What we look at under an old deck
The decision is made underneath, not on top: the frame tells us more than the boards do.
When a repair is money wasted
- White dry rot on the frameThe first thing we look for under the deck. Once it is in the framing, patching one board just moves the problem along.
- A 15 to 20 year old frame in untreated lumberFraming that was never pressure-treated has done its time by then. The replacement goes in on a pressure-treated frame so the problem does not come back.
- Rotten or termite-eaten beams, posts or joistsWhen the parts that carry the load are gone, there is nothing left worth saving under the boards.
- A frame built without the hardwareNo metal connectors between posts and beams, no joist hangers, joists too small for their span or set too far apart. A frame like that is held by a few nails. In an earthquake it folds like a house of cards.
- A deck that movesIt wobbles when you walk across it, the boards are cracked and worn, nails stand up out of the surface. Joists set too far apart wear the boards out early.
When a repair is the right call
- The deck is nearly new or in great shapeSomething got dropped, a board got damaged, one warped and needs screwing back down. That is a local repair.
- It only needs maintenanceWash and stain, or wash, sand and stain. See what that costs in our refinishing cost guide.
Why patching an old deck rarely pays
Fix one soft spot on a tired frame and in two or three years the same thing shows up somewhere else. Three or four rounds of that and the owner has spent about what a new deck costs, and still has an old one. A new deck lasts about 30 years.
Rot shows up first where the wood is closest to the ground, and in joists that were never pressure-treated.
The middle option: new boards on a sound frame
When the frame is pressure-treated and in good shape but the boards are worn out, we do not tear everything down.
- We keep the pressure-treated frame if it is soundMost of it stays. Broken or weak pieces are replaced.
- We add joists where composite needs themComposite boards want joists closer together than an old wood deck had, so we fill in the gaps.
- New boards go on topThe client saves the cost of a new frame.
What repair and replacement cost
Replacement is priced like a new deck plus about $5 per sq ft for taking the old one out and hauling it away. On level ground that is $45 to $60 per sq ft in pressure-treated wood, $48 to $60 in redwood and $55 to $80 in composite. Elevated and hillside decks cost more.
Repair we do not price from a table. We open up what needs opening and give you the number in writing.
Price a replacementOld deck, no budget yet?
If it is stable and nothing that carries the load is rotten, you can leave it alone for now and put the money toward a replacement. Patching an old frame piece by piece is money that does not come back. If it was built without connectors and joist hangers, have it looked at first.
Questions people actually ask
Should I repair or replace my deck?
Replace it if the frame has dry rot, if it is 15 to 20 years old and built from untreated lumber, if the posts, beams or joists are rotten or termite-eaten, or if it was built without metal connectors and joist hangers. Repair it if it is nearly new and the damage is local.
How long does a deck last?
A new deck built on a pressure-treated frame lasts about 30 years. An untreated frame is usually done at 15 to 20.
Can you put new boards on an old deck frame?
Yes, if the frame is pressure-treated and sound. We replace the weak pieces, add joists if the new boards are composite, and deck over it.
How much does deck replacement cost in the Bay Area?
In our calculator, replacing a deck costs the new-deck rate plus about $5 per sq ft for demolition and haul-away: pressure-treated $45 to $60, redwood $48 to $60, composite $55 to $80 per sq ft on level ground.
How much does deck repair cost?
We do not price repairs from a table: two decks with the same symptom can need an afternoon or a new frame. We open up what needs opening and give you the number in writing. Text us photos first and we will tell you what we expect to find.
Does deck repair need a permit?
Ordinary repairs need no application under CRC R105.2.2, and swapping worn boards is usually treated that way. Replacing joists, beams or posts is not an ordinary repair. Your building department makes the call.
My deck is old but I cannot afford a replacement. Should I patch it?
If it is stable and nothing that carries the load is rotten, leave it alone for now and put the money toward a replacement. Patching an old frame piece by piece costs about as much in the end and still leaves you with an old frame. If it was built without connectors and joist hangers, have it looked at first.