Concrete Resurface, Oakland, CA June 2025

This owner was converting a garage structure in Oakland into an office. The conversion involved adding windows and doing some demolition on the west-facing wall, and that left the concrete exterior of the wall patched, uneven, and scarred where the new openings had gone in. The fix was to resurface it: apply a new outer layer of dyed concrete over the old wall so it reads as one clean, uniform surface again.

Resurfacing starts with the bond. New concrete doesn’t stick well to old concrete on its own. Old surfaces are dense, dusty, and often slick, and a thin new layer applied straight over them can delaminate and peel away. So we used a bonding compound on the existing surface first, then applied the mortar over it. The bonding agent creates a tight connection between old and new, so the resurfacing layer behaves like part of the wall rather than a skin sitting on top of it.

Using a dyed mix means the color runs all the way through the new layer instead of sitting on the surface like paint. It won’t chip or peel to reveal gray underneath, and it weathers evenly over time.

The wall’s orientation mattered too. It faces west and takes a lot of direct sun from late morning on, spring through October. Heat and sun pull moisture out of fresh mortar quickly, and mortar that dries too fast can crack, crumble at the surface, or fail to bond fully. Timing the work around the sun and keeping the new layer from drying out too quickly gives it time to cure properly.

Otherwise, it was an unremarkable job, which is what you want from concrete work. The result is a clean, uniform wall that looks finished and fits the building’s new life as an office.