Deck & Balcony Rot Repair · CSLB #1060736
Commercial Deck & Balcony Rot Repair in California
We repair rot in decks, balconies, walkways, and stairs across the Bay Area, Central Valley, and Sacramento. Deck rot and balcony rot come from the same thing in different structures — water getting into the framing and staying there — and replacing the damaged timber is the visible half of this work. The half that decides whether you do it again is water — because new wood put back into the same wet conditions goes the same way as the old.
- CSLB #1060736 Licensed California contractor
- 9+ yrs Repairing rot in decks & balconies
- Water first Source corrected before the timber goes back
- Commercial & HOA Apartments, condominiums, HOAs & hotels
Where to start
Rot Repair by Structure
A deck loses section with posts still sharing the load; a cantilevered balcony has nothing behind the wall line. Pick the page for your structure.
CSLB #1060736SB 721 / SB 326 documentedCommercial, multifamily & HOA
01 Why it matters
A lasting repair fixes the water, not just the wood
Deck and balcony framing is built to get rained on and dry out again. It fails when water gets in and can’t leave — timber that stays wet for months at a time softens, loses section, and eventually stops carrying load. That single fact explains why so many repairs don’t last. New wood gets fitted into the same assembly, the water keeps arriving the same way, and the replacement starts down the same path as the member it replaced. Nothing fitted or applied to a member that water is still reaching changes that outcome.
Which means a lasting rot repair is a plumbing problem as much as a carpentry one. Find where the water is arriving — an unflashed ledger, a threshold draining toward the building, a coating that stopped working, a post base sitting in a puddle — and remove it. Replace the damaged wood. Give the framing a way to stay dry: drainage that leaves, joist tops that shed, ventilation where the assembly allows it. Do that and the repair holds.
Two honest qualifications on that. Drying out does not restore what has already been lost — timber that has given up section stays weak whether it’s wet or dry, which is why fixing the leak and repairing the framing are separate jobs. And the same logic explains why an identical detail produces identical results across a property: the buildings in these photographs have water-damaged framing on the upper balconies and the ground-floor decks alike, because the same water was arriving at both for the same reason.
Replacing wet wood and leaving the leak is paying for new timber to lose the same argument with a plumbing problem.
02 The D&B difference
What proper rot repair involves
The water is found before the wood is replaced
Every repair starts with where the moisture is arriving. New timber into unchanged conditions restarts the same clock, which is the single most common reason this work gets paid for twice.
Cut back past the visible edge
Water damage extends into timber that still looks and sounds sound. We cut back to material that resists a probe and keep going past it rather than stopping where the damage stops being obvious.
Structural repair, not filler
Consolidants and epoxy have legitimate uses on trim. They do not restore the capacity of a joist, a beam, or a post, and we won’t use them where structure carries people at height.
03 · Service Areas
Where We Work in California
Every city links to a dedicated local page — crews, recent projects and compliance details for that area.
Sacramento Metro
20 cities
East Bay
28 cities
North Bay
14 cities
Central Valley
13 cities
South Bay & Peninsula
27 cities
Don’t see your city? We likely still cover it — call (916) 848-2728.
04 How a project runs
How we repair deck rot and balcony rot
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01
Assessment
Structural assessment of joists, beams, ledgers, and post bases, with moisture readings, and openings where the critical section is enclosed.
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02
Water source
Where water is arriving at each affected point, because that determines what has to change beyond the timber.
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03
Scope & estimate
Written extent with a stated allowance for what opening up may add, and a clear statement where rebuilding is the better value.
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04
Support
Element taken out of service and shored where the loss of section requires it.
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05
Removal & replacement
Damaged wood cut back to sound material; joists, beams, rims, and posts replaced or sistered with rated connectors.
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06
Cause correction
Ledgers flashed, thresholds redetailed, joist tops taped, drainage corrected, waterproofing reinstated.
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07
Handover
Photographs of the work before and after, plus SB 721 / SB 326 compliance file material.
05 Scope
What we repair
Rot repair across decks, balconies, walkways, and stairs, from one CSLB-licensed crew.
- Structural assessment and moisture readings across the framing
- Water source traced at each affected point
- Openings where the critical section is enclosed behind stucco or soffit
- Temporary shoring and removal from service where section loss requires it
- Deck rot repair — joists, beams, rims, ledgers, posts, and stair stringers; dry rot deck repair included
- Balcony rot repair including cantilever joists at the wall line
- Dry rot on deck and balcony framing, and wet rot, cut back to sound material
- Members replaced or sistered with rated connectors
- Building framing repaired where water has reached it
- Ledger connections rebuilt and flashed per CBC 1604.8.1
- Joist tape and flashing over joist tops before surfaces go back
- Threshold and drainage detailing corrected so water leaves
- Waterproofing reinstated as a continuous system
- Honest assessment when the extent makes rebuilding the better value
- Documentation for the SB 721 / SB 326 compliance file
Built to current code: CBC 1604.8.1 ledger connections · ASCE 7 load criteria · rated connectors and structural fasteners
06 Investment
What rot repair costs
The cost to repair wood rot on a deck or balcony is quoted after an on-site assessment, and the estimate has to account for what can’t be seen until the framing is opened.
What drives the number
- How many members are affected, and whether they’re joists, beams, ledgers, or posts
- Where the damage sits — a ledger or a cantilever connection costs more than a joist mid-span because of what has to be supported while it’s out
- Whether members can be sistered or must be fully replaced
- Whether the building’s own framing has been reached
- The cause corrections needed at each location
- Temporary shoring and time out of service
- How many elements on the property share the same detail and condition
Why the number can move, and how we handle it: water damage often reaches beyond what can be seen before the framing is opened, and where the water has travelled along the framing it reaches further again. We state an allowance in the estimate rather than presenting it later as a change order — and where the assessment suggests the damage is likely extensive, we say so before you commit.
What the cause correction is worth: it’s usually a small fraction of the repair and it’s the entire difference between doing this once and doing it again. A quote that replaces timber without a line for flashing, thresholds, or drainage is quoting half a job at a competitive price.
Final pricing follows an on-site assessment. Request a free estimate — no obligation.
In the field
Rot repair detail
What the surfaces were covering, across decks and balconies alike.
07 Project example
A recent rot repair
A property had rot reported on two balconies and had already paid for a fix — a contractor had been out twice with a preservative and the timber had carried on deteriorating. The reason was simple once anyone looked: the water hadn’t gone anywhere. Thresholds drained toward the building rather than away, and the ledger detail behind them had never been flashed. Nothing applied to timber that was being wetted continuously was ever going to help. D&B opened up the elevation, found the same flashing detail on every element with the water damage at different stages, cut back to sound material, rebuilt and flashed the connections, redetailed the thresholds so water leaves, and reinstated the waterproofing.
We’d paid twice for a fix. Nobody had mentioned that the wood was still getting wet. Regional Property Manager · California apartment community
08 Case studies
Recent Projects, Documented
Real commercial properties — what the building needed, what we did, and what it delivered.
WaterproofingElevated Walkway & Balcony Waterproofing — 40-Unit Apartment Community, Rio LindaDry rot had opened holes straight through the walkway decks. We shored the spans, rebuilt the framing underneath,…View case study 
Deck RepairEntry Porch Deck Replacement Across a Townhome Row — PleasantonTwenty-four front-door decks rebuilt with air beneath them and planting pulled back from the edge — because these…View case study 
WaterproofingBalcony & Walkway Waterproofing — 12 Elevated Elements, Rio LindaThe coating still covered the middle of every walkway. It had given up at the edges, and the…View case study 
Deck RepairPrivate Deck & Guardrail Rebuild Across a Residential Community — Los AltosUnit-by-unit deck replacement where the guardrail was the real finding — railing posts rotted through at the rim,…View case study 
Balcony RepairSB 721 Balcony Ledger & Framing Rebuild — 72-Unit Apartment Community, Gilroy24 stacked balconies reframed where they attach to the building and where they rest on their posts —…View case study 
Deck ConstructionPatio Deck & Post Base Replacement Across a Bungalow Community — San RafaelDeck-by-deck replacement across a courtyard community, driven by the one detail that failed first — posts set straight…View case study 09 Client feedback
What property managers say
We’d paid twice for a fix. Nobody had mentioned that the wood was still getting wet.
They explained that drying the wood out doesn’t bring the strength back. That’s why we replaced rather than dried and hoped.
The same detail was wrong on every balcony on that elevation. Once they’d found it on one, they knew where to look on the rest.
10 FAQ
Rot repair questions
How do you repair wood rot on deck framing so it lasts?
By fixing the water as well as the wood. Framing that stays wet softens and loses strength; framing that can dry out between rains holds up. So a lasting wood rot repair on deck and balcony framing means finding where water is arriving — an unflashed ledger, a threshold draining the wrong way, a failed coating, a post base in standing water — removing it, replacing the damaged members, and giving the new timber a way to stay dry. Skip the water and the new wood goes the same way as the old.
Why do rot repairs come back?
Because the water was never dealt with. New timber, filler, or a fresh finish put into an assembly that is still being wetted buys nothing but the appearance of action. The repair holds when the source is corrected first — the flashing, threshold, drainage, or waterproofing that let the water in — and the damaged members are replaced into framing that can stay dry.
If the deck dries out, is the rot fixed?
No. Drying out doesn’t reverse the damage. Timber that has lost section has lost strength permanently — it stays weak whether wet or dry. So fixing the leak and repairing the framing are two separate jobs, and one doesn’t substitute for the other.
Why does dry rot deck damage often reach further than it looks?
Because water doesn’t stay where it enters. It runs along joists and beams and into connections, which is how soft, water-damaged wood turns up some distance from the original leak, in timber that can look dry. Damage close to a single, obvious leak is contained, and the repair boundary is straightforward once that leak is found; damage that has followed the water needs the framing opened wider. The practical difference is how far you cut.
What’s the cost to repair wood rot on deck framing?
It depends on how many members are affected and where. A joist mid-span is straightforward; a ledger, a cantilever connection, or a post is more, because the structure has to be supported while the member is out. On top of the timber comes correcting the cause, which is usually a small fraction of the repair and the whole difference between doing this once and doing it twice.
Can you repair deck joist rot without replacing the whole joist?
Often, by sistering — a new member fixed alongside the sound portion, spanning past the damage to bearings at both ends. It works where the damage is localised and the bearings are sound. It doesn’t work where the loss is at the bearing itself or where the member is compromised along its length, and in that case a sister just transfers the problem.
Is rot on a balcony different from rot on a deck?
Structurally, yes, and it’s worth knowing which you have. A deck losing section at the ledger still has posts and footings sharing the load. A cantilevered balcony carries everything at the line where its joists enter the wall, and there’s nothing behind it — the same loss of section is a repair item on one and a structural condition on the other. We have separate pages covering each in more detail.
Are you rot repair contractors in California?
We’re a CSLB-licensed contractor (#1060736) repairing rot across the Bay Area, Central Valley, and Sacramento, exclusively on commercial, multifamily, and HOA property. Assessment, shoring, structural repair, flashing, and the drainage corrections come from one crew — because separating them is exactly why rot repairs come back.
11 Start here
Find the water, then price the repair — free assessment
Tell us what you’re seeing: a soft board, a spongy step, a dark post base, a stain on a ceiling below. We’ll check the framing, find where the water is arriving, and give you a written scope with the timber and the cause both priced.
CSLB #1060736 · 9+ years · Insured & Bonded · Commercial, multifamily & HOA properties across the Bay Area, Central Valley & Sacramento