Insulating Concrete Formwork “building shell” systems
Insulating concrete formwork (ICF), also known as permanently insulated formwork (PIF), is the family name for highly insulated concrete walling systems which are growing rapidly in popularity as the Government push toward ‘carbon neutral’ homes gathers pace driven by The Code for Sustainable Homes.
ICF systems are however equally suitable for any building type as demonstrated in North America and Canada and are also widely used for basements in both domestic and commercial buildings.
The walls consist of large, hollow, lightweight polystyrene block or panel components which lock together without any intermediate bedding materials to provide the formwork into which ready-mixed concrete is poured. The formwork stays in place to give the wall its required thermal insulation which can reach down to levels as low as 0.1 W/m2degk.
The wall construction is extremely airtight and the building shell can easily meet the Canadian ‘Super E’ requirement or the German ‘Passiv-haus’ standard for a building with no separate heat source needed.
We are working with a number of ICF companies to offer a housing “building shell” system to builders and self-builders alike. With the simple addition of an air-source heat pump, the shell can easily reach level 4 of the Code for Sustainable Homes at an affordable cost so the social housing sector can at last have houses to high code levels which are truly affordable, both to run and build.
Ready-mixed concrete options
At Aggregate Industries we have developed a number of sustainable ready-mixed concrete mixes for ICF applications which can be delivered through our ready-mixed concrete businesses Bardon Concrete and London Concrete. The ICF- Crete mixes are available in a variety of strengths and densities with the inclusion of cement replacements and can include recycled and secondary aggregates.
We were the first construction materials company worldwide to be certificated under the BRE (Building Research Establishment) Global BES6001 Framework for Responsible Sourcing for the production of its construction materials. This certification gives credits towards all BREEAM schemes including the Code for Sustainable Homes.
All ready-mixed concrete from Bardon Concrete and London Concrete is manufactured under the QSRMC quality assurance scheme and complies with EN206 BS8500. ICF- Crete has been specifically designed to fall in line with the demands of all BREEAM (Building Research Establishments Environmental Assessment Method) schemes including the Code for Sustainable Homes. Each mix design is made to fulfill the specification of the client, whether it contains a required percentage of replacement materials or an elemental BRE Green Guide rating.
View ICF-Crete technical information
Flooring options for ICF systems
Aggregate Industries also produces various flooring types to suit ICF systems.
Concrete options for ground floors include:
- Ready-mixed concrete slab
- Raft foundations
- Piled foundations and ground beams
Concrete options for upper floors include:
- Precast beam and block floors
- Precast beam and ready-mixed concrete cast on polystyrene formwork
- Precast hollowcore slabs
- Precast solid slabs
Our structural precast concrete company Charcon Precast Solutions can offers its flooring and stairwell products manufactured from Emerald® mixes to help maximise the points available from concrete in the Code for Sustainable Homes and other BREEAM schemes. In addition, it is proposed to recognise thermal mass in SAP 2010 and, if the precast concrete floor can be left exposed from the underside, this will boost the thermal mass performance of the whole ICF system.
Photographs courtesy ICF-tech