When we had our garage floor done, the sub contracted bastards hid an insulation panel under the surface, likely as they ran out of material.
Our builder came back 2 years later to rectify, and his team achieved a brilliant finish. The only issue is there is about 1sqft they missed, it's probably not worth me getting the builder out, so I'd like to cut this chunk out and reconcrete it myself.
I've mixed plenty of concrete in my time, but achieving such a smooth finish I'm unsure of....
Pics attached, I filled a chunk with silicone just to stop water getting in. Other pic is what the builder achieved, and I painted over it.
Any recommendations??