About Fosroc Concure LP90

Fosroc Concure LP90 is a polymer resin dissolved in solvent that is sprayed onto green concrete as soon as final finishing is complete. As the solvent flashes off, the resin knits into a thin, continuous film that clings to the surface and blocks evaporation. That barrier holds the mix water inside the slab where it is needed, so the cement can hydrate fully in the critical first days rather than losing moisture to sun and wind. The result is a denser, harder, more abrasion-resistant top layer with far less risk of early plastic-shrinkage and drying-shrinkage cracking.

For Indian sites, the appeal is practical. Water curing a large floor or pavement means labour, hoses, ponding bunds and constant supervision, and it is nearly impossible to keep a big pour uniformly wet through a hot afternoon. LP90 replaces all of that with one spray pass. It is supplied in a Clear grade and a Blue grade that carries a fugitive dye so the applicator can see exactly where the membrane has landed and avoid holidays. Space Arc Engineering stocks and applies Concure LP90 as an authorised Fosroc channel across Delhi NCR and pan-India, and can advise where the solvent-based LP90 is the right call versus a water-based alternative.

The technical insight

Concrete gains strength through hydration, a reaction that needs the mix water to stay in the matrix for the first several days. On an exposed slab, surface water evaporates faster than bleed water can rise, the top skin dries out prematurely, and you get a weak, dusty, crack-prone surface even though the core is sound. Concure LP90 works by physics, not chemistry with the concrete: the dried resin film is a low-permeability membrane that throttles evaporation, so the surface stays saturated long enough for the cement paste to develop dense hydration products. Independent testing to BS 7542 rates this class of membrane at roughly 90% curing efficiency, meaning it retains about nine-tenths of the moisture that an uncured control slab would have lost. Because the film sits on top and does not penetrate, it also gives a measure of early protection against light rain and site traffic while curing proceeds. The Blue grade’s fugitive dye is a deliberate quality-control aid, and being solvent-carried, LP90 sets its film quickly even in humid conditions where water-based emulsions can be slow to break.

Where it is used

• Curing large-area ground-floor and suspended concrete slabs
• Highway, road and hardstanding concrete pavements
• Airport runways, taxiways and aprons
• Bridge decks and other infrastructure pours
• Industrial and warehouse floor slabs before finishing
• Precast and prestressed concrete elements
• Canal linings, reservoirs and water-retaining structures
• Any large pour where conventional water curing is impractical

Key advantages

• Retains around 90% of mix water for efficient cement hydration (BS 7542)
• Single spray coat replaces hessian, ponding and continuous water curing
• Cuts labour, water use and site supervision on large pours
• Reduces plastic-shrinkage and drying-shrinkage cracking
• Produces a denser, harder, more abrasion-resistant surface
• Blue grade’s fugitive dye makes coverage visible and holidays easy to spot
• Solvent carrier lets the film form quickly, even in humid weather
• Good coverage of 3.5-5.0 sq.m per litre keeps material cost predictable

Limitations & considerations

• Solvent-based and flammable – needs ventilation, no naked flames, and care in enclosed spaces
• The dried film usually must be removed before applying tile adhesive, screeds, coatings or bonded toppings
• Not a waterproofer, hardener or admixture – it only aids curing, it does not add strength on its own
• Must be sprayed at the right moment (once surface sheen goes); too early and it disturbs the finish, too late and evaporation has already begun
• Coverage varies with surface texture, so porous or tined surfaces consume more per litre
• On vertical or overhead work the film is less suited than to horizontal slabs

Selection & best practice

Specifications

Industry use cases

How we position Fosroc Concure LP90

Concure LP90 sits in the Fosroc Concure curing-compound family alongside the water-based Concure WB and the aluminised Concure LP90(M). Choose LP90 for fast film formation and reliable ~90% curing efficiency on horizontal slabs and pavements; step up to LP90(M) where its silver, light-reflective film helps beat solar heat gain on exposed decks. Where solvent flammability or indoor ventilation is a concern, Fosroc Concure WB is the water-based alternative. Remember LP90 only cures – it is not a waterproofer or a hardener: for integral waterproof concrete pair it with a Fosroc Conplast admixture (such as Conplast WL or WP90), and where a genuine surface hardener/dustproofer is the goal, that is a different product class we can also supply. Space Arc Engineering stocks the full Fosroc curing and admixture range and can cross-match the right system for the pour.

Related Industrial Flooring products

View all Industrial Flooring products →