Chemical Resistance

Brake fluid, gasoline, road salt, and what the topcoat is actually rated for.

The layer a spill actually touches is the clear topcoat, not the coating under the flake. That sounds obvious, and it is the thing most garage-floor pages get wrong: they describe the body coat’s chemistry and let you assume it is what your brake fluid meets. It is not. The topcoat here is Anvil Coat ClearTop, a clear polyaspartic made by Duromar, and the honest version of this page is about what that film does — including where our evidence for it is still second-hand.

What a garage floor actually meets

Brake fluid. Glycol-ether based, and the reason it gets named first is that it is aggressive towards paint and towards many coatings that shrug off oil without trouble. It is the spill that finds out what a floor is made of.
Motor oil, gear oil, transmission fluid. The routine case. The problem here is usually staining rather than attack — a porous or unsealed floor absorbs and darkens permanently.
Gasoline and diesel. Hydrocarbons, and the case this system is strongest against.
Road salt. Brine dripping off a car all winter, sitting in the same spots. Concrete hates it. The coating job is to stop it reaching the concrete.
Battery acid. Sulfuric acid. Rare, but when it happens it is a coating failure or it is nothing.

What the topcoat is rated for

These are the topcoat’s own published ratings, measured at 70°F by Duromar and taken from the data sheet for the clear coat itself rather than inferred from the layer beneath it. They match the body coat’s exactly, which is not a substitution — both are aspartic chemistry, and Duromar rates them the same:

Hydrocarbons — Good. Gasoline, diesel, motor oil. The most common thing a garage floor meets is the thing this film handles best, which is a fortunate way round.
Alkalis — Good. Covers the brine and de-icing salt case.
Inorganic and organic acids — Fair. Battery acid sits here. Fair is a real rating, not a euphemism: it means neutralize and rinse rather than wipe and forget.
Solvents — Fair. Brake fluid, carburetor cleaner, lacquer thinner. Wipe them up rather than leaving them to sit.
pH 3.0 to 12.0. The working range. Almost everything in a domestic garage falls inside it.

Why we publish “Fair” instead of hiding it

A coating rated Good on everything is a coating whose ratings mean nothing. This is a garage floor, not a chemical plant containment bund, and the categories above are honest about where the limits are. If you need a floor that holds concentrated acid indefinitely, that is a different product — an epoxy novolac — and it is a genuinely worse choice for a garage, because it cures too fast to install by hand and yellows in daylight.

Why the solids figure belongs in this conversation

Every layer in this build is 100% by weight solids. Nothing evaporates out as it cures, so there is no solvent leaving the film and no porosity where the solvent used to be. What goes down is what stays: a dense, continuous film with no path through it. A thin coating that dried by evaporation has a route for a spill to reach the concrete; a thick 100% solids film does not.

We publish the categories, not a reagent-by-reagent chart

Two limits on that, both worth saying. These are categories rather than a tested list of the specific fluids in your garage, and a reagent-by-reagent claim needs a chart no document on hand contains. They are also the manufacturer’s categories rather than ANVIL’s own testing, and we have not run a reagent panel on this build. Status: reagent-by-reagent resistance chart not yet supplied.

If a garage is not the whole story

Everything above describes the standard system, and for a car, a workbench and the occasional spill it is more than enough. There is a second body coat available for people whose floor sees worse.

Anvil Coat-EP Ultra is a non-yellowing high-performance lining, and its numbers are in a different class: a pH range of 1.5–14.0 against 3.0–12.0 for the standard topcoat, and Excellent on hydrocarbons — which in a garage means gasoline, diesel and oil. It is rated to 375°F in service.

That is a chemical-plant specification, not a marketing tier. If you are running a workshop that sees solvents, battery acid or aggressive cleaners, it is the one to ask about. For a domestic garage it is more floor than the job needs, and we would rather say so than sell it to you.

Resistance is not immunity

Chemical resistance is measured as a length of contact time, not as a yes or no. Every resistance rating in the industry assumes the spill gets cleaned up. Leave anything standing on any coating long enough and you are running the test rather than reading it.

Wipe spills up. That is the whole maintenance instruction, and it is worth more than any rating on this page.
Battery acid should be neutralized and rinsed, not wiped and left.
Resistance is a property of the fully cured film. The floor reaches full service at 5 days. Before that, the network is not finished and the floor is not the floor described here.
The base coat beneath the flake is a separate question. It carries good chemical resistance of its own, but it is not the layer meeting the spill and only becomes relevant if the clear coat has been worn or cut through.