Coating and Concrete Glossary

The point at which mixed coating stops flowing and sets as one mass. It is a moment rather than a window, it is measured in a laboratory rather than on your floor, and your usable time ran out well before it arrives.

A phenolic epoxy resin carrying far more reactive sites than standard bisphenol A epoxy, which cures into a much denser network. That density is the whole product: it is what resists acids and solvents, and it is the reason novolac is the right call on a small number of floors and money thrown away on the rest.

The point at which a coating stops being sticky to the touch. It is the first and weakest of the cure stages a data sheet lists, it says nothing about strength, and it is the milestone most often mistaken for a floor being finished.

A material whose thickness changes with how hard it is being worked: thin while it is stirred, brushed or troweled, and thick again within moments of being left alone. It is the property that lets a coating stay on a vertical surface instead of running down it.

The lowest temperature at which a liquid gives off enough vapor to ignite in air, if something is there to ignite it. It is a property of what is evaporating rather than of the liquid itself, which is why it matters far more for some coating products than others.

Volatile organic compounds: the part of a coating that leaves as vapor instead of staying on the floor, quoted as a weight per unit volume. It governs where a product may legally be used and whether a building can stay occupied, and it is routinely misread as a safety rating.

A measure of how far a standard point sinks into a cured material under a standard force, read off a durometer and reported on a Shore scale. It describes resistance to being pressed into, which is one property of a floor rather than a summary of its quality.

A deliberate pause between mixing a product and applying it, called for by some data sheets so the reaction can get properly underway before the material goes down. Also called sweat-in time, and it is subtracted from your working window rather than added to it.

The reaction in which molecules bond not only end to end but across to each other, turning two poured liquids into a single connected solid. Almost every property a coating is sold on is a consequence of how completely this happens.

The heat a curing reaction releases as it runs. Every epoxy makes it, and what decides whether it matters is not how much material you mixed but how easily that heat can leave, which is a question about shape rather than quantity.

The sheeting laid under a concrete slab before it is poured, to slow ground moisture entering the slab from below. It shares most of a name with the barrier you roll onto a finished floor, and the two are so often confused that a permanent condition gets treated as a specification question.

Rolling back over coating that has already been spread, to even the film and work it into the surface rather than to put it down. It is a distribution step, not a finishing one, and most of the trouble it causes comes from continuing it after it has done its job.

A break in a coating film: somewhere the material never arrived, or arrived so thin that the concrete underneath is effectively bare. The floor around it can be perfect, which is exactly what makes it worth a name.

One thousandth of an inch. It is the unit almost every coating specification, data sheet and film gauge is written in, and it is not related to the millimeter despite the resemblance.