Sika Sikafloor-291
A three-part, solvent-free epoxy self-smoothing screed that levels and reprofiles concrete at 1.5-3 mm, giving your final epoxy, PU or PMMA floor a flat, sound base to sit on.
What is it?
A three-component, solvent-free epoxy self-smoothing underlay and levelling screed from Sika, mixed on site from resin, hardener and a graded powder filler.
Where is it used?
Under industrial epoxy, polyurethane and PMMA coatings, and beneath tiles, sheet floors, carpet or timber where the slab first needs levelling.
Why use it?
It corrects undulations and worn patches in one economical pour, delivers roughly 60 N/mm2 compressive strength, and leaves a fine-textured surface ready to bond the finish coat.
How is it applied?
Prime with Sikafloor-290, mix A+B+C for the full time, spread with a trowel to 1.5-3 mm and de-aerate with a spiked roller while the edge stays wet.
About Sika Sikafloor-291
Sikafloor-291 sits in a very specific place in the flooring build-up: it is not the floor you walk on, it is the layer that makes the floor you walk on possible. Poured concrete rarely leaves site flat enough for a thin resin coating. Trowel marks, birdbaths, worn service areas and slight falls all telegraph straight through a 1-2 mm topping, so the industry standard is to first lay a levelling screed. Sikafloor-291 is Sika’s three-part, solvent-free epoxy answer to that problem, supplied as an 82 kg set of resin (Part A), hardener (Part B) and a graded off-white filler (Part C) that combine into a self-smoothing mortar at a 1:2.5:17 mixing ratio by weight.
Applied between 1.5 mm and 3 mm thick, it flows out to a fine-textured, matt, light-yellow surface that acts as the levelling and profiling course under Sika’s epoxy, polyurethane and PMMA systems, or under tiles, sheet vinyl, carpet and wood. Because it carries no solvent, it can be used in enclosed plant rooms and warehouses without the ventilation headaches of solvented screeds. Space Arc Engineering supplies and applies it across Delhi NCR and Pan-India as an authorised Sika distributor, typically as the middle step in a specified three-coat system: Sikafloor-290 primer, Sikafloor-291 levelling screed, then a Sikafloor-range wearing coat chosen for the traffic and chemical duty of the space.
The technical insight
The self-smoothing behaviour comes from the balance between the epoxy binder and the heavily loaded graded filler. Part C makes up the bulk of the mix (17 parts to every 1 part resin), so the material behaves like a flowable mortar rather than a thin coating: it has enough body to build 3 mm in a single pass yet enough flow to release trowel lines under its own weight. The epoxy resin cross-links with the hardener into a rigid, closely bonded matrix around those aggregates, which is why the cured screed reaches roughly 60 N/mm2 in compression and bonds to the slab above 1.5 N/mm2 in tension (failure occurs in the concrete, not the interface). The spiked roller step is not cosmetic. Mixing entrains air, and trapped bubbles become weak points and pinholes that would blister a subsequent vapour-tight topcoat, so rolling drives that air out before the epoxy gels. Pot life is the constraint that governs the whole operation: at +30 degC you have only about 10 minutes of working time before the exotherm stiffens the batch, versus around 40 minutes at +10 degC, which is why batch size and gang timing are planned around substrate temperature.
Where it is used
- Levelling and reprofiling concrete slabs before Sika epoxy, polyurethane or PMMA floor coatings and screeds
- Substrate preparation under ceramic and stone tiling in industrial and commercial kitchens
- Smoothing base course beneath sheet vinyl, linoleum and carpet in offices, hospitals and clean areas
- Correcting worn, uneven or trowel-marked floors in existing warehouses and factories before a new resin finish
- Building a flat, defect-free deck under wooden and laminate floor finishes
- Floor topping in back-of-house and plant rooms where a fine-textured surface without aesthetic requirements is acceptable
- Filling and levelling ahead of thin high-build coatings in pharmaceutical and food-processing facilities
- Reprofiling to correct minor falls and low spots in loading bays and circulation zones
Key advantages
- Solvent-free formulation suits enclosed plant rooms, basements and warehouses with limited ventilation
- Self-smoothing flow releases trowel marks and levels the slab in a single 1.5-3 mm pass
- Strong early and final mechanicals, reaching roughly 60 N/mm2 compressive strength at 28 days
- Bonds hard to prepared concrete, above 1.5 N/mm2 in tensile adhesion with failure in the substrate
- Economical filler-loaded mix covers large floor areas at a lower cost per square metre than a full epoxy screed
- Compatible base for the full Sikafloor range, so the levelling course and topcoat come from one system
- Fast enough turnaround to take foot traffic in around 7 hours at +30 degC
- Tested to Indian Standards (IS 9162-1979, IS 1237-1980) for abrasion and strength, easing specification in Indian projects
Limitations & considerations
- It is a levelling underlay, not a wearing surface, and its textured finish stains easily unless sealed with a Sikafloor topcoat
- Improved chemical resistance over bare concrete but not a chemical protection layer, so aggressive duty needs a resistant overcoat
- Restricted to 1.5-3 mm per application; deeper reprofiling or heavy build-up needs a different Sika screed
- Short pot life in Indian summer conditions (about 10 minutes at +30 degC) demands disciplined batching and gang work
- Requires mechanically prepared, sound concrete of at least 25 N/mm2 with substrate moisture at or below 4 percent
- For experienced professional applicators only, and adding water to ease flow will discolour and weaken the surface
Selection & best practice
Prepare the concrete mechanically by abrasive blasting or scarifying to remove laitance and open the surface, then vacuum off all dust. Confirm the slab is sound (minimum 25 N/mm2 compressive, 1.5 N/mm2 pull-off) and that moisture is at or below 4 percent by Tramex, CM or oven-dry method, with no rising damp. Prime with Sikafloor-290 at 0.2-0.3 kg/m2 and respect the overcoat window before laying 291. Work between +10 and +30 degC ambient and substrate, at 80 percent RH maximum, keeping the substrate at least 3 degC above dew point to avoid blooming. Shake A and B, mix for three minutes, then add C gradually with a slow-speed (300-400 rpm) helical paddle for a further three minutes; never use a free-fall mixer. Spread to 1.5-3 mm with a trowel and immediately de-aerate with a spiked roller, maintaining a wet edge for a seamless result. Size batches to the pot life at site temperature, and clean tools with water before the material cures.
Specifications
| Chemical base | 3-component solvent-free epoxy self-smoothing underlay / levelling screed |
| Mixing ratio (A:B:C by weight) | 1 : 2.5 : 17 |
| Packaging | 82 kg set (Part A 2 kg x2, Part B 5 kg x2, Part C filler 34 kg x2 HDPE) |
| Consumption | 2.2 kg per mm per m2 (plus Sikafloor-290 primer at 0.2-0.3 kg/m2) |
| Layer thickness | 1.5 mm min. / 3.0 mm max. |
| Compressive strength | ~60 N/mm2 (28 days / +27 degC, IS 9162-1979) |
| Flexural strength | ~18 N/mm2 (28 days / +27 degC, IS 9162-1979) |
| Tensile adhesion strength | >1.5 N/mm2, failure in concrete (ISO 4624) |
| Abrasion resistance | ~0.7 mm thickness loss (IS 1237-1980 & IS 9162-1979) |
| Pot life | ~40 min at +10 degC / ~20 min at +20 degC / ~10 min at +30 degC |
| Substrate moisture / RH | <=4% substrate moisture; 80% RH max; substrate & ambient +10 to +30 degC |
| Shelf life | 12 months (Parts A & B); 9 months (Part C) from date of production |
Industry use cases
Industrial and warehouse flooring
Levels worn, trowel-marked and slightly falling slabs across large factory and warehouse bays so a thin epoxy or PU wearing coat lands flat and defect-free.
Pharmaceutical and food processing
Provides the smooth, solvent-free base course under hygienic epoxy or PMMA finishes in production halls, kitchens and clean areas.
Healthcare and institutional
Smooths concrete decks ahead of sheet vinyl, linoleum or seamless resin in hospitals, labs and educational buildings where floor flatness matters.
Commercial fit-out and retail
Reprofiles existing floors before tiles, carpet or wood so finishes sit true, ideal for refurbishment where the old slab is uneven.
Plant rooms and back-of-house
Serves as a quick, economical fine-textured topping in service areas where a level, sound surface is needed but appearance is secondary.
Frequently asked questions
Is Sikafloor-291 a finished floor I can walk on directly?
How thick can I lay it in one pass?
What is the coverage per set?
Do I need a primer under it?
What condition does the concrete need to be in?
How long before I can overcoat or open the floor?
How we position Sika Sikafloor-291
Sikafloor-291 is the levelling step in a Sika system, not a standalone floor. Pair it with Sikafloor-290 as the mandatory primer beneath it, then finish with a Sikafloor-range wearing coat matched to the space, a self-levelling epoxy such as Sikafloor-263 SL for general industrial duty, or a PU/PMMA system where flexibility or fast turnaround is needed. For repairing blowholes and defects in the slab before levelling, the Sikadur and Sikagard ranges are the companion products Sika specifies. Where a client is standardised on Fosroc rather than Sika, the equivalent build uses a Fosroc epoxy underlay under a Nitoflor topping. Across our other lines, Dr. Fixit and MC-Bauchemie offer cementitious self-levelling underlayments when the project does not warrant an epoxy screed and a faster, lower-cost level is acceptable.
Fosroc Nitoflor EU5 — Choose the Fosroc high-strength self-smoothing epoxy underlay when the project is standardised on the Nitoflor system, as it fills the same levelling role beneath epoxy screeds, toppings and coatings at a comparable 1.5-5 mm build.
Related Industrial Flooring products
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Authorised distribution, technical advice & professional application across Delhi NCR and Pan-India.