Deck Replacement Costs: Resurface or Rebuild

Two jobs, one word

When owners say “deck replacement” they usually mean one of two projects, and the cost difference between them is large.

Resurfacing keeps the structure and replaces the surface. New decking, usually new railings, often new stairs. The frame, posts and footings stay because they have real service life left.

Full replacement takes the structure out too — frame, posts, and footings where they are inadequate or badly placed.

Working out which one you need takes ten minutes under the deck with a flashlight and a screwdriver. Any contractor quoting without doing that is guessing, and the guess will be in their favour.

The ledger decides it more often than anything else

The ledger is the board bolted to the house carrying one entire side of the deck. Behind it there should be flashing directing water out and away.

On a great many decks built more than a decade or two ago, there is not. Without flashing, every rain runs down the siding, behind the ledger, and sits against the rim joist of the house. Nothing is visible from above. The deck feels normal. Then a joist hanger pulls through, or a probe goes into the rim joist like soft cheese.

This is the defect that collapses decks. It is also the one that most often turns a planned resurface into a full replacement — and occasionally into a building repair before any deck work can begin.

Check it first. Everything else follows from the answer.

What drives the cost of each route

Resurfacing

• Deck area — boards are priced by the square foot
• Material — treated timber versus composite, and within composite, capped versus uncapped
• Railings — often the larger share of a resurface, especially if upgrading to cable or metal
• Stairs — treads, stringers and geometry, frequently needing updating to current requirements
• Joist spacing — if you are moving to composite and the existing spacing is too wide, joists have to be sistered in. This is a common surprise and worth establishing before you commit to a material.

Full replacement

Everything above, plus:

• Demolition and disposal of the existing structure
• Footings — depth, size and placement to current requirements, which older decks frequently do not meet
• Framing — the bulk of the structural labour
• Ledger and flashing done properly, including any repair to the house structure behind it
• Permitting and inspections

The saving from replacing rather than building new from scratch is real but smaller than people expect. Most of the cost on either job is in the frame, the footings and the labour, not the boards.

Code upgrades you should budget for

A deck being substantially rebuilt generally has to meet current requirements. Older decks commonly fall short on:

• Railing height — standards have risen over the years
• Baluster spacing — maximum gaps have tightened
• Stair geometry — rise, run and handrail requirements
• Footing depth and size
• Ledger attachment method — fastener type, spacing and pattern

None of these are optional, and all are better in the quote than discovered at inspection.

The cheapest time to change anything

Everything that is expensive to change on a finished deck is inexpensive during a replacement.

Making it bigger. Adding a second level to follow the fall of the ground. Moving the stairs to land somewhere more useful. Switching to a railing that does not block the view. Changing the surface material. Adding a roofed section.

All of it shares the demolition, mobilisation and finishing work you are already paying for. If there is anything about the current deck you dislike, this is the conversation in which to say so — not after the new boards are down.

Where the money is well spent

If the budget is constrained:

• Do not economise on the ledger, flashing, footings or hardware. These are the parts that fail dangerously.
• Do consider resurfacing if the frame genuinely has years left. It is legitimate and it is good value.
• Do spend on the railing if the deck has a view worth seeing.
• Do think about surface temperature before colour — it decides whether the deck gets used in July.

More detail: deck replacement and deck repair.