Insulating Concrete Formwork (ICF)

Next generation insulating concrete system


Faster Build, Energy Cost Saving & Super Low U-Values

Thermoform Insulated Concrete Forms (ICF)

This all-in-one construction system combines the excellent insulation capacity of Neopor® polystyrene supplied by UNiBLOCK Ltd & the structural resistance of concrete. This next-generation solution from CEMEX is unrivalled on the market. It consists of large dimension blocks made up of:

  • two graphite polystyrene panels
  • integrated steelwork
  • internally cast concrete.

Through the combination of these materials, Thermoform® makes it possible to produce robust solid-wall structures, fully insulated, with superior airtightness. The performance far exceeds requirements under current UK building regulations & also meets the requirements for passive buildings. Thermoform® helps achieve a high level of interior comfort, as well as better cost control in terms of heating & cooling the building.

Accelerate Your Builds!

Using Thermoform® takes weeks off any build program, as the walls are all designed and pre-fabricated offsite and sent ready to be assembled with an easy to follow plan, giving you the speed of offsite construction with the flexibility of more traditional systems. Walls can be assembled to suit the program and there is no expensive machinery or special skilled trades needed to construct. Full training and system orientation is provided along with the chance to become a certified CEMEX Xpert® in our Building Solutions (to be launched in 2019)


Global pressures on energy supply along with a greater emphasis on the environment and sustainability have driven innovation in the manufacture and delivery of many common everyday products. Keeping up with modern methods of construction has been a challenge for the industry, where time and cost have such a big impact on business.

Offsite Pre-Fabrication

Thermoform® can be adapted to any existing house or building design or incorporated into new types as required. Plans sent to CEMEX are estimated and designed by our team, and each house type and individual wall is modelled and planned for the most efficient use of materials using our bespoke design software system.


This then generates drawings for each wall, which once signed off by the contractor can be put straight into production for pre-fabrication at UNiBLOCK's offsite facility. Each wall is then fabricated to suit, labelled and sent to site along with installation drawings for the site teams. Once on site, the system can be built and concreted at the rate of around 8m²/per operative/per hour.


Another key component of the Thermoform® system is the integration of the CAVALOK cavity closer system for doors and windows. Designed and fabricated by our partners at Subframes UK, the CAVALOK system works perfectly as a standard detail for thermally broken subframes within the walls, and is a familiar practice to most traditional builders. Again, for ease of use on site, each opening comes to site labelled and ready for direct insertion into the wall.

What are Insulated Concrete Forms?

CEMEX Thermoform® is an Insulating Concrete Formwork (ICF) system designed to take construction into the modern age. The system is a combination of large, lightweight panels which lock together to provide a permanent formwork into which CEMEX Readymix Concrete can be poured.


Once the concrete is poured the system becomes a high-strength structure, with the added benefit of the formwork remaining as a thermal insulation barrier, providing typical U-values of 0.16 W/m2k.


The Thermoform® system has a range of core thicknesses to suit a wide variety of end-uses and combined with the flexibility of working with in-situ concrete this allows for greater creativity in the design of the building, making architectural dreams more achievable. This flexibility also allows greater choice in other materials used such as floors, roof systems, cladding and windows, enabling better specification and use of sustainable materials.


The use of Thermoform® is not just limited to housing. With its structural design and offsite prefabrication it is also ideal for:


  • Apartments
  • Commercial office blocks
  • Care Homes
  • Hotels
  • Student Accommodation


The process of building with Thermoform® is quick and straightforward, with significantly lower labour costs and reduced reliance on specialist equipment in comparison to traditional techniques. Add this to the energy efficiency of the finished building and the whole-life cost benefits of using Insulating Concrete Forms become clear.


See our Frequently Asked Questions here


ICF Features

  • High thermal resistance - A wall made from Thermoform® makes it possible to attain thermal resistance (U) values as low as 0.16 w/m²K 
  • Eliminates thermal bridges - With its double internal and external insulation, Thermoform® eliminates all thermal bridges, sources of draughts and heat loss and avoids the use of additional thermal bridge breaks. 
  • Excellent airtightness - The monolithic concrete structure and subframe connecting the structure and joinery enable unparalleled airtightness (typically 0.7ac/h n50), at a level well below that set out in Part L of the UK Building regulations


ICF Benefits

  • Fast & simple to construct
  • Cost effective solution
  • Low, zero or passive energy performance
  • Sustainable and recyclable materials
  • No ongoing maintenance required

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