Few decisions affect a working facility as directly as its floor. It takes every forklift wheel, every drum of acid, every steam wash-down and every monsoon-season spill, day after day. Specify the wrong system and you are looking at premature failure, recurring shutdowns and repair bills that dwarf the original cost. Specify the right one and the floor quietly does its job for years. The two workhorses of industrial flooring are epoxy and polyurethane (PU), with PMMA (methyl methacrylate) filling a third niche where speed is everything. They look similar once cured, but they behave very differently under heat, chemicals and impact. This guide explains how each resin system performs, where it belongs and how to match the build-up to your operation — written for Indian architects, project engineers, contractors and facility owners who have to live with the result.

A self-levelling (self-smoothing) epoxy is the floor most people picture when they think ‘epoxy’ — a seamless, mirror-finish surface typically laid at 2 to 3 mm over a primed and repaired substrate. It is ideal where you want a clean, dust-free, chemically resistant floor without heavy thermal or impact demands: pharmaceutical clean-room support areas, electronics and assembly, packaging halls, showrooms, laboratories and general manufacturing. Thinner epoxy systems also exist — roller-applied coatings at a few hundred microns for light-traffic areas, and broadcast or screed systems where slip resistance or extra build is needed. The catch is heat and movement. Standard epoxy softens and can discolour under sustained high temperature, and being rigid it does not tolerate thermal cycling well. Pour boiling water or run a steam hose over an epoxy floor day after day and it will eventually craze, blister or debond. That single limitation is what pushes many process facilities toward PU.

• Best for: clean, dry-to-moderately-wet areas with foot and light-to-medium wheeled traffic
• Typical build: 2–3 mm self-levelling; thinner coatings for light duty, screeds for heavy duty
• Watch-outs: limited thermal tolerance, rigid (poor with thermal shock), can yellow under UV unless a PU/aliphatic topcoat is added

On chemical resistance, both perform well, but they trade strengths. Epoxy handles a wide range of acids, alkalis, solvents and oils and is excellent for secondary containment and chemical storage, where rigidity and a fully sealed surface are assets. PU-cement edges ahead against organic acids — lactic, citric, acetic — and against the fats, sugars and aggressive cleaning agents found in food and dairy plants, where epoxy can be attacked over time. On thermal resistance there is no contest: standard epoxy is comfortable up to moderate warmth but struggles with sustained heat and fails under thermal shock, whereas PU-cement screeds can withstand steam cleaning and hot-liquid spillage and tolerate rapid hot-cold cycling. On abrasion and impact, both are strong; epoxy is very hard and abrasion resistant, while PU is tougher and more impact- and gouge-resistant because it flexes rather than fractures. The honest summary: choose epoxy for clean, dry, chemical-storage and general areas; choose PU wherever heat, thermal shock, food chemistry or heavy impact is in play. For containment bunds and corrosive-process areas, pair either system with the right protective coatings on walls and steelwork for a complete barrier.

• Chemical: epoxy strong on mineral acids, solvents, containment; PU stronger on organic acids, fats, sugars, food chemistry
• Thermal: PU-cement clearly superior — handles steam wash-down and thermal shock that crack epoxy
• Abrasion/impact: epoxy very hard; PU tougher and more impact-resistant due to flexibility

Thickness is a specification decision, not an afterthought — it should follow from the traffic, the chemical and thermal exposure and the condition of the substrate. As a working framework: thin-film coatings at roughly 0.1–0.5 mm (roller or sealer-grade epoxy/PU) suit light foot traffic, dust-proofing and aesthetics; self-levelling systems at 2–3 mm give a seamless, durable surface for medium-duty industrial and commercial floors; broadcast or mortar systems at 3–6 mm add slip resistance and impact capacity through aggregate; and heavy-duty screeds at 6–9 mm (and occasionally more) — almost always PU-cement in process plants — take the worst combination of impact, abrasion, heat and chemical attack. Thicker is not automatically better: an over-thick rigid epoxy can be more prone to stress cracking, while a flexible PU screed at the right build outperforms it. Whatever the system, the substrate must be sound — laitance removed, surface mechanically prepared, moisture under control, and any defects made good with the appropriate concrete repair mortars before priming. The bond is only ever as good as the concrete beneath it.

• 0.1–0.5 mm: thin-film coatings — light traffic, dust-proofing, aesthetics
• 2–3 mm: self-levelling — seamless medium-duty industrial/commercial floors
• 3–6 mm: broadcast/mortar — slip resistance and added impact capacity
• 6–9 mm+: heavy-duty PU-cement screeds — maximum impact, abrasion, heat and chemical resistance

Work through five questions in order and the right system usually selects itself. 1. Temperature and thermal shock — any steam cleaning, hot spillage or hot-cold cycling? If yes, specify PU-cement; epoxy will fail. 2. Chemicals — what is actually spilled, and how often? Organic acids, fats and sugars favour PU; mineral acids, solvents and containment favour epoxy. 3. Loads and impact — foot traffic, pallet trucks, forklifts or steel-wheeled loads? Heavier impact pushes toward thicker builds and PU. 4. Hygiene — food, beverage or pharma? PU-cement with coving and falls to drains. 5. Downtime — how long can the area be closed? If almost none, consider PMMA; otherwise epoxy or PU on a normal programme. Then size the thickness to the duty and confirm the substrate is sound and dry before anything is laid. Because the answer is rarely one product but a build-up — primer, body coat, topcoat, coving and joint detailing — it pays to involve an experienced applicator early. Space Arc supplies and applies epoxy, PU and PMMA systems from the leading manufacturers across India; our team can survey the substrate, recommend the system and stand behind the installation.

• Ask in order: thermal shock, chemicals, loads/impact, hygiene, downtime
• Specify the full build-up — primer, body, topcoat, coving, joints — not just a single product
• Confirm a sound, dry, prepared substrate before laying — it governs the result more than the resin
• Involve the applicator early; Space Arc surveys, specifies and installs pan-India
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