Commercial Spray Foam Insulation in March

Specifying spray foam for a building in March

A commercial installation in March is a specification job, not a product sale. What follows is what we actually look at, what we specify and how the work runs on site.

What we check before quoting

The substrate comes first. Corrugated fibre-cement, profiled steel, concrete soffit and timber all behave differently and each needs different preparation. We check for water ingress before anything else, because underside insulation is not a waterproofing system — a roof that leaks in the rain needs the leak dealt with first. We also record how the building is used and how much moisture is generated inside it, because condensation is driven as much by what happens under the roof as by the roof itself. Where the sheeting is asbestos-cement, encapsulation may be suitable: the material stays in place and remains subject to management.

The system we specify

Closed-cell Nexseal LE covers most commercial buildings we insulate in the East of England. Sprayed in place it self-bonds to the substrate and keeps the inner surface above dew point, which is what ends the drip and the corrosion that follows it; it also carries a 25-year manufacturer-backed product warranty. Where a building needs vapour to move more freely, open-cell Sucraseal is the specified alternative. The system and the thickness are both fixed in writing before work starts — see the guide to stopping condensation for how the two decisions interact.

How the installation runs

Work is phased around your operation. Areas are sheeted and protected, services and rooflights masked, and the foam applied in controlled passes to the specified thickness, with coverage checked before the protection comes down. Most buildings in March are sprayed in days rather than weeks and stay in use for much of it. You receive the specification, the product documentation and the warranty paperwork at handover.

What a job costs turns on area, specified thickness and access, which is why a figure before a survey is guesswork; the cost guide sets out the variables honestly. Send us the postcode, the roof type and rough dimensions to arrange a free survey in March.