About Fosroc Nitocote ET84

Fosroc Nitocote ET84 is a liquid-applied protective and waterproofing coating based on an acrylic-modified bituminous binder. On Fosroc’s official catalogue it is described as a “revestimiento de brea acrilica para impermeabilizacion” – an acrylic-bitumen coating for waterproofing – and it sits within the wider Nitocote family of protective coatings that Fosroc markets for corrosion control and concrete protection. The product is supplied in Fosroc’s Iberia and Latin American ranges; it is the kind of barrier coating Indian contractors will recognise alongside Fosroc’s locally familiar Nitoproof bituminous range. Once cured, ET84 leaves a tough, adherent film that seals the surface against water, water vapour and a range of aggressive agents. The intent is straightforward but important on a construction site: stop water and chemically aggressive ground or process liquids from reaching the concrete or steel beneath, because it is that ingress which drives reinforcement corrosion, spalling and premature structural deterioration. For consultants and engineers, ET84 belongs in the “protect the substrate” toolbox rather than the decorative or structural-repair toolbox – it is a sacrificial-free, in-service barrier layer that does its work quietly behind backfill, below grade or inside a wet structure. Because it is bitumen-based, it is black and opaque, and it is most at home in concealed or buried locations rather than exposed architectural faces. Space Arc Engineering positions ET84 for project teams who need a dependable damp-proofing and anti-corrosion film on foundations, water-retaining and water-excluding structures, and steel that will spend its life in damp or chemically loaded environments.

The technical insight

The defining feature of Nitocote ET84 is its acrylic-modified bitumen chemistry. Straight bitumen coatings are cheap and waterproof but can stay thermoplastic – soft when warm, brittle when cold – and can re-emulsify under prolonged water contact. Blending acrylic polymer into the bitumen raises the bar: the film toughens, adhesion and cohesion improve, water absorption drops, and the coating better resists abrasion and the chemical attack typical of effluent and ground water. That is exactly the combination Fosroc lists for ET84 – good abrasion resistance, good chemical resistance, minimal water absorption and good adhesion. For a protective coating, low water absorption is the single most useful property, because the coating’s job is to keep the chloride-, sulphate- and CO2-laden moisture front away from embedded steel; an acrylic-bitumen film resists that front far longer than an unmodified emulsion. The practical engineering reading is that ET84 is a barrier coating, not a crack-bridging elastomeric membrane and not a chemically-cured epoxy lining. It will follow the durability logic of BS 8102 (protection of below-ground structures) and BS 8500 / IS 456 thinking on cover and protection to reinforcement – the coating extends the time before the environment reaches the steel, but it does not replace adequate cover, sound concrete or good detailing. Engineers should treat the published dry film thickness on the current TDS as the controlling specification value and verify it on site, because barrier performance is thickness-dependent.

Where it is used

• Waterproofing and damp-proofing of buried footings, pile caps and foundation faces, including wind-turbine and heavy-plant footings
• Protection of below-ground retaining walls and basement/underground walls before backfilling
• Bridge deck waterproofing and protection of associated concrete substructure
• Corrosion protection of iron and steel elements exposed to damp or aggressive ground/process conditions
• Protection of water and effluent structures – wastewater and sewage treatment plants, sumps, receiving tanks and reservoirs
• Lining and protection of swimming pools and storage/receiving tanks against water and mild chemical attack
• Barrier coating on cementitious render and concrete in chronically damp or splash-zone locations

Key advantages

• Acrylic modification gives a tougher, better-adhering film than plain bitumen emulsion
• Minimal water absorption keeps the aggressive moisture front away from concrete and steel
• Good chemical resistance suits wastewater, effluent and buried environments
• Good abrasion resistance helps the film survive backfilling and handling
• Bonds well to concrete, cementitious render, iron and steel
• Liquid-applied by brush, roller or spray, so it follows complex shapes and detailing seamlessly with no laps or joints
• Cold-applied barrier coating – no hot works, unlike torch-applied bituminous membranes
• Backed by Fosroc’s global protective-coatings range and TDS/SDS documentation

Limitations & considerations

• Bitumen-based and black/opaque – not suitable as a decorative or light-coloured architectural finish
• A barrier coating, not a crack-bridging elastomeric membrane – it will not span moving or future cracks on its own
• Not a chemically-cured epoxy/polyurethane lining; for strong-chemical immersion duty an epoxy such as Nitocote EP405/EPS may be more appropriate
• Performance depends on achieving the specified dry film thickness and full, pinhole-free coverage
• Requires a clean, sound, dry and properly primed substrate; poor surface prep undermines adhesion
• Primarily catalogued in Fosroc’s Iberia/Latin America range, so India project teams should confirm current local availability, exact specification and approved primer with Fosroc before specifying
• Not intended for potable-water contact unless the current TDS and local approvals explicitly permit it
• Like most bituminous coatings, prolonged UV exposure on permanently exposed surfaces is best avoided or over-coated

Selection & best practice

Specifications

Industry use cases

How we position Fosroc Nitocote ET84

Within Fosroc’s own range, Nitocote ET84 sits between the company’s plain bituminous waterproofers and its higher-performance reactive coatings. For straightforward below-ground damp-proofing and concrete protection, Indian project teams will most often see Fosroc’s locally stocked Nitoproof bituminous products (such as Nitoproof 100 and Nitoproof 120, the latter referenced to BS 8102) and the bitumen coating Nitocote EB83 – all close cousins to ET84 in role. When the duty is harsher – immersion in strong chemicals, ground-gas protection or high-build epoxy lining – Fosroc’s Nitocote EP405 and Nitocote EPS epoxy coatings, or the elastomeric cementitious Nitocote CM210 for water-retaining structures, are the step up, and ET84 should not be substituted for them. Against the wider Indian market, ET84 competes with bituminous and acrylic-bituminous protective coatings from Sika (e.g. Sika bituminous coatings and Sikaproof membranes), MBS (MYK Arment) protective and waterproofing coatings, Dr. Fixit’s bitumen-based damp-proofing products from Pidilite, and STP Limited’s long-established bituminous coating and membrane range. The honest positioning is that ET84 is a competent, Fosroc-backed acrylic-bitumen barrier coating best chosen when you already specify Fosroc systems and want range consistency and single-source technical support; for a like-for-like Indian job, an equivalent Sika, MBS, Dr. Fixit or STP bituminous coating can deliver comparable barrier performance, and the decision usually turns on local availability, approved-applicator support, project specification and price. Space Arc Engineering’s role is to match the right barrier or membrane to the exposure – confirming the current Fosroc TDS, recommending the correct primer and, where ET84 is not the best local fit, proposing the closest verified alternative.

Related Protective Coatings products

View all Protective Coatings products →