Insulate suspended floors and underfloor voids from beneath — sealing draughts and cold-bridging in awkward, hard-to-reach spaces.
Commercial ground floors and exposed soffits over unheated voids, plant rooms or open undercrofts lose heat steadily and invite condensation on the cold underside. Rigid boards are awkward to fit between irregular joists, beam-and-block or steel deck profiles, leaving gaps at every junction. Suspended timber and access floors are even harder to seal, so draughts track up through the floor zone into occupied space above.
Enverge closed-cell spray foam is applied to the underside of the floor structure or within the floor void, expanding into every profile and junction before curing rigid. It self-bonds to concrete, timber and steel as it sets, forming a continuous insulating and air-sealing layer with no cut-to-fit gaps. Its low water permeability also keeps the cold underside dry, removing the surface where condensation would otherwise form.
The result is a warmer, draught-free floor plate with stable surface temperatures and no damp underside. Heating loads drop, comfort improves in the space above, and the structure is protected from moisture — achieved without lifting finished floors or disrupting the occupied levels overhead.
Seals the cold underside so heat is retained and surface temperatures stay stable in the occupied space above.
Expands into beam-and-block, steel deck and timber joist junctions that rigid boards can never close fully.
Low-permeability foam keeps the cold soffit dry, removing the surface where condensation forms over voids.
Continuous air seal blocks the draughts that track up through suspended and access-floor zones.
Self-adheres to concrete, steel and timber as it cures — no fixings, no slumping over the floor span.
Applied from below, so finished floors and occupied levels above stay undisturbed during works.
Closed-cell foam bonds to joists and the floor underside, sealing draughts and cold-bridging even where access is restricted.
Sprayed to the floor soffit or into the void, Enverge closed-cell foam expands into joist, deck and beam-and-block profiles, then cures to a rigid layer that self-bonds to the structure. Its closed-cell matrix combines thermal resistance with low moisture permeability, raising underside surface temperatures and removing the cold, damp-prone face above unheated voids and undercrofts.
Typical published values for Enverge Nexseal LE closed-cell foam. Full technical specification →
Below-ground and underfloor spaces are hostile to boards: irregular pile faces, tight crawl voids and damp-prone surfaces leave gaps everywhere. Sprayed closed-cell foam is applied at 25–100 mm directly onto the irregular surface — sheet piling, retaining walls, blockwork or floor joists — sealing cold bridging and carrying its own vapour barrier.
Because the applicator sprays in-situ, compromised voids that could never be boarded out are insulated completely, sealing draughts up into the building and bringing the below-ground envelope up to specification in a single visit.
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Free survey of your suspended floors & condensation check.
The right system for your suspended floors.
Approved applicators, minimal disruption.
Handover pack & 25-year warranty.
Underside of a car-park deck sealed and insulated in-situ.
Concrete soffit spray foam eliminating cold-bridging.
Cavity-filling spray foam for an airtight commercial partition.
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Yes. Enverge closed-cell foam is sprayed to the underside of the floor structure from the void or undercroft below, so the finished floor and occupied levels above stay undisturbed. It seals into joists, beams and deck profiles in one continuous application.
Closed-cell foam is low-permeability and raises the underside surface temperature, removing the cold face where condensation collects. By sealing air paths and insulating the soffit together, it keeps the structure dry over unheated voids, plant rooms and open undercrofts.
Yes. The foam expands into the irregular profiles of beam-and-block, profiled steel deck and timber joist floors, bonding as it cures. This closes the junction gaps that rigid boards leave open, giving a continuous thermal and air-tight layer across the whole soffit.
Once cured, the closed-cell foam is rigid and durable, well suited to exposed soffits in voids, undercrofts and plant areas. Where the underside is publicly accessible or fire performance is required, a protective coating can be specified over the foam.
Very little — work is carried out from below in the floor void or undercroft, so occupied space overhead keeps running. We contain overspray, manage access and ventilation, and phase the work to minimise any impact on the building above.
Usually yes — spray application needs far less working room than boarding out, and the foam seals surfaces boards can't reach.
No — closed-cell foam has an integral vapour barrier, one of the reasons it's specified below ground.
Typically 25–100 mm depending on the target U-value and the structure — specified after survey.
Specialist commercial spray foam, installed UK-wide by the Duratite Group's spray foam specialists.
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