ICF (Insulated Concrete Forms) is a way of building that is more and more popular due to its enhanced energy efficiency and durability. This method of integrating insulation and structure has been increasingly popular for foundations but there are now versions available with which the walls too can be built using the same technology and this article is intended to give you the ABCs of ICF to help you increase your understanding and hopefully answer some of the questions you might have.
Along with the inherent energy savings, a home built with ICF walls has increased wind resistance and up to three times the sound proofing from exterior noises that traditional wood construction can offer. These advantages may help justify the increased building costs of approximately 2% to 5% over traditional methods.
It starts with a hollow, polystyrene bloc within which a plastic web and rebar, preferably epoxy coated for rust resistance, are installed in the center. These blocks are assembled on site to make the outline of the floor plan and resemble a giant set of Lego blocks once put together.
Most insulated concrete forms use non-toxic expanded polystyrene for which there is no danger of out gassing within your home. The air and water tight seal can even help to create a healthier environment as it prevents mould caused by water infiltration and keeps outdoor allergens from entereing.
After the blocks are assembled, the concrete is poured into the empty space creating a solid envelope for the building. The electrician and the plumber use a hot knife to cut the channels directly in the polystyrene.
Some insulated concrete forms can accomplish the work of several layers of structural materials which permits installation of the gyproc on the inside and the siding on the outside directly on the insulated form.
Floors and ceilings are usually made of wood but there are manufacturers who offer products made of the same material as the insulation of their ICFs.
What is important to remember is that not all ICFs are the same and the manufacturers of these products train contractors, either at their plant or by offering on site supervision for the first build. The best way to find a qualified contractor is through the manufacturer of the product that interests you.
Many municipalities have adapted their codes for this kind of construction but if this isn’t the case, some manufacturers will offer technical support to work with your particular municipality in order to help them to develop the codes required.
At Drummond House Plans, we can modify the plan of your choice for ICF, either at the foundation level or for whole wall construction and our design team can even help you with this option for your renovation project.