Fosroc Conplast F297
A surfactant-based foam cement admixture used with foam-generating equipment to produce stable, lightweight foamed mortars for trench reinstatement, roofing screeds and void filling.
What is it?
Fosroc Conplast F297 is a foam cement admixture — a concentrated aqueous solution of selected surfactants that produces a stable pre-foam capable of surviving the alkaline conditions of cement mortars. It is used to manufacture foamed low-density mortars.
Where is it used?
Foamed low-density mortar applications across India: trench filling for road reinstatement, lightweight roofing screeds, and filling voids such as old sewers and disused solvent tanks.
Why use it?
It creates a stable air-foam structure that lets you produce controlled low-density mortars (1500 down to 600 kg/m3), reducing dead load and material volume while delivering flowable, self-levelling, easily placed fill.
How is it applied?
Dosed at 0.6 to 2.0 litres of undiluted material per cubic metre of finished mortar and used with approved foam-generating equipment, which blends the pre-foam into the cement mortar mix on site.
About Fosroc Conplast F297
Space Arc Engineering supplies Fosroc Conplast F297, a foaming agent for cementitious mortars supplied as a concentrated surfactant solution that is diluted with water and passed through approved foam-generating equipment to produce a stable pre-foam. What matters about that pre-foam is durability inside the mix: it is engineered to survive the highly alkaline conditions of fresh cement mortar rather than collapsing on contact, holding its bubble structure long enough for the mortar to set and lock in a controlled, lightweight cellular matrix.
Importantly, Conplast F297 is NOT an air-entraining admixture and NOT a freeze-thaw concrete admixture. It is a foaming agent for making foamed low-density mortars — an entirely different product category from air-entrainers used in structural concrete. Where an air-entrainer introduces a small, measured percentage of microscopic air for durability, Conplast F297 generates a large, deliberate volume of stable foam to slash the density of the finished mortar.
In Indian construction, foamed mortars made with Conplast F297 are valued wherever a flowable, self-levelling, low-load fill is needed. Typical uses include trench filling for road and utility reinstatement (so the trench can be reinstated quickly and uniformly), lightweight roofing screeds that reduce dead load on the slab, and filling abandoned voids such as old sewers and disused solvent tanks. By adjusting the foam content, finished mortar densities can be produced across a range of approximately 1500 to 600 kg/m3, letting site teams dial in the balance of weight, flow and fill economy the job requires.
Space Arc Engineering supplies Conplast F297 as an authorised Fosroc distributor and applicator serving Delhi NCR and Pan-India, with technical support on dosage, equipment and mix design for foamed-mortar works.
The technical insight
Conplast F297 works by surfactant chemistry, not by entraining incidental air. The selected surfactants reduce surface tension so that air can be mechanically whipped into a stable pre-foam by foam-generating equipment; the foam is then blended into the cement mortar. Because cement pore water is strongly alkaline, ordinary foams break down quickly — Conplast F297 is engineered so its bubble walls remain intact through mixing, placing and the early set, producing a uniform closed-cell structure in the hardened mortar. This is what allows finished densities to be controlled from roughly 1500 down to 600 kg/m3. The product is water-based and non-flammable. A practical limitation to respect on site is temperature: the material (or its dilutions) should not be allowed to cool below 10C, as this reduces foaming effectiveness, and wash water or water that is high in calcium ions should be avoided in the mix, since hard/contaminated water can destabilise the foam. It is compatible with Portland cement.
Where it is used
- Trench filling for road reinstatement, where a flowable low-density mortar reinstates the trench quickly and uniformly
- Lightweight roofing screeds that reduce dead load on the structural slab
- Filling abandoned or disused voids such as old sewers
- Filling decommissioned solvent tanks and similar buried voids
- General foamed low-density mortar production where reduced density and self-levelling flow are required
Key advantages
- Produces a stable foam that survives the alkaline conditions of cement mortars, unlike ordinary foaming agents
- Enables controlled finished mortar densities across approximately 1500 to 600 kg/m3 by adjusting foam content
- Significantly reduces dead load and material volume, ideal for roofing screeds and large void fills
- Yields a flowable, self-levelling foamed mortar that is easy to place and reaches into awkward voids
- Water-based and non-flammable, simplifying storage and site handling
- Compatible with Portland cement, fitting standard site mix practice
- Long shelf life of at least 12 months when stored correctly
Limitations & considerations
- Requires approved foam-generating equipment — it cannot simply be added to a concrete mixer like a conventional admixture
- Not an air-entraining admixture and not intended for freeze-thaw durability in structural concrete; it is strictly a foaming agent for low-density mortars
- Foaming effectiveness drops if the material or its dilutions are allowed to cool below 10C
- Wash water and water high in calcium ions should be avoided, as hard or contaminated water can destabilise the foam
- Foamed low-density mortar is a fill / screed material, not a structural load-bearing concrete
Selection & best practice
Use Conplast F297 only with approved foam-generating equipment and dose at 0.6 to 2.0 litres of undiluted material per cubic metre of finished mortar, selecting the rate that gives your target density within the 1500-600 kg/m3 range. Keep the material and any dilutions above 10C to preserve foaming effectiveness, and mix with clean potable water — avoid wash water and water high in calcium ions. Confirm compatibility is with Portland cement, store drums between 10C and 50C, and use within the 12-month shelf life. For trial mixes, density verification and equipment guidance, consult Space Arc Engineering’s technical team.
Specifications
| Product type / chemical base | Foam cement admixture; concentrated solution of selected surfactant (water-based) |
| Primary use | Production of foamed low-density mortars — trench filling for road reinstatement, lightweight roofing screeds, filling voids (old sewers, solvent tanks) |
| Dosage | 0.6 to 2.0 litres of undiluted material per cubic metre (m3) of finished mortar |
| Resulting mortar density range | 1500 to 600 kg/m3 |
| Flammability | Water-based, non-flammable |
| Temperature limitation | Do not dilute with or allow dilutions to cool below 10C (reduces foaming effectiveness); avoid wash water / water high in calcium ions |
| Compatibility | Compatible with Portland cement |
| Packaging | 25 litre and 210 litre drums |
| Shelf life | Minimum 12 months stored between 10C and 50C |
Industry use cases
Roads & Highways
Trench reinstatement after utility works — foamed low-density mortar made with Conplast F297 flows into the trench and self-levels, allowing fast, uniform reinstatement of the carriageway.
Roofing & Building
Lightweight roofing screeds that cut dead load on the structural slab while still providing a sound, levelled substrate.
Infrastructure Decommissioning
Filling abandoned voids such as old sewers and disused solvent tanks with stable foamed mortar to stabilise the ground and eliminate void collapse risk.
Civil Works (General)
Any application calling for a controlled low-density, flowable fill where reducing weight and material volume is more important than structural strength.
Frequently asked questions
Is Fosroc Conplast F297 an air-entraining admixture for freeze-thaw concrete?
What is Conplast F297 actually used for?
What is the correct dosage?
What density of mortar can I achieve?
Are there temperature or water precautions?
How is it packaged and how long does it keep?
Where can I buy Conplast F297 in India?
How we position Fosroc Conplast F297
Fosroc Conplast F297 is the foaming agent of choice for producing stable foamed low-density mortars. Specifiers comparing options may also encounter foam concentrates such as Sika’s foamed-mortar / Aer-type foaming agents and BASF MasterCell-class products; within the Fosroc system, Conplast F297 is the dedicated surfactant-based foam admixture engineered to survive cement alkalinity and deliver controlled densities from 1500 to 600 kg/m3. Space Arc Engineering supplies it as an authorised Fosroc distributor and applicator for Delhi NCR and Pan-India.
Related Concrete Admixtures products
Source Fosroc Conplast F297 for your project
Authorised distribution, technical advice & professional application across Delhi NCR and Pan-India.