The challenge
Nissen huts have a continuous curved corrugated steel shell with no flat planes, and the thin metal conducts heat and cold rapidly. In a food-production setting, warm internal air meeting the cold steel arch generates condensation across the whole roof, which drips and creates a damp environment unsuited to the hygiene demands of a creamery.
The curved corrugated profile is exactly the geometry that rigid board insulation cannot follow. Boards cannot be shaped to the arch or sealed against the corrugations without leaving voids and cold bridges, so condensation persists. The building needed a continuous insulating layer that could conform to the curve and seal the steel completely.
The ThermoFoam solution
ThermoFoam specified Enverge Nexseal LE closed-cell spray foam, applied directly to the inside of the curved steel shell. As it cures, the foam self-bonds to the corrugated metal and follows the full arc of the roof, filling every corrugation to form one seamless insulating layer without fixings or boards.
The closed-cell foam provides both insulation and vapour resistance, raising the steel's inner surface temperature above the dew point so warm air no longer condenses on the cold metal. Its sprayed application conforms perfectly to the Nissen hut curve, sealing the shell where no board system could.
The result
The curved steel roof was given a continuous, conforming layer of closed-cell insulation that controlled the condensation and improved the thermal performance of the hut for food-production use. The work met the manufacturer-certified standard and carries the manufacturer-backed product warranty.
