Sustainability
“Sustainable development is… development that meets the needs of the present without compromising the ability of further generations to meet their own needs.”
– World Commission on Environment and Development, Our Common Future, 1987
ICF Construction easily meets this definition of sustainability and is more sustainable and environmentally friendly than standard masonry or timber frames when considering the lifetime of a building from construction to use in service, to its final demolition and disposal.
SO HOW IS ICF CONSTRUCTION SUSTAINABLE?
MINIMAL INITIAL IMPACT
AN A+ GREEN GUIDE TO SPECIFICATION RATING
The ICF Construction system has been awarded an A+ by the BER under its Green Guide to Specification assessment scheme.
An A+ demonstrates that the ICF Construction system is one of the most environmentally friendly and sustainable ways that you can build today.
EMBODIED ENERGY
Concrete, a major element of ICF Construction, hasn’t traditionally faired that well in ‘Eco’ terms because of the high amount of energy needed to produce cement but recent developments in concrete technology have changed this. A typical structural concrete mix using 50% ground granulated blast-furnace slag as a cement replacement now has embodied CO2 in the order of just 12% of what would have been the original 100% cement figure.
Similarly, expanded polystyrene (EPS), a natural by-product of the petroleum refining process and the other major element of ICF construction, when used for insulation purposes will recoup the CO2 generated during its production within the first week of the building’s operation, simply by reducing occupant heating/cooling demands. EPS is also HCFC and CFC free.
WASTE REDUCTION
Since the ICF Construction system has web placement at 150mm centres, many cut-off pieces can be re-used in the build. By using ICF Construction over competing products waste is dramatically reduced.
Especially when combined with the reversibility of the forms.
BUILDING OPERATIONAL SUSTAINABILITY
Typically 10% of CO2 emissions come from the construction of our built environment. But a massive 50% comes from actually using our buildings, 27% of which is residential use.
And this is where ICF Construction really comes into its own, both in terms of its durability and its energy efficiency, proving that it is a truly sustainable modern method of construction (MMC).
The following points are considered as key aspects to consider when developing sustainable construction:-
• Energy Saving
• Insulation
• Thermal Mass
• Air tightness
• Durability
• Fire resistance
• Sound Insulation
• Flood resistance
• Maintenance
• Security
The way in which polystyrene and concrete is combined in ICF Construction means this system provides outstanding performance levels for each of these key points.
ENERGY SAVINGS
INSULATION
ICF Construction provides a high level of standard thermal insulation with a U-Value of 0.215W/m²K. The insulation envelope of the building is absolutely complete when building with ICF Construction, in contrast to all other building system which require manual site intervention to install the thermal insulation after the structure is built. Additionally, there is no convection loss of heat within the wall as the insulation is in intimate contact with the structure.
THERMAL MASS
Concrete construction naturally has a high thermal mass, which is the ability of a material to store excess heat energy during the day. This heat energy is then released back into the building at night as it begins to cool. The strength of an ICF Construction allows for concrete elements to be used internally throughout, including all floors and internal walls, maximising the thermal mass available.
AIR-TIGHTNESS
Current Building Regulations set standards for the air tightness of structures, measured using an Air Permeability Rating. A number of 7 is the required minimum and 2 being required for passive homes.
Because this is a poured concrete method of construction the structure is effectively monolithic, thus air-leakage is reduced to an absolute minimum. ICF Construction is extremely airtight, with a typical structure achieving an air permeability rating of 2 or less.
These factors combine to produce an extraordinary thermal performance in the finished house. There are numerous testimonials from residents of homes built using ICF Construction reporting annual heating costs of the order of €100 per thousand ft² of floor area and less, using a variety of heating systems. A house built with ICF Construction will easily meet the building regulation’s requirements for air-tightness, junction thermal bridging minimisation and U-Value needed for an A3 rated home, as standard.
DURABILITY
An ICF Construction structure is built to last. Concrete is inherently durable, and when cast within the ICF Construction system, it cures without suffering exposure to extreme temperature variances. This results in a far higher strength of set initially, but the insulation provided by the polystyrene also permanently reduces the stress on the concrete caused by thermal expansion and contraction, enhancing its lifetime well beyond standard masonry construction.
FIRE RESISTANCE
Concrete construction is extremely resilient to fire damage. ICF Construction walls have fire-performance ratings of up to 3 hours. In addition the EPS used in the manufacture of ICF Construction is flame retardant and both the internal and external finishing systems are certified Class A, inflammable. This means that an ICF Construction is extremely safe and resilient in the event of a fire.
SOUND INSULATION
The mass of the concrete within the ICF Construction system makes for amazing sound absorption with typical sound reduction of 52 dB across the finished wall.
FLOOD RESISTANCE
Neither concrete nor expanded polystyrene rot or suffer from water damage, making ICF construction extremely resilient to flood damage. The monolithic structure is also much better at resisting water ingress.
MAINTENANCE
The physical and chemical constancy of both concrete and EPS in an ICF building means there is practically no maintenance required to the structure at all.
SECURITY
The inherent strength of the solid concrete core makes an ICF Construction structure safe and secure.
AFTER USE DISPOSAL
RECYCLABILITY
Even though an ICF Construction structure has a very long lifespan, at the end of the building’s lifetime, both the polystyrene and the concrete can be fully recycled, along with the plastic bridges which are already made from 100% recycled plastic.