The first resin floor I specified failed in eleven months, and it failed for a reason that had nothing to do with the resin. The slab underneath had been power-trowelled to a glassy burnished finish, nobody ground it, and the coating let go in sheets the size of a dinner plate. That job taught me the thing that separates a decorative resin floor from a garage coating out of a bucket: almost all of the quality is decided before the first pour, in surface preparation and moisture testing, and almost none of it is decided by the product on the label.

The substrate is the specification

Mechanical preparation is not optional. Diamond grinding or shot blasting to an open, uniformly porous surface — the profile most manufacturers ask for sits around CSP 2 to CSP 3 for a thin-film build and coarser for a self-levelling system — is what gives the resin something to key into. Acid etching is a poor substitute and leaves residue behind. Moisture is the second gate: a relative humidity probe test to the ASTM F2170 method, with the probe set in a drilled hole and left to equilibrate, tells you what the slab is actually doing at depth, which a surface plastic-sheet test does not. Most resin systems want internal RH below 75 to 80 per cent, and a slab on grade with no vapour retarder under it may never get there without a dedicated moisture-tolerant primer.

Build-ups and what each one is for

A roller-applied two-coat epoxy at roughly 10 to 15 mils total is a coating, and it belongs in a utility room. A broadcast system — primer, flake or quartz aggregate broadcast to refusal, then one or two clear coats — lands around 1/8 in and gives you a floor with genuine impact resistance and a slip profile you can tune with the grade of aggregate. A self-levelling metallic or pigmented pour at 1/8 to 3/16 in is the one that reads as a finished architectural surface, and it is also the one that shows every defect in the substrate. On a desert slab with high summer surface temperatures, pot life shortens dramatically, which is why epoxy flooring installers in Las Vegas tend to schedule pours for early morning and keep material in conditioned storage until the moment it is mixed.

Aggregate, colour and the gloss decision

Colour in resin comes from three places: pigment in the resin itself, broadcast media sitting in it, and metallic pigment moved around by the installer during the pour. Pigment alone gives a flat, even field that behaves like paint and shows scratches as a lighter line. Broadcast quartz gives a speckled surface that hides wear better than any solid colour and is the sensible choice for a workshop, a mudroom or anywhere grit gets tracked in. Gloss level is a maintenance decision more than an aesthetic one: a full-gloss clear coat looks superb for eighteen months and then records every scuff, while a satin or matte topcoat at around 30 to 45 gloss units ages far more gracefully. Anti-slip additive belongs in the topcoat, not the body, so it can be renewed.

Detailing the edges

Edges are where resin floors look homemade. A coved skirting, formed in resin mortar to a 1 to 2 in radius up the wall, gives a seamless junction and is standard in kitchens and wet areas. Where the floor meets timber or tile, a saw-cut and a metal trim reads as a deliberate line; a feathered edge does not, and it chips. Moving joints in the slab must be carried through the resin, not bridged — a control joint filled with semi-rigid filler and then re-cut through the coating will crack cleanly along the joint instead of wandering across the field. Expect a full system in a domestic room to run through three to five days of work including cure time between coats, with cure to light foot traffic typically 24 hours and to full chemical resistance around seven days at 70°F.

What it costs and how long it lasts

Thin-film coatings run in the low single digits per square foot; a broadcast quartz or flake system with a coved edge generally lands between $8 and $14 per square foot in most metros, and a designed metallic pour runs higher, often $12 to $20, because it is a hand-worked finish with no second chances. Lifespan in a domestic setting is 10 to 20 years for the body of the floor, with the topcoat as a wearing layer that can be screened and recoated every five to eight years for a fraction of the original cost. A floor that is failing at the bond line cannot be rescued that way, which brings the argument back to preparation.

Frequently asked questions

Can a resin floor go over an existing tile floor? Sometimes, if the tiles are sound, fully bonded and mechanically abraded, but the joint lines usually telegraph through within a year. Removing the tile and preparing the slab is the more durable path.

Does a resin floor need underfloor heating to be turned off during installation? Yes, typically off for 48 hours before and brought back up slowly over several days after, because thermal movement during cure is one of the common causes of early cracking.

Will a pigmented resin floor fade in direct sunlight? Standard epoxy ambers noticeably under UV. Where a floor takes direct sun, a polyaspartic or polyurethane topcoat over the epoxy body keeps the colour stable.