Commercial underfloor and soffit spray foam insulation across London — closed-cell Enverge foam insulates suspended floors, basements and undercrofts on access-constrained city sites, cutting heat loss and cold-floor complaints in occupied buildings.

Across London's commercial and industrial stock, suspended ground floors, basement ceilings and undercrofts lose heat into cold, ventilated voids beneath the occupied space. The result is cold floors, uneven comfort and wasted energy in offices, retail units and warehouses. Insulating the underside of the structural deck tackles this directly — and spray foam reaches the awkward soffits, beam flanges and service-crowded undersides that board systems struggle to cover cleanly.
Closed-cell Enverge foam is sprayed up onto the floor soffit, where it self-bonds to the deck as it cures and expands to seal around pipework, ducts, hangers and steel beams in a single continuous layer. There are no boards to cut around services, no fixings into the deck and no gaps at junctions — just an unbroken thermal blanket on the underside that lifts floor surface temperatures and curbs heat loss from the rooms above.
London sites bring their own constraints: live tenants overhead, restricted access through basements and undercrofts, limited working windows and tight delivery logistics in the city. ThermoFoam plans around them — phased, out-of-hours or sectional work to keep premises trading — and the Duratite Group delivers the same specification UK-wide, so multi-site London estates and national portfolios get one consistent underfloor insulation standard.
Phased, out-of-hours and sectional working keeps occupied London premises trading while floors are insulated from below.
Insulating the soffit lifts floor surface temperatures, cutting cold-floor complaints in offices, retail and warehouse units.
Foam expands around pipes, ducts, hangers and beams in one pass — no boards to cut around congested soffits.
Self-bonds to the underside of the structural floor as it cures, with no fixings drilled into the slab or beams.
A continuous sprayed layer seals the air paths through cold undercrofts and basements that chill the rooms above.
The Duratite Group delivers the same standard nationally, ideal for London estates and multi-site portfolios.
London commercial buildings often have suspended floors, undercrofts and basement soffits exposed to cold, unheated voids below. We spray closed-cell Enverge foam to the underside of the structural deck, where it self-bonds and seals around services and steelwork — working within the tight access and out-of-hours constraints typical of occupied city premises.
Closed-cell Enverge foam is spray-applied to the soffit of suspended floors and basement decks, self-bonding to the structure as it cures. It expands to seal around services and steelwork, forming a continuous, low-permeability layer that raises floor surface temperatures and reduces heat loss into cold voids below — with no boards, fixings or junction gaps.
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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Send us your building details and our technical team will specify the right system and a clear budget. No obligation.
Underside insulation avoids disturbing the occupied floor finish above and tackles heat loss at the cold void itself. Spraying the soffit reaches beams, hangers and service-crowded undersides cleanly, lifting floor surface temperatures without taking the space above out of use.
Yes. We plan around live tenants with phased, sectional or out-of-hours working, and coordinate basement and undercroft access and city delivery logistics so premises keep trading. The dry, fast-curing spray process suits tight working windows typical of occupied commercial sites.
Closed-cell foam expands to seal around services and beams in a single pass, so there's no cutting boards to fit congested undersides. It self-bonds to the deck and surrounding elements, leaving a continuous insulated layer with no gaps at junctions or penetrations.
London is a core service area, but the same specification is delivered UK-wide by the Duratite Group. That makes us a good fit for London estates and national portfolios that want one consistent underfloor and soffit insulation standard across every site.
The Enverge closed-cell system (Nexseal LE) is supplied with Duratite as UK distributor of record. It carries a 25-year manufacturer-backed product warranty — never insurance-backed — giving building owners and managers long-term assurance on the installed insulation.
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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