Whether they think of it as “building green” or “sustainability,” today’s consumers expect homes and other low-rise structures to have minimal environmental impact, yet meet or exceed their lifestyle needs. They want properties offering comfort and security with low energy bills and low maintenance. They also demand healthy interiors that promote well being. And they want all of this in an attractive package.

Contemporary concrete building systems offer features that purchasers and builders value; strong and solid construction that provides comfortable shelter from typical weather, and minimizes property damage while protecting occupants from extreme weather, like natural disasters. Yet strength and durability alone are not enough: the systems have to be easy to design and build and be versatile to suit any architectural style. Concrete systems are that and more.

They form tight building envelopes that minimize air infiltration, simplify the addition of insulation, and provide thermal mass for more consistent temperatures and decreased energy usage. This is beneficial from an environmental standpoint, and can contribute toward a building’s greenness in many rating systems and some codes.

Even though many concrete building systems have been around for a long time, consumers (and some builders) may not be aware of them. Or they may have only a limited understanding of them. PCA began a targeted promotion of concrete systems for residential applications in the mid-1990s, intended to introduce a new audience of buyers and builders to the wide variety of structural concrete products suitable for building homes. Systems included concrete masonry (“block”) and poured in place concrete (removable forms), precast and tilt-up, shotcrete, insulated concrete forms (ICFs) and autoclaved aerated concrete (AAC) which is a lightweight concrete formed as blocks or panels. Construction of above grade walls for concrete homes increased from about 3% at that time to nearly 11.1% in 2008, or about one out of every 9 homes built.

Residential Market Share of Above Grade Concrete Walls
Sources: NAHB Research Center, ICFA, and PCA Market Research Surveys

PCA now promotes concrete systems for residential and other low-rise structures. Most if not all of the benefits of concrete construction are suitable to both classes of buildings. The links below provide detailed descriptions of each wall system and important characteristics of them.

There's more than one way to build your home with concrete:
	Concrete Masonry Units Traditional concrete masonry units, referred to as “CMU” and sometimes “block,” have a long history of use for basements and above grade walls of homes. Whether the choice is plain units finished with other materials or architectural units that remain exposed to view, concrete masonry walls are installed by skilled masons, and can be insulated, reinforced, and grouted to form energy efficient, strong building envelopes.
	Insulating Concrete Forms (ICF) As lightweight modular panels or blocks, ICFs combine easy form placement with a finished concrete wall encased between two layers of insulation. These systems have established themselves as environmentally friendly solutions to comfortable, durable buildings for housing and many other applications for low-rise construction.
	Removable Forms (Cast-in-Place) Casting concrete in place involves the use of removable, or temporary, forms, typically made of aluminum. Some forming systems are adapted from other categories of construction, like tunnel building, to speed the process. Rigid foam insulation is often placed between forms and fastened with a system of non-conductive ties before concreting begins. The result is a solid wall with thermal mass and good insulating abilities.
	Panel Systems: Precast and Tilt-Up There are two main types of panel systems used for concrete walls: precast concrete and tilt-up concrete. Both types of panels are typically erected with a crane, but differ in where they are cast. Precast concrete panels are built in a controlled manufacturing facility and shipped to the site on trucks. Tilt-up panels are site cast from ready mix concrete, usually formed on top of the floor slab, for minimal site disruption. Flat casting simplifies the concreting process and panelization offers an opportunity for repetition and walls that go up fast.
	Autoclaved Aerated Concrete (AAC) Autoclaved aerated concrete, or AAC, is made with fine aggregates, cement, and an expansion agent that causes the fresh mixture to rise like bread dough. In fact, this type of concrete contains 80% air. In the factory where it is made, the material is molded and cut into precisely dimensioned units.
	Shotcrete Shotcrete is a process where concrete is projected or "shot" under pressure using a feeder or "gun" onto a surface to form structural shapes including walls, floors, and roofs.

 
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