Insulated Concrete Forms or ICF is proving to be a revolutionizing technology in the construction industry. An alternative to cement, ICF are modular units that can be set in interlocking panels and blocks to complete the construction. Think of interlocking blocks of bricks without the need for cement to hold them together. The panels are made from polyurethane and polystyrene material and filled with concrete.
ICF blocks were initially conceptualized in Europe but the technique had evolved long before in the 1960s wherein experimental builders were using modern foam plastics. In the past decades, several thousands of homes and offices have come up across Europe, Australia and North America that use ICF as the structural building blocks.
ICF perfectly suits constructions and building deigns with strong structural integrity and simple lines. ICF walls have a predictably higher performance in the degree of structural support and thermal mass. Easily stacked, ICF blocks also offer higher degree of insulation. This makes it perfectly suitable for several commercial and specialty building construction, ranging from temperature controlled warehouses to laboratories.
The design supported by ICF
Passive houses, as they have come to be called, use ICF building blocks to reach ultra-low energy usage and with nearly zero emissions. The main aim of ICF is to create a tightly sealed, economical, and aesthetic and highly insulated envelope that can help achieve a higher degree of control over airflow. This helps create a continuously comforting environment for all occupants and more importantly, more sustainably, without too much dependence on HVAC. Most commonly used heat recovery is dove through mechanical heat ventilation.
Features of ICF Buildings
Appearance of Insulated Concrete Forms
The ICF look like normal brick blocks but with an interlocking panel design that can snugly fit into each other. The appearance of ready-to-use ICF structures are however determined by the facing materials used to cover the surface of the foam/plastic framework.
How good is the structural capability?
The typical ICF block consists of fire resistant polystyrene plastic blocks with interlocking and self supportive design. This acts as the traditional formwork of poured concrete. With some ICF, the interlocking is as simple as blocks on the corner and there are other multi-purpose corner blocks. The self supporting blocks lock tightly to create a strong enough structure that can hold poured concrete. Once the concrete sets, they add the load bearing capacity to the system. Some builders use additional reinforcements within the framework as is needed. Some systems also use reinforcements laid on the connectors that connect the inner and outer skins of the ICF.
A typical ICF variant also comes as foam panels that are sized and shaped to suit the standard window head or floor heights. These can be further joined with a series of connectors.
ICF panels don’t just suit wall construction but are also being used as floor material. In fact ICF flooring is reported to weigh 40% lesser that the traditional concrete flooring. The blocks, herein, can be laid for independent decking and more importantly, form a continuous reinforced structure that is connected to the walls. The same approach has also been used in many buildings to create roof decks. With ICF walls, timber flooring is also a great option to go for. ICF buildings are 8.5 times stronger than similar wooden framed buildings.
Thermal mass and insulation
Thermal mass of ICF homes are contained through insulation. The result is a continuous and consistent core temperature. The level of insulation that you can hope to achieve however depends on the kind of ICF units used and their thickness. One of such German made ICF that is widely popular in North American homes has insulation rating between R6 and R15.
Rigid foam supported by mass concrete offers an airtight construction that also makes ICF homes noise insulated too. A typical 300 mm wall will deliver a sound transition of 48. In simple terms, you have your complete privacy even if you have a guest in the next room.
Another incredible advantage of ICF homes in fire insulation. Polyurethane and polystyrene don’t burn or support burning. However, they are liable to melt and release toxic gases. High quality ICF panels are however supported by a thick layer of plaster board that protects the foam from getting into contact with heat immediately. It is also usual for builders working with ICF panels to add flame retardants to the concrete, making the system self-extinguishing. The concrete is anyhow non-combustible. Overall, ICF homes are fire resistant to a higher extent and give you a longer time period for escape or disaster recovery.
The foam insulation doesn’t support dampness (with additional waterproofing) and consequently offers nothing of value to insects or rodents. Further, the panels are tightly packed and will not harbor pasts in your home. Manufacturers also use pesticides to add to the advantage.
The environmental impacts
ICF use concrete at the core of its construction which has been one of the major contributors to the climate change. Further, ICF use plastic derived from oil and steel. However, these are also the materials that have traditionally been used in building constructions. ICF however eliminates the use of cement, another major contributor to environmental pollution. Consequently, ICF can be said to be a more responsible way of using the limited resources and raw materials.
ICF homes also offer the advantage of insulation and energy saving. A lesser use of HVAC in the long term also reduces your carbon footprint, making it a more environment friendly alternative. Lastly, ICF homes are highly durable and this means minimal need for reconstructions or repairs.
Applications of ICF
ICF is gaining a lot of popularity in the hospitality industry. They are the perfect solution to lower energy cost and noise insulation between rooms. Some of the prominent chains include the Hilton and Marriot chain of hotels. ICF has also found its way into several laboratories and hospitals across Europe and North America. In Delaware, USA, Excel ICF Homes have been changing the way of home construction for the good.
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