Finisher slang for the final machine passes of a hard-trowel finish, where the blades are tilted steeply and run until the surface takes on a dense, burnished shine. Burned slabs resist wear and suit warehouses, garages and shops where the floor stays exposed. It only works on concrete without entrained air, and burning too late or too hard leaves dark burn marks.
Burn that slab before you go home, the GC wants it slick for the forklift traffic Monday.
Burning an air-entrained slab seals air and bleed water under a tight skin, the classic recipe for delamination.
Also heard as
- burnish
- hard trowel
- burn it in
- burnished finish
Related terms
Power trowel
A gas or electric machine with rotating blades that floats and trowels large concrete slabs.
Pan
A round steel float disc clipped onto a power trowel's blades for the first, flattening machine passes.
Air entrainment
Deliberately building billions of microscopic air bubbles into concrete so it survives freezing and thawing.
Delamination
A surface layer that has split away from the concrete below it, found by the hollow sound it makes when tapped.