Case Study · Ground-level patios · CSLB #1060736
Concrete Patio to Composite Deck Conversion — Ground-Floor Units at a Mixed-Use Property, Oakland
16 worn, weed-filled concrete patios turned into low composite decks built over the existing concrete — kept below the door sills and sloped so water runs away from the building.
Deck ConstructionProject facts
- Location
- Oakland, CA
- Service
- Patio Building
- Property
- Mixed-use property — ground-floor retail plus two residential buildings with private ground-floor patios
- Units
- 64
- Client
- Property owner / management company
- Scope
- 16 concrete patios converted to composite decks · low framing over the existing concrete · positive slope away from the building · metal edge trim at the lawn · worn privacy fencing replaced where needed
- Timeline
- 5 weeks · residents in place
- Completed
- Q3 2026
- Budget range
- $95k–$130k
01 The situation
The challenge
The private patios behind the ground-floor units were the original concrete — square pavers at one building, poured slabs at the other. The pavers had stained and loosened, the slabs had cracked, weeds and grass grew through every joint, and the surface had stained dark where water sat after rain. Residents had stopped using them, and the patios were the first thing a prospective tenant saw through the sliding doors.
Breaking out and repouring the concrete would have meant jackhammers outside occupied units, debris hauled through the buildings and weeks of curing time. The patios also sit directly against the sliding doors, so any new surface had to stay below the door sills, and it could not send water toward the building the way the old concrete did.
02 Execution
What we did
The new decks went on top of the old concrete instead of replacing it:
Cleared the weeds and debris, measured each patio against its door sill, and checked the slope so the new deck would drain away from the building
Built low framing over the existing concrete, shimmed to set a positive slope away from the walls while keeping the finished surface below every door sill
Installed composite decking across each patio, extending past the old concrete edge where the layout called for it
Finished the lawn side with metal edge trim, so the deck edge stays clean and the grass and mulch stay off the boards, and replaced the worn privacy fencing between units where it had failed
03 Outcome
The result
Every ground-floor unit now opens onto a level composite deck instead of cracked concrete, without breaking out the old concrete and with no concrete curing time. The decks sit below the door sills and slope away from the building, so rain moves off the patio rather than toward the doors. The composite surface also removes the weeding between joints that the old concrete needed.
Results at a glance
- 16 worn concrete patios converted to composite decks
- Built over the existing concrete — no breaking out or new concrete
- Finished surface below every door sill, sloped away from the building
- Metal edge trim at the lawn on every patio
What the client received
- Decking manufacturer's warranty and our workmanship warranty
- Door-sill and slope measurements recorded for each patio
- One decking color and edge detail across both buildings
- Care guide for the composite surface
Transformation
Before & After
Paver patio
Slab patio and fence
“We expected jackhammers outside every unit. They built the decks right over the old concrete, kept them under the door sills, and residents started using their patios again.”
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