How insulated concrete form works

If you're building a new home to environmentally conscious standards, consider using insulated concrete.

Insulated concrete forms (ICF) are hollow blocks or cast panels of concrete that many builders use for creating a home or building that is energy-efficient, soundproof and comfortable. The forms combine an excellent insulating material—expanded polystyrene—with one of the toughest building materials around, steel-reinforced concrete. Insulated concrete blocks are quickly becoming a go-to material for both residential and commercial construction.

Creating insulated concrete

Insulated concrete forms were first created just after World War II, as an inexpensive and versatile building material. The simplest explanation of the forms is that they look and connect to one another—a little bit like Lego bricks. They are very durable, with a range of benefits for home and building owners.

The blocks are made out of three different materials, which are combined on site. They start with the interlocking foam blocks or forms, which are held together with recycled polypropylene webs. The foam forms are available in a range of different shapes and options, including structural panels, flat walls, grids and post and lintel systems.

Then, the different shapes are laid out and stacked to the height of the walls being built. These are filled first with steel rebar for strength. The webs inside the forms help to hold the rebar in place after it’s inserted, to help keep it in the right area. Next, the forms are filled with concrete on the interior, surrounding the rebar and creating a structurally sound building. The exterior cladding material of your choice is installed on top of the foam on the outside of the wall.

On the interior of the home, the plumbing and electrical wires are run right through the foam itself after the concrete has been poured. The drywall or plaster is put over the foam, and the interior walls are finished like in any other home or building. From an aesthetic standpoint, the structure will look exactly like any other; there are no visual differences between a home or building built with insulated concrete forms and one built using more traditional stick building methods.

Advantages of insulated concrete forms

The benefits in performance and comfort from using concrete forms are many. ICF homes are very energy-efficient, because they create a tighter building envelope. In fact, it’s common to see a reduction in energy expenditure of between 25 and 50 percent, which benefits both the environment and your wallet. ICF buildings are also sustainable, using roughly 10 fewer trees than traditional buildings.

ICF homes and buildings are also comfortable to inhabit. Studies have found that they cut air infiltration, which brings in outdoor allergens and irritants, by up to 75 percent, compared to a typical house frame. They also help to reduce sound from the outdoors, so your home is quieter. This type of insulation has also been found to inhibit mold growth by helping to control the humidity levels inside the building, leading to better indoor air quality and more consistent temperatures.

Also, ICF buildings are resistant to damage from hurricanes, tornados and earthquakes. They require no additional retrofitting or reinforcement to help protect them from these natural disasters, which is particularly beneficial for new homes in areas prone to such occurrences. The insulated concrete is also fire-resistant up to four hours, which can provide significant protection for the home interior as well.

Finally, you can use insulated concrete forms to build any style of architecture. The finished structure can be clad in any material as well, including wood, brick, stone, stucco, fiber cement and vinyl. This means you can achieve any design, floor plan, layout or unique building shape, while reaping the other benefits.

Build a better building

ICF technologies have been rapidly gaining in popularity as more people are interested in building homes that are durable, energy-efficient and comfortable—and with more stringent building laws being enacted in areas prone to natural disasters, ICF buildings provide a solution to several different building issues at once. Consider using ICF for your next building project to reap the many benefits that this technology can bring.