Insulating concrete formwork (ICF)

Insulating concrete formwork is a simple construction system using purpose made insulating panels or blocks as the formwork for in-situ concrete. Once the concrete has been poured, the panels remain in place to act as thermal insulation.

There are a variety of different block and panel systems, using typically either expanded polystyrene insulation (EPS) or extruded polystyrene (XPS).


The design and thickness of the overall construction depends on the properties required for the wall and the structural requirements for the in-situ concrete wall, including steel reinforcement if necessary.

A variety of shapes and components exist permitting the construction of different building forms including curves. The exterior of the building can be clad in any finish and internally is either dry lined or plastered.


The inherent properties of the concrete mean that the systems perform well in terms of fire resistance/sound insulation/flood resilience/thermal performance and airtightness. System specific certification is provided. Fire retardant is applied to the insulation elements as part of the manufacturing process.


ICF systems are quick to assemble, require low labour input and a reduced need for skilled tradesmen. It can also be erected in wet and freezing conditions facilitating an early water tight building enclosure.

Just-in-time deliveries and direct placement of ready-mixed concrete reduces waste and site storage requirements.

Further information on ICF can be downloaded from Insulating Concrete Formwork, published by The Concrete Centre.

Insulating Concrete Formwork