Sika Colma Coat
Anti-Evaporation and Curing Coat for Fresh Concrete and Mortar Surfaces
Authorized Project Distributor — Sika India | Space Arc Engineering, Ghaziabad
Product Overview
Sika Colma Coat is a water-based, sprayable anti-evaporation agent and temporary curing compound designed to protect freshly placed concrete and mortar surfaces from premature moisture loss in the critical period between concrete placement and the application of a permanent curing membrane or covering. When sprayed onto a freshly levelled and finished concrete surface, Sika Colma Coat forms a thin, transparent film on the concrete surface that drastically reduces the rate of surface evaporation. This is particularly critical on large concrete floor slabs, pavements, airport aprons, road slabs, and roof decks where the concrete surface area is very large relative to the volume of concrete, and where the risk of plastic shrinkage cracking is highest. Plastic shrinkage cracking occurs when the rate of surface evaporation exceeds the rate at which bleed water rises to the surface — typically in hot weather, low relative humidity, or windy conditions common in Delhi NCR summers. Once plastic shrinkage cracks form (typically as a network of random shallow cracks 30 to 60 minutes after concrete placement, before the concrete has any tensile strength), they are permanent defects that reduce durability and aesthetics. Sika Colma Coat acts as a sacrificial evaporation barrier that buys time for bleed water to reach the surface and sustain surface moisture until proper curing can be established. Unlike conventional curing compounds that must remain on the surface for the full curing period, Sika Colma Coat can be used as a temporary anti-evaporation agent followed by conventional wet curing or a permanent curing compound. It is also fully compatible with subsequent application of Sika Antisol curing compounds, floor coatings, and toppings without the need for removal. Space Arc Engineering supplies Sika Colma Coat for large slab concrete construction, road and pavement works, and industrial flooring projects across Delhi NCR and Uttar Pradesh where hot weather concreting is a critical challenge.
Applications
- Fresh concrete floor slabs — large warehouse, industrial floor, and commercial building ground floor slabs
- Road and highway concrete pavements — anti-evaporation during and after finishing
- Airport apron, taxiway, and runway concrete slabs — wind and heat evaporation protection
- Precast concrete element faces — prevent surface drying before curing can be applied
- Roof slab concrete — anti-evaporation on exposed horizontal surfaces
- Fresh shotcrete and sprayed concrete surfaces — prevent rapid surface drying
Key Advantages
- Prevents plastic shrinkage cracking — the most common fresh concrete defect in hot Delhi NCR summers
- Transparent film — does not obscure fresh concrete surface for levelling and finishing operations
- Fast and simple spray application — covers large floor areas rapidly before surface sets
- Compatible with subsequent curing compounds, floor hardeners, and coatings — no removal required
- Water-based, non-toxic formulation — safe for use in enclosed areas and by unprotected applicators
- Buys time for bleed water rise on large slabs in high evaporation conditions
Technical Data
| Type | Water-based anti-evaporation and temporary curing agent |
| Form | Liquid for spray application |
| Film | Transparent — does not affect surface appearance or finish operations |
| Application Method | Low-pressure garden sprayer or pump sprayer on fresh concrete surface after final finishing |
| Coverage | Approximately 4 to 6 m2 per litre depending on surface porosity and spray equipment |
| Compatibility | Compatible with Sika Antisol curing compounds, floor hardeners, and subsequent coatings |
Get a Quote
+91 9999155255 | info@space-arc.com | Space Arc Engineering, Sahibabad, Ghaziabad
Frequently Asked Questions
When exactly should Sika Colma Coat be applied on a fresh concrete slab and how does application timing affect its effectiveness?
The timing of Sika Colma Coat application on a fresh concrete slab is critical to its effectiveness in preventing plastic shrinkage cracking. Sika Colma Coat must be applied immediately after the final finishing operation on the concrete surface — typically within 5 to 15 minutes of screeding, power trowelling, or bull-floating on each section of the slab. The product must not be applied until the final pass of the float or trowel is complete on that section, because any float or trowel pass after Sika Colma Coat application will break the evaporation-resistant film and negate its effect. On large slabs poured in bays or strips, this means Sika Colma Coat should be applied in a rolling sequence immediately behind the finishing crew — first bay finished, Colma Coat sprayed, move to next bay. On slabs with multiple finishing passes (e.g., initial levelling, then power-float for flat floor warehouse construction), Sika Colma Coat can be applied between passes as an intermediate anti-evaporation coat to protect the surface during the waiting period between finishing operations. Apply as a uniform fine mist spray at the prescribed coverage rate — do not apply in a single heavy coat (which wastes product and can cause runs on inclined surfaces). On windy days, apply immediately after the finisher moves away from each section and shield the spray application from the wind where possible. In extreme evaporation conditions (temperature above 35 degrees C, wind speed above 20 km per hour, relative humidity below 40 percent — all typical of Delhi NCR May and June afternoons), Sika Colma Coat alone may not be sufficient to prevent plastic shrinkage cracking: also erect windbreaks around the slab perimeter, schedule the pour for early morning or overnight, and pre-cool the concrete mix and aggregates.
Can Sika Colma Coat be used as a permanent curing compound to comply with IS 456 concrete curing requirements or is it only a temporary anti-evaporation agent?
Sika Colma Coat is primarily an anti-evaporation agent for use in the plastic concrete phase and as a temporary curing coat. It is not a permanent curing compound and should not be used alone as the sole method of curing to meet IS 456 requirements for minimum curing duration and efficiency. IS 456:2000 specifies a minimum curing period of 7 days for ordinary Portland cement concrete (and 10 to 14 days for blended cement concrete with GGBS or fly ash) at temperatures above 5 degrees C. Sika Colma Coat provides effective anti-evaporation protection for the first few hours after placing — up to approximately 4 to 6 hours at normal temperatures — after which the film breaks down or is dissipated and no longer provides a meaningful moisture-retaining function. For IS 456 compliant curing: apply Sika Colma Coat immediately after finishing to prevent plastic shrinkage cracking (this is the primary purpose), then follow with one of the following permanent curing methods within 4 to 6 hours: wet curing using wet hessian burlap covered with polythene sheet, maintained wet for the full IS 456 minimum curing period; or apply Sika Antisol curing compound (a properly formulated permanent curing compound that meets ASTM C309 efficiency requirements) at the specified coverage rate as the permanent curing treatment. Sika Colma Coat is fully compatible with Sika Antisol curing compounds and with wet curing — it does not need to be removed before Sika Antisol application. The correct sequence is: concrete placed and finished, Sika Colma Coat sprayed immediately, wet hessian or Sika Antisol applied within 4 to 6 hours.
Source Sika Colma Coat for Your Project
Space Arc Engineering is an Authorized Project Distributor for Sika India serving Delhi NCR, Ghaziabad, Noida and Uttar Pradesh.
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