What yards hire under this name is a concrete grinder, not a sander: a walk-behind or hand-held machine turning diamond discs, at roughly $100 to $250 a day for a single-head walk-behind and $60 to $150 for a hand-held. The line most people miss is the dust extraction. Dry-grinding concrete throws respirable silica, and the HEPA vacuum that controls it is a separate hire of about $60 to $120 a day.
Grinder, polisher or scarifier
A grinder with diamond discs takes down high spots, removes thin coatings and opens the surface. A polisher runs finer resin pads over several passes for a finished floor. A scarifier cuts far more aggressively with steel cutters and leaves a rough profile. Ask for the machine that matches the finish you want, because the three are not interchangeable.
The disc decides how fast it works
Diamond segment hardness runs opposite to the concrete: a soft bond for hard slabs, a hard bond for soft or green concrete. Grit runs from about 16 for removal to 400 and beyond for polish. Discs are consumables and are billed on use, so tell the counter what you are removing and let them match the bond rather than guessing.
Dust control is part of the hire
Grinding concrete dry generates respirable crystalline silica, and the recognised control is a shroud on the machine feeding a HEPA-filtered vacuum sized to the tool. Hire the two together. A shop vacuum without a HEPA filter recirculates the fine fraction, which is the part that matters, and clogs within minutes on a real floor.
Single head, three head, and time on the floor
A single-head walk-behind covers a garage or a small room and is what most counters stock. A three-head planetary machine costs two to three times more per day and covers ground several times faster, so on anything over a few hundred square feet the bigger machine is usually cheaper in total once labour is counted.
Questions people ask about concrete sander rental
Can I use a concrete grinder indoors?
Yes, with a HEPA vacuum attached and the room sealed off from the rest of the building. Electric machines avoid the exhaust problem entirely. Check the amperage draw, because a large grinder on a domestic circuit will trip it repeatedly.
Are diamond discs included in the rental?
Usually not. Discs are consumables, hired or sold separately and billed on wear when the machine comes back. Ask what a set costs before you take the machine, because on an aggressive removal job the discs can approach the hire rate.
How much floor can one machine do in a day?
A single-head walk-behind covers roughly 300 to 600 square feet a day on a removal pass, far more on a light polish. A three-head machine multiplies that. Multiple passes at different grits multiply the time in the same way, so plan by passes rather than by area.