An acid resistant floor coating protects concrete where ordinary floors fail within months. Concrete is alkaline, so acids dissolve its cement paste and loosen the aggregate. In Egypt we see this damage in chemical plants, battery charging rooms, laboratories, fertiliser stores and plating shops. This guide explains how to match the coating to the acid, which systems the data sheets support, and how to detail drains and edges.
Contents
- How Acids Attack Concrete Floors
- Matching an Acid Resistant Floor Coating to the Chemical List
- Choosing an Acid Resistant Floor Coating System
- Preparing Concrete for an Acid Resistant Floor Coating
- Detailing Drains, Coves and Joints
- Applying an Acid Resistant Floor Coating Step by Step
- Common Mistakes
- FAQ
- Conclusion
How Acids Attack Concrete Floors
Acid spills react with the calcium compounds in hardened cement. As a result, the surface first loses its skin, then the sand, and then whole pieces of aggregate. Repeated spills also soak into cracks and joints, where they reach the steel.
The damage depends on three things:
- acid type, since sulphuric, hydrochloric and organic acids behave differently;
- concentration, because a dilute rinse is far milder than a concentrated spill;
- contact time and temperature, since a hot spill left for hours does the most harm.
So the first question is never “which product?”. Instead, it is “which chemicals, how strong, how hot and for how long?”.
Matching an Acid Resistant Floor Coating to the Chemical List
Every acid resistant floor coating starts with paper, not resin. In other words, each chemical area needs a written list of the substances that can reach the floor. The supplier’s resistance data must then cover each one. The table shows what the data sheets state.
| Product | Acids named in the data sheet | Other data |
|---|---|---|
| Sikafloor-92 EG (Sika Egypt) | Sulphuric, hydrochloric and acetic acid up to 30% | Sodium hydroxide up to 40 g/L, chlorides up to 20 g/L |
| Sikafloor-92 SL (Sika) | Hydrochloric and sulphuric acid 50% (slight colour change); acetic acid up to 30% (no effect) | Sodium hydroxide 50% (no effect) |
| Kemcrete SL (Prokem) | Acids, alkalis and solvents, no concentrations given | Heat resistance from −40 to +120 °C |
Notice the gaps. The Sikafloor-92 EG sheet also says “please ask for a detailed chemical resistance table” for anything else. Likewise, the Kemcrete SL sheet names no acids or strengths. Therefore, for any chemical outside these lists, we ask the maker for written confirmation before choosing.
Test reports for such materials usually follow ASTM C267, which measures weight, appearance and strength after immersion. It is a useful guide, but it is not a promise of field life. Real spills come with heat, abrasion and cleaning as well.
Choosing an Acid Resistant Floor Coating System
Coating for moderate exposure
Sikafloor-92 EG is a two-component, solvent-free epoxy coating, and its data sheet comes from Sika Egypt. Its sheet lists the chemical and pharmaceutical industry, food processing and water industry among its uses. It also gives a compressive strength of about 55 N/mm² and an abrasion loss of 55 mg.
- Primer: one coat of Sikafloor-161 or Sikafloor-94, about 0.2–0.3 kg/m².
- Coating: two coats of Sikafloor-92 EG, about 0.25–0.35 kg/m² each.
- Mixing ratio: A : B = 4 : 1; pot life 45 minutes at 20 °C.
This build suits labs, washdown areas and stores with occasional splashes of acids within its listed limits.
Self-levelling topping for heavier exposure
Where spills are frequent or traffic is heavier, a thicker layer resists longer. Sikafloor-92 SL is a self-smoothing epoxy topping of 1 to 4 mm. Its sheet lists chemical industry facilities and laboratories, and reports 50 N/mm² compressive strength to ASTM C579.
Kemcrete SL from Prokem is an Egyptian self-levelling epoxy mortar. Its sheet lists chemical factories, hospitals and laboratories, food and pharmaceutical plants and cold stores. It gives a compressive strength of 60–70 N/mm², zero water absorption and a consumption of 4–8 kg/m² for 2–4 mm. Its stated heat range also helps where hot liquids reach the floor.
The primer underneath
Sikafloor-161 is the epoxy primer named in both Sika systems. Its sheet asks for one layer of 0.15–0.2 kg/m² on low-porosity concrete, and two layers on medium-porosity concrete. It must not go on substrates with rising moisture. In addition, its permanent dry-heat limit is +50 °C, so hot processes need the topping to carry the load.
When an epoxy acid resistant floor coating is not enough
Some cases go beyond what these sheets state. For example, acids stronger than the listed concentrations, strong oxidising acids or constant hot spills. In those cases we never guess. Instead, we ask the maker for its full resistance table or a specialist system it confirms in writing.
Preparing Concrete for an Acid Resistant Floor Coating
An acid resistant floor coating is only as good as its bond. The sheets set clear rules:
- Remove laitance, oil and old coatings by grinding or light blasting.
- Cut out acid-damaged concrete back to sound material.
- Fill cracks and holes with epoxy mortar, for example Sikafloor-161 with sand.
- Check moisture: below 4% for the 92 EG and 92 SL sheets and for Kemcrete SL.
- Check that the concrete is at least 3 weeks old.
- Keep the surface 3 °C above the dew point, and humidity within the sheet limit.
- Vacuum all dust before priming.
On old acid-soaked floors, Target crews also wash and neutralise the surface first. Residual acid in the pores can spoil adhesion.
Detailing Drains, Coves and Joints
Even the best acid resistant floor coating fails at weak details. In fact, most failures in chemical areas start at the edges, not in the middle of the floor. Our crews pay special attention to:
- coves where the floor meets walls and plinths, so spills cannot reach the wall base;
- falls towards drains, so acid does not stand on the surface;
- drain and gully edges, where the coating must lap into the drain body;
- joints, which need a chemical-resistant joint filler suitable for the same chemicals;
- bunds around tanks, coated on the floor, walls and top as one system.
Applying an Acid Resistant Floor Coating Step by Step
Target installs chemical-resistant floors across Egypt. On a typical job, the sequence looks like this:
- Agree the chemical list and concentrations with the client in writing.
- Prepare and repair the concrete, then test moisture.
- Apply the Sikafloor-161 primer at the right rate for the porosity.
- Form coves and fill details with epoxy mortar.
- Apply the coating or self-levelling layer within its pot life.
- Roll self-levelling layers with a spiked roller to release air.
- Protect the floor from water, chemicals and traffic until cured.
Cure times matter here. Sikafloor-92 EG and 92 SL take foot traffic after 24 hours, light loads after 3 days and full cure after 7 days. Similarly, Kemcrete SL must stay free of water, liquids and traffic for at least 24 hours and reaches final hardness after 7 days. So chemicals should not touch the floor before full cure.
Common Mistakes
- Choosing a product by name without checking the actual acid and strength.
- Coating over concrete that is still contaminated with acid.
- Leaving joints and drain edges uncoated.
- Allowing spills on the floor before the 7-day cure.
- Ignoring heat: a hot acid is harsher than the same acid cold.
FAQ
Is every epoxy floor an acid resistant floor coating?
No. Resistance varies widely between products. That is why we compare the data sheet limits with your chemical list first.
What about battery charging rooms?
Battery rooms involve sulphuric acid. Check the concentration your battery supplier states against the product’s sheet limit, then design the system and coves around it. Our epoxy flooring works team can survey the room.
Can an acid resistant floor coating suit a food plant?
Some of these products list food plants too. However, food areas bring their own hygiene and cleaning needs, covered in our food factory floor coating guide.
Conclusion
An acid resistant floor coating works when the chemical list drives the choice, not the brand alone. A primed epoxy coating suits moderate splashes, while thicker self-levelling epoxy mortars suit heavier exposure. Careful coves, drains and joints then keep the acid off the concrete.
For more on our coating options, see epoxy coating systems. Contact Target with your chemical list to design the right floor.
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