Net zero energy buildings are becoming more common as more emphasis is being placed on energy efficiency and energy savings. ICFs are the perfect material to use for achieving net zero energy standards.  

What is a net zero building? 

A net zero building is defined as a structure that can generate more energy than it consumes.  This can be accomplished through a variety of strategies, but the core principle requires that a building be energy efficient and leverage renewable energy generation to offset its energy demand.

In a typical residential home, about 40% of the overall energy consumption in a home is consumed by heating and cooling applications.  Heating versus cooling loads can vary drastically by climate zone, but often one load will offset the other resulting in 40% overall usage for the home. 

One of the best ways to influence a building’s energy use for heating and cooling is to ensure that the structure is well insulated and resistant to outside temperature influx along with air leakage.  Continuous insulation provides some of the best thermal resistance against temperature change from heating or cooling loads imposed by the outside environment.  Making sure that the house is well sealed will also ensure that heating or cooling placed into the home will stay and not equalize with exterior temperatures.  The more energy loss a home experiences through energy transfer and leakage from the outside, the more energy will be consumed to keep the home at a desired temperature. 

BuildBlock Insulating Concrete Forms (ICF) provide solutions for each instance.  An ICF wall is composed of two layers of continuous insulation on both the inside and outside of a concrete wall.  This continuous EPS insulation, along with the thermal mass of the concrete, provides an extremely insulated and airtight wall.  The mass of the concrete provides an additional barrier against large exterior temperature swings because the concrete produces a thermal lag effect slowing energy transfer through the wall.  This means that when it gets very hot, or very cold outside, an ICF wall takes a very long time to change temperature slowing energy loss through the walls.  This massing concept has been well demonstrated in forms of architecture such as adobe in the southwest.  Since the insulation and concrete are also continuous and monolithic, air infiltration through the wall is very low.  Each of these attributes contributes to a wall that significantly outperforms traditional cavity frame construction techniques.  Results can vary, but research shows that structures built with ICF can reduce heating and cooling energy use in the range of 30-60%.

Reducing energy use in a building is one crucial step to accomplish a net zero build.  By leveraging the insulation and thermal massing of ICF’s the overall energy use of the home can be significantly reduced.  Once the building envelope is as efficient as it can be, other strategies can be deployed to reduce energy use, such as energy efficient appliances and lighting.  Finally onsite generation of power can be designed to accommodate peak energy demand, resulting in a home that can function as net zero.