Epoxy flooring questions, answered for the coast

No, but the humidity decides when we can work. The epoxy data sheet we follow caps the air at 80% relative humidity during application. Durban's long-term average is 80% in January, February and March, and 77% over a whole year, so a summer reading can land right on the limit. We check a hygrometer on site before anything is mixed, and if the air is above 80% we wait for it to drop or move that coat to another day.

Dew point means the temperature where water vapour in the air starts turning into droplets. The bare slab and the uncured coating both have to stay 3 °C or more warmer than that point, or condensation and a blemish known as blooming can form on the finish. The same data sheet notes that cool temperatures and high humidity make blooming more likely. A shaded slab on a damp coastal morning can slip inside that margin without anyone noticing, so we measure slab temperature and dew point instead of going by how the day feels.

It does. Heat shortens the time a mixed batch stays workable: roughly 25 minutes in 20 °C air and closer to 15 minutes in 30 °C air for the epoxy we quote from, and the product is not applied when the air is above 30 °C. Durban's average daily high is 28 °C in January and 28.6 °C in February, which is close to that ceiling. On hot days we mix smaller batches so each one is spread well before it begins to set, and we keep coating out of the hottest part of the afternoon.

Temperature sets the pace. The manufacturer gives roughly 24 hours to foot traffic and 7 days to full cure at 20 °C, and roughly 18 hours and 5 days at 30 °C. Durban's monthly mean runs from about 17 °C in July to 25 °C in February, so a winter floor sits at the slower end. For a full 24 hours the new coat must stay dry, with no condensation or rain reaching it, which matters at a garage door that takes rain on a windy day.

With instruments, because a slab can feel dry and still fail. The data sheet allows a maximum of 4% moisture by weight and names three ways to measure it: a handheld moisture meter, a CM measurement or oven-drying a sample. It also rules out rising moisture, checked with the ASTM polyethylene-sheet test. Readings go on your quote so you can see what we found.

The epoxy does not go straight onto it. Above 4% moisture, the manufacturer's route is a temporary moisture barrier laid first, and the coating is not to be applied at all over rising moisture. If your floor needs a barrier, it appears as its own line on the quote. If we think the damp problem has to be fixed before any coating is worth doing, we tell you that instead.

The top of a slab carries a weak, dusty layer called laitance, along with whatever has soaked into it over the years. The data sheet calls for mechanical preparation to remove the laitance and open up the surface, then removal of all dust, preferably by brush or vacuum. It also expects sound concrete, rated at 25 N/mm² or more in compression, that holds on in a pull-off test to 1,5 N/mm² or more. Grinding is how we reach that on most floors, and it exposes soft patches before they are hidden under resin.

It can. The manufacturer warns that the colour can shift or vary where direct sunlight hits it, and says performance is not affected. Where a floor catches sun, such as a stoep, a patio or the strip inside an open garage door, we quote a UV-resistant topcoat over the epoxy to protect the colour.

Yes, with a textured surface. Quartz sand is scattered into a fresh coat until the surface is covered, left to set, vacuumed to lift the loose grains, and then sealed under a final coat that locks the rest in place. That leaves a grip you can feel underfoot. These spots usually get sun too, so the topcoat choice matters as much as the texture does.

Wipe up spills as soon as they happen. For regular cleaning the manufacturer lists rotary brushes, scrubber-dryers, high-pressure washers and wash-and-vacuum machines with suitable detergents, which suits a factory or warehouse. In a home, a soft broom and a damp mop with a mild cleaner do the same job on a smaller scale.

Our appointed installation contractor, working on our behalf. We handle the enquiry, the site visit, the recommendation and the written quote, and the contractor carries out the preparation and coating to that quote. If something about the work needs sorting out, you come to us.

Ask about it when you receive your quote. What applies depends on the system, the state of the slab and how the floor will be used, so we set it out in writing for your job instead of giving one figure for every floor.

Your suburb, a rough floor size and what the space is used for. Mention anything unusual: damp marks, flaking paint, tiles that would need lifting, or a step down from the house. When we reply we will ask for a few daylight photos, then come back with questions or a time to test the slab.

Not at the moment. For now we take enquiries by email and through the quote and contact forms, and we work through them Monday – Friday from 08:00 to 17:00 and on Saturday from 08:00 to 12:00. Leave a number in the form if you would rather we called you.