If you are pricing up a resin floor, two words keep coming up: epoxy and polyaspartic. Both are a world apart from the tin of garage paint that peels within a year, and both are laid over your existing concrete. But they are different materials with different strengths, and the right one depends on how the floor will be used, how much sunlight it sees, and how long you can have the space out of action. Here is the honest breakdown, starting with the comparison most people are really after.
The quick comparison (scan this first)
| Epoxy | Polyaspartic | |
|---|---|---|
| Full cure | Around 7 days for vehicles | Same day to 24 hours |
| Lay in the cold? | Needs reasonable warmth | Yes, wide temperature range |
| Sunlight | Can yellow over time | UV-stable, holds colour |
| Hardness | Very hard, slightly brittle | Tough, slightly flexible |
| Scratch resistance | Good | Very good |
| Chemical resistance | Excellent | Very good |
| Deep metallic / heavy flake | Ideal | Usually a topcoat over it |
| Cost per m² | Generally lower | Generally higher |
| Downtime | A working week | Often a single day |
That table covers the decision for most people. The rest of this guide explains the why behind each row, so you are not surprised six months after the floor goes down.
What epoxy resin actually is
Epoxy is a two-part (two-pack) thermosetting resin: a resin and a hardener mixed on site, which triggers a chemical reaction that cures the liquid into a hard, solid plastic. The systems we lay are 100% solids, meaning there are no solvents to flash off as it cures. What you pour is what you get: a thick, dense film chemically bonded to the slab.
Because it is poured thick and self-levels, epoxy is the material of choice when you want depth and a flawless surface. It is what gives a metallic floor its three-dimensional, marbled look, and it carries a heavy flake broadcast well. The trade-off is time and temperature: a full chemical cure takes around seven days, and epoxy needs reasonable warmth to cure properly, which can be a real constraint in an unheated garage in January.
What polyaspartic actually is
Polyaspartic is a type of aliphatic polyurea, originally developed as a fast-curing protective coating for steel structures like bridges. That heritage tells you most of what you need to know: it cures very fast, it is tough, and it shrugs off sunlight. In flooring it is usually applied in thinner coats than epoxy, very often as the clear topcoat over a flake or colour base rather than as the whole build.
Its headline trick is speed. A polyaspartic system can be walked on within hours and back in full use the same day or the next, which is why it is the basis of our fast-cure floors. It also cures across a far wider temperature range, so it can go down in conditions where epoxy would simply sit there uncured.
Cure time and downtime: the biggest difference
This is the one that decides most jobs. Epoxy needs roughly 24 hours before light foot traffic and about seven days before you park a car or move heavy kit back. Polyaspartic re-coats in an hour or two and is typically ready for normal use within a day. If you run a unit and cannot lose a week of trading, or you only have a weekend to get the garage back, that alone can settle it.
There is a catch on the polyaspartic side, and it is the reason it costs more to lay. Once mixed, it has a short working time, often just minutes. It goes off fast and unforgivingly, so it demands an experienced installer moving at pace and cannot be left half-finished. Epoxy gives a longer, calmer working window, which is part of why hand-worked metallic effects are almost always done in epoxy: you need time to work the pour before it sets.
Sunlight and yellowing
Standard epoxy ambers under ultraviolet light. In a dark garage you will never notice, but in a unit with big south-facing doors, a glazed showroom, a conservatory floor, or anything outdoors, an exposed epoxy floor can yellow over the years, most visibly under a pale or white colour. Polyaspartic is UV-stable and holds its colour.
Why this matters for your build
Toughness: abrasion, impact and flexibility
Cured epoxy is very hard, which makes it excellent against abrasion but, being rigid, marginally more brittle under a sharp, concentrated impact. Polyaspartic is tough and slightly more flexible, so it resists scratching and sudden knocks well and copes better with a slab that expands and contracts with temperature.
In the real world, both perform on a busy workshop or an industrial floor. What separates a floor that lasts from one that does not is far more about the build thickness and the preparation than which of the two resins is on the label.
Chemical resistance
Epoxy has outstanding chemical resistance and remains the long-standing choice where oils, brake fluid, solvents and harsh cleaning chemicals are a daily fact of life. Polyaspartic is also highly resistant, and unlike epoxy it will not yellow from UV exposure at the same time, but for the most aggressive chemical environments a thick epoxy build is still very hard to beat.
Build thickness, finish and cost
Epoxy is poured thicker and is generally more cost-effective per square metre on a straightforward floor. It is also unbeatable for deep metallic pours and heavy flake. Polyaspartic goes on thinner, costs more per litre, and the fast working time adds to the labour, but it buys you speed and UV stability. On a domestic garage finished in flake, the difference in the finished look can be minimal; the difference in downtime is not.
Not sure which build suits your floor?
Tell us about the space and how soon you need it back. We will spec the right system and put it in an itemised written quote.
The hybrid reality: most good floors use both
It is worth knowing that the "one-day garage floor" you may have seen advertised is rarely pure polyaspartic. It is commonly a fast base coat, a flake broadcast, and a polyaspartic topcoat. The two materials are not really rivals, they are tools, and a well-designed floor often pairs them: epoxy for body and bond, polyaspartic for speed and colour protection on top. The job of the design visit is to spec the right build for your slab, your use and your timescale, not to push a single product.
So which should you choose?
Lean towards epoxy, or an epoxy-led build, when:
- You want a deep metallic or heavy flake finish.
- The floor is indoors and out of strong, direct sunlight.
- Cost per square metre is the priority and you can spare a week of cure time.
- The environment is chemically aggressive.
Lean towards polyaspartic, or a polyaspartic topcoat, when:
- You cannot have the space out of action for more than a day or two.
- The floor sees strong sunlight, or it is outdoors.
- You are laying in cold conditions where epoxy would struggle to cure.
- Scratch resistance and a little flexibility matter for how the floor is used.
The part that actually decides how long it lasts
Here is the thing neither manufacturer puts on the tin: the resin is not what makes or breaks the floor. Preparation is. A floor poured onto a dusty, unground or contaminated slab has nothing to bond to, and it will lift within a year whether it is the finest epoxy or the fastest polyaspartic.
The non-negotiable
About this guide
Who wrote this
This guide is written by the Obsidian Resin team: we prep and pour resin floors for garages, workshops, showrooms and commercial units across Leicestershire and the East Midlands. We lay both epoxy and polyaspartic systems, so the comparisons here reflect what we see hold up on real floors, not a preference for one product line.
Why we wrote it
"Epoxy or polyaspartic" is the question we are asked most at the design visit, and most of what is written about it online is either a sales page for one product or a spec sheet that never answers the practical question. This is the explanation we would give you in your garage.
Our honest position
We have a commercial interest in you choosing a professionally laid floor, and we are upfront about that. We do not push one resin over the other; we spec what suits the job. Often that is epoxy, often it is a hybrid, and where downtime or sunlight rules, it is polyaspartic. The guide is meant to be useful whether you use us or not.
Frequently asked questions
- Is polyaspartic better than epoxy?
- Not better, different. It cures faster and resists UV, but epoxy is often more cost-effective and better for deep metallic and heavy flake. The right answer depends on the job.
- Can you really use the floor the same day with polyaspartic?
- For most domestic floors, yes: walk-on in hours, light use the same day, parking the next. Larger or colder jobs take a little longer.
- Will an epoxy garage floor go yellow?
- Only where it sees strong UV. A dark, indoor garage will not noticeably yellow. A sunlit or glazed space might, which is when we use a polyaspartic topcoat or build.
- Which lasts longer?
- Both last many years when laid properly. Lifespan is decided far more by preparation and build thickness than by which resin is used.
- Can I put polyaspartic over an existing epoxy floor?
- Often, if the existing floor is sound and properly abraded first. We assess it at the design visit and tell you straight if it needs more than a topcoat.
- Which do you recommend for a home garage?
- Usually a flake build with a hard topcoat. Whether the base is epoxy or fast-cure comes down to your timescale and the conditions on the day, which we work out at the visit.