying a House

Why do most deck collapses start at the ledger board?

Diagram comparing a deck ledger board correctly attached with lag bolts against one attached with nails only that is pulling away from the house — Bolted versus nailed. Nails alone tend to pull free under a deck's repeated load, which is why this one connection causes most collapses.

The ledger board is where the deck attaches to the house, carrying the weight of the entire structure at that single connection. An estimated 90% of deck collapses happen because that connection failed, not because of the posts or footings most people assume are the weak point.

This reframes the whole inspection. You don't need to evaluate an entire deck's structure to catch the highest-risk issue. You need to check one specific board where it meets the house, which takes a couple of minutes if you know to look for it.

How do you check a ledger board without tools?

Look at how it's fastened: bolts or heavy screws are correct, nails alone are not, since nails pull out over time under a deck's repeated load. Then probe the wood gently with a small screwdriver or the wood-rot probe from your toolkit, feeling for soft, spongy give instead of solid resistance.

What a deck finding actually means, and what it costs to address. Prices are national 2026 averages.
What you see	What it means	Typical cost	Verdict
Ledger board attached with nails only, no bolts or screws	The connection point in roughly 90% of deck collapses	Reattachment, varies by scope	walk
Ledger board feels soft or spongy when probed	Rot at the exact point that carries the deck’s structural load	Requires professional evaluation	walk
A visible gap where the ledger has pulled from the house	The connection is already failing, not just aging	Requires professional evaluation	walk
Rusted or loose fasteners elsewhere on the frame	General age or moisture exposure, less urgent than the ledger itself	$10 - $50/sq ft to address	price
Visible water staining on the siding above the ledger	Water has been getting behind the ledger connection	See the exterior guide	price

Also look for a gap where the ledger has visibly separated from the house's siding, rust on the fasteners you can see, and water staining on the siding directly above the connection. Any of these means water has likely been getting into that joint, which is exactly what causes the rot that leads to failure.

What other deck problems are worth checking?

Beyond the ledger: a spongy or bouncy feeling anywhere underfoot, visibly rotted or splintering boards, and rusted or missing fasteners on the railing and stairs. None of these carry the same collapse risk as the ledger, but they're real, boundable repair costs.

What does deck repair or replacement cost?

Repairs run $10 to $50 per square foot depending on scope and material. Full replacement runs $30 to $55 per square foot installed, with whole-project totals commonly landing between $5,000 and $25,000 depending on size and material, pressure-treated wood at the low end, premium composite or hardwood at the top.

Does a patio need the same scrutiny as a deck?

No, not in the same way. A ground-level patio doesn't have a ledger board connection carrying structural load the way an elevated deck does, so the collapse risk this page focuses on mostly doesn't apply. A patio is closer to a driveway in what actually matters: cracking, settling, and drainage, covered on the exterior guide.

Questions buyers ask

How often should a deck be inspected?: Annually is the general recommendation, and it’s worth doing your own version of it as a buyer regardless of when the last professional inspection happened.
Can a deck be repaired instead of replaced?: Often yes, if the issue is isolated, like a section of rotted boards or loose fasteners. A compromised ledger board connection is the exception, since it’s the structural point the entire deck hangs from.
Are older decks automatically unsafe?: No, age alone isn’t the issue, the ledger board connection and general wood condition are. An older deck built and maintained well can be safer than a newer one with a poorly attached ledger.
What is the lifespan of a wood deck?: Pressure-treated wood decks typically last 10 to 20 years depending on climate, drainage and maintenance. Composite decking lasts roughly 25 years on average, with premium lines warrantied up to 50, at a higher upfront cost.

Related checks

Ledger board safety statistic and inspection guidance: NADRA (North American Deck and Railing Association), Fine Homebuilding, Inside & Out Property Inspectors. Cost figures: Angi, Thumbtack, HomeGuide, Lawn Love, Premium Decking Supply 2026 guides. Figures are national averages current as of September 2026.

Deck, Patio and Porch Safety Checks