Project example: a 4-bay auto shop floor in the Bayfront and Bay Boulevard area — what it involves and what it costs

The scenario

Think of a small repair shop in an industrial building on or near Bay Boulevard, a few blocks from the water. It has four bays with a roll-up door each, two lifts and an oil-stained, patched concrete floor. A single crack runs across the second bay, and the oldest part of the slab is dark with years of drips.

Two problems get the installer's attention before the color is discussed. The first is oil. Oil sits in the pores of concrete, and a primer cannot soak into oiled concrete, so the stained zones are degreased and ground again. The second is dampness. A building close to the bay can have a slab that stays cool and damp in the marine layer of a June morning, so a moisture reading comes first, and a vapor-barrier primer goes on the bays where the readings are high. Near the coast, damp air slows curing and can raise slab moisture; installers watch the dew point and the slab temperature before coating.

The owner cannot close all four bays at once. The plan is two bays at a time: the crew coats the first pair, the shop works out of the other pair, then they swap.

The shop owner also keeps a small parts room behind bay four. It needs the same prep but no lift base, and the installer suggests the floor there is done last so parts can be shifted once.

The starting conditions at a glance:

• Footprint: about 2,400 square feet, four bays
• Slab: oil-soaked, damp in places, cracks across one bay
• Loads: hot tires, brake fluid, cleaner and jack stands
• System: solid color epoxy with grit
• Schedule: two bays at a time

What the job involves

1. The owner and the installer mark lift posts, floor drains and bay boundaries and confirm the lift maker's slab requirements.
2. A diamond grinder with dust collection grinds two bays; oil-saturated areas get a degreaser and an extra pass.
3. Cracks near the lifts are cut, filled and ground flush.
4. Moisture is tested in each bay; the bays that read high get a vapor-barrier primer.
5. The pigmented epoxy base with grit is rolled out and the top coat follows.
6. The first two bays cure per the data sheet while the second pair is done; bay lines are striped last.

Materials and prep

• Diamond grinder and industrial dust collector
• Degreaser, crack and spall repair mortar and joint filler
• Vapor-barrier primer, pigmented epoxy, grit and top coat
• Line paint, masking and moisture test kits

Add-ons often paired with this job

• Line striping and safety markings — +$300–$900. Bay lines and walkway marks are painted last and priced as a flat line.
• Saw-cut joint filling, about 150 linear feet — +$400–$1,200. Sawn joints are cleaned out and filled before the coating.
• Coved base, about 100 linear feet — +$1,500–$2,500. A coved edge along the parts-room wall is possible but not typical in a bay.

Why it is done this way

Of the three business examples this one has the thickest stack of slab surcharges. Oil and moisture add their own line, and cracks add another, so the per-square-foot rate is well above the base solid color rate. Both lines apply across the whole floor area, because the installer does not price a stained bay differently from a clean one.

The fluids are the other half of the conversation. The shop uses brake cleaner, a parts-washer solvent and a degreaser. For chemical resistance the right step is to check the product's chemical-resistance chart for the specific chemicals, concentrations and exposure times, not to assume a general rating.

Tires come off the road warm, and a warm tire lifting the coating is mostly a prep and product problem; grinding and the right system lower the risk. In a bay, a puddle of coolant or oil turns any coated floor slick, so the grit level is a trade between footing for the mechanics and how easily a rolling jack and a shop broom move across it.

Lifts are anchored by their makers into the slab, and the coating goes around the base plates according to the lift maker's instructions. The sensible order is to confirm the slab requirements with the lift maker before any grinding starts.

What would change the price

• The moisture readings are normal and the vapor-barrier primer is dropped.
• A lift post sits on a cracked or thin patch and needs more repair.
• A wash bay with hot water is added in urethane cement.
• The shop closes for a long weekend and does all four bays at once.
• The shop is a six-bay building of about 3,600 square feet.