How to measure a floor for an epoxy estimate

Measuring a floor for an epoxy estimate takes more than length times width. You need the square footage of every area to be coated, the linear feet of everything priced by the foot (cracks, joints, stem walls, cove), a count of steps, and a record of the slab’s condition, the access and the power. Get all of that on the first visit and the estimate almost writes itself. Miss it, and the gap comes out of your margin on install day.

This is the measuring and inspection part of the site visit. The epoxy flooring sales process covers the rest of the visit, and how to price epoxy flooring turns the numbers into a price.

Tools for the site visit

• A laser distance measure and a 25-foot tape; a measuring wheel for large commercial floors.
• Graph paper or a measuring app for the sketch.
• A phone camera, a flashlight and chalk or a marker.
• A spray bottle of water, for the sealer check.
• A Mohs scratch kit, or at least a pocketknife, to judge slab hardness.
• A moisture meter or test kit, or the materials to start a test.
• A copy of the estimate template, so you collect everything it asks for.

Measure the floor

Measure wall to wall at floor level, and measure each separate area on its own: each bay, the bump-out, the landing by the house door. Write feet and inches, then convert inches to decimal feet by dividing by 12, so 6 inches is 0.5 ft and 9 inches is 0.75 ft. Most laser measures will show decimal feet directly.

At the garage door, measure to where the coating will stop, usually the outside edge of the slab under the door, and note where the driveway apron starts if the customer wants that coated too.

Odd shapes are just simple shapes added together:

Draw a sketch and write every dimension on it. Mark the door, drains, cracks, joints and anything you’ll photograph. The sketch goes in the job file with the estimate, and it’s what the crew reads on install day.

What to deduct and what to leave in

Deduct only what stays put and won’t be coated: built-in cabinets, fixed workbenches, raised platforms and equipment pads. Leave in posts, pipes, small drains and the spot under a water heater. They don’t save you any material worth counting, and cutting around them takes extra time.

Movable things aren’t deductions either. Shelving, freezers, toolboxes and the customer’s car all have to come out, and the estimate should say who moves them.

Price the area you measured. Waste belongs in the material math (rough, thirsty concrete drinks more primer, and some flake is always lost), not in the square footage you show the customer. The coverage calculator and the flake calculator both have a waste setting for that. On small floors, check the result against your minimum job price.

What to record about the slab

The base price assumes a sound, dry, clean slab. Everything else gets recorded, because it changes the system, the schedule or the price:

Four quick checks fill in most of that table:

• Water drops. Spray a little water on the bare slab. If it soaks in and darkens the concrete within a minute or so, the surface is open. If it beads or just sits, there’s a sealer, densifier or coating that has to come off. Removing old floor coatings covers how to identify what’s there.
• Cracks and joints. Run a fingernail or coin across each crack to feel for offset, and measure the widest point. Crack and joint repair before coating explains which ones you can fix and which ones you write out of the warranty.
• Moisture. Look for efflorescence, dark patches and rust or water lines low on the walls, then test or schedule the test. A calcium chloride test sits for about three days, so plan the return visit now. The methods are in concrete moisture testing.
• Hardness. A Mohs scratch kit tells you which diamonds to bring and how fast the floor will grind; see diamond tooling for concrete grinding.

Access, power and the space

These don’t change the square footage, but they decide whether the install goes to plan:

• Access. Door widths, steps, gates and the distance from the trailer to the floor. A basement or a second floor may need a smaller grinder or extra hands to carry it.
• Power. Find the panel and the outlets you’d use. A 10-inch single-disc grinder runs on a dedicated 115-volt circuit; most dual-disc and planetary grinders need 230 volts, and the dust extractor needs its own circuit. With no 240-volt outlet (a dryer, range or welder outlet), plan on a generator. Concrete grinders for epoxy prep lists what each machine needs.
• Ventilation. Doors and windows that open, and whether the space shares air with the house or an occupied business.
• Contents. What’s in the space, who moves it, where it goes and where the cars park until the floor is cured.
• Restrictions. HOA rules, noise hours, business hours on commercial jobs, and kids and pets in the house.
• Staging. Where the trailer parks and where you can mix.

Photos to take

• The whole floor from each corner and from the doorway.
• Every crack, spall and stain with a tape measure in the shot for scale.
• The edges of any old coating, and any peeling.
• Moisture signs: white deposits, dark patches, water lines on the walls.
• Stem walls, steps, thresholds and drains.
• The electrical panel and the outlets you plan to use.
• The access route, including anything already damaged along it: walls, door tracks, the driveway.

Number the photos on your sketch. They back up every adder on the estimate, and they’re your record of damage that was there before you arrived.

From measurements to a price

Here’s how one visit adds up, for a two-car garage with a workshop bump-out:

The 604 sq ft goes into the coverage and flake calculators for gallons, kits and boxes. The cracks, joints, stem walls and steps each go on their own line, priced per linear foot or per step, as in price the adders as separate lines. Then the job pricing calculator turns materials, crew days and visits into a price, and the estimate template puts it in front of the customer with the scope written out. Where the stem walls meet the floor, offer cove base as an option on the same estimate.

On install day, the job checklist picks up where the visit left off. If you want to see how a full installation runs before you start quoting them, The Epoxy Playbook pairs recorded hands-on installation training you can replay with the business side, including pricing, quoting and selling the job.