Sprayfoam roof insulation West Sussex – case study

Installing roof insulation to an annexe and carport at a private residential address

Near Storrington, West Sussex

Construct 10 Ltd

Material used
BASF Elastospray sprayed closed cell foam

2 days

A developer of prestigious properties in the Chichester area and regular client, Construct 10 Ltd, contracted Isotech Sprayfoam to install closed cell insulation foam to the roof of a new build annexe and carport building adjacent to a residential property.

Annexe car port roof insulation external view


Closed cell foam offers superior insulation properties to alternatives such as open cell foam or mineral wool.

Traditional methods, such as cutting and installing Polyisocyanurate (PIR) insulation boards between the rafters, are time consuming and expensive.

Closed cell spray foam is exceptionally light, adheres evenly to the substrate and cures and sets within minutes.

To achieve the required level of airtightness and insulation at an appropriate cost, 150mm of foam was applied between the rafters, from the eaves to the ceiling line, to the underside of the breathable membrane installed by the roofing contractor.


Annexe roof insulation internal view - before foam applied
Annexe roof insulation showing foam applied around Velux window

The material is processed through a Gusmer proportioning pump fitted in our van. This machine is driven by compressed air from our towed compressor and requires an electricity supply to power switches and the internal heater block. A twin heated hose (210 feet maximum length) is fed from the van to the point of application. The two components mix at the tip of the spray gun under pressure and are reacting as they are applied to the roof or wall substrate. The flow of the rising foam seals gaps in the structure and has exceptional bonding characteristics. The closed cell foam sets hard in minutes with a core density of 32-36 Kg/m3. The depth of the foam can be varied from 25mm for anti-condensation treatments to in excess of 100mm, where very high levels of insulation are required.


Case Study

Any excess material from the spraying process was cut-back, and overspray was removed from the faces of the rafters. This allows the subsequent trade immediate access to complete the build.

Cured foam is deemed as non-hazardous and can be disposed of as general waste.

The entire process took two days from start to finish, keeping costs down while ensuring a warm roof with a low level of thermal conductivity, which will save energy and heating costs at the property for the life of the building.

For a free estimate call Isotech Sprayfoam on 023 9281 6291