What are the disadvantages of epoxy flooring? An honest list

The main disadvantages of epoxy flooring are the work and the waiting: the concrete has to be properly prepped, the job needs the right temperature and humidity, and the floor needs days before you can drive on it. Epoxy can also amber in direct sun, it will not stop a slab from cracking, and it can be slick when wet or oily. None of that is a deal breaker for most garages, but you should know it going in.

We sell quartz epoxy kits, so we would rather you hear the tradeoffs from us than find them out halfway through a pour. This is not a list of install mistakes (we covered those in what can go wrong with epoxy flooring). It is an honest look at the downsides of the material and the job itself.

1. Prep is real work

Epoxy is only as good as the concrete under it. Our installation guide states that about 95% of epoxy failures trace back to inadequate surface prep. Good prep means:

• Sweeping, vacuuming and scrubbing with a concrete cleaner or degreaser, especially oil spots
• Filling cracks and pits with concrete patch compound or epoxy crack filler (never silicone)
• Grinding the whole floor to a texture like 60 grit sandpaper with an angle grinder and diamond cup wheel or a rented floor grinder
• Vacuuming every bit of dust

Plan on about 2 to 6 hours or more of prep. A 500 sq ft garage with staining can take a full day. It is dusty, loud work. If you want to compare prep methods, read grinding vs acid etching for garage floor prep.

2. Your garage is out of service for days

A typical job is a weekend: prep and prime on day one, pour on day two. Then the floor needs time:

• Light foot traffic after 24 hours
• Full cure at 72 hours
• Heavy traffic and driving after about 5 days
• Water exposure after 7 days

That means finding somewhere else to park for most of a week. Details are in how long epoxy takes to cure.

3. Weather limits when you can do it

Epoxy can only be applied between 41°F and 90°F, with an ideal cure between 68°F and 77°F. Relative humidity must be below 65%. Below 55°F, cure time can double or more. Above 75°F, working time gets shorter, and above 85°F you should mix smaller batches.

In the Phoenix area that rules out midday pours for a big part of the year. Start early in the morning when it is cooler, which also helps with bubbles.

4. Short working time and no do overs

Once mixing starts, you have about 20 to 30 minutes of pot life. You mix one kit at a time with a drill and paddle, pour, spread with a squeegee, broadcast the quartz evenly and go over it with a spiked defoaming roller before it starts to set. There is no pausing to read instructions. Have your 22 inch squeegee with pole and 20 inch defoaming roller ready before you open anything.

5. You need safety gear and ventilation

Epoxy is a two part chemical system. Wear nitrile gloves, eye protection and a respirator, ventilate during application and the 72 hour cure, and keep children and pets away during that cure. You can find the SDS sheets on our safety data sheets page.

6. It can amber in direct sunlight

Bisphenol A epoxy can amber over time in direct sunlight. Our indoor kit does not have strong UV protection, so it is not for patios, driveways, pool decks or floors that sit in direct sun. For outdoor jobs we sell the Outdoor Washed Stone Quartz Epoxy Floor Kit, which lets water pass through. It is not a waterproofing membrane, so over a basement or living space you still need a separate waterproofing layer.

7. It will not fix a moving slab

An epoxy coating does not stop concrete from moving. If soil movement or settling cracks the slab later, the crack can show through. Fill existing cracks before coating, and read does epoxy stop garage floor cracks if your slab has a history.

8. Any smooth coating can be slick when wet

Water, oil or dust on any coated floor reduces traction. The quartz aggregate in our system adds texture and grip, and factory testing lists a slip coefficient of 0.4 or higher. Real slip resistance still depends on how evenly the aggregate is spread and what is on the floor. More in are epoxy floors slippery when wet.

9. It needs basic upkeep

Grit scratches epoxy over time. You will need to sweep or dust mop regularly, mop with a pH neutral cleaner, wipe spills fast and avoid vinegar, citrus, bleach and harsh solvents. See how to clean an epoxy garage floor for the routine.

10. Upfront cost compared to bare concrete

Bare concrete costs nothing. A 2 car garage is about 400 sq ft, which is 4 kits. Four indoor kits run $996 in Marble Grey or Desert Grey, or $1,200 in Black. Add about $95 for the squeegee, roller and pole if you do not own them, plus primer if your floor needs it (primer is sold separately). Compare that to national pro install pricing often quoted around $4 to $10 per square foot, or roughly $1,600 to $4,000 for the same garage.

Who should think twice

• Anyone who cannot give up the garage for about 5 days
• Slabs with ongoing moisture problems that have not been tested and dealt with
• Outdoor or sun exposed areas, if you were planning to use an indoor kit
• Anyone who wants to skip grinding and just roll something on

How to keep the downsides small

1. Moisture test the concrete and do the water droplet test before you buy.
2. Measure length x width, divide by 100 and round up. One kit covers 100 sq ft at about one eighth inch. Never stretch it; a thin coat will not level.
3. Pick a weekend with temperatures in range and start early.
4. Follow the installation guide step by step.
5. Call us before you start if anything about your slab worries you.

Our city planning guides help you plan for your local climate and garage size.

Quick answers

What is the biggest disadvantage of epoxy flooring?

The prep. About 95% of epoxy failures trace back to inadequate surface prep, so you need to clean, fill cracks, grind and vacuum the floor before you pour.

How long is the garage out of use?

Plan on a weekend for the work, then light foot traffic at 24 hours, full cure at 72 hours, driving after about 5 days and water exposure after 7 days.

Does epoxy turn yellow?

Bisphenol A epoxy can amber over time in direct sunlight. Keep the indoor kit indoors and use the outdoor washed stone kit for outdoor areas.

Will epoxy stop my garage floor from cracking?

No. An epoxy coating does not stop a slab from moving. Fill existing cracks before coating, but new cracks from settling can still appear.