Experience the true power of fire-resistant concrete

There is a hierarchy among architectural materials. Wood and granite are the most popular, glass and aluminium are the trendiest, and marble is the highest high-end. And then there's concrete...poor, unlovable concrete. We walk on it, drive on it, and even spit gum on it. Some respect. It's just so hard to love a material that's given us block housing, parking decks and most of the world's prisons. But things may be changing for the ugly duckling of architecture. There is a new trend toward embracing concrete for home construction, mainly because it's one of the most robust and most durable building materials (it can withstand earthquakes). It's also incredibly resistant to fire (which makes it safe for homes), thanks to its chemical makeup: cement (limestone, clay and gypsum) and aggregate materials are chemically inert and therefore virtually non-combustible.

The properties of concrete make it resistant to flames, and fire resistance is a key part of building codes. Determining a building material's fire resistance takes into account the rate of heat transfer and combustibility of that material under variable conditions such as the temperature of the fire, ventilation, and fuel sources within the building [source: Portland Cement Association]. While concrete walls can generally withstand up to four hours of extreme fire pressure, most wood-framed walls would fall in less than an hour [source: International Association of Certified Home Inspectors]. It's also important to note that when the concrete does burn, it doesn't emit toxic fumes, produce smoke or drip molten particles.

Concrete walls in a home act as a fire shield, protecting adjacent rooms from flames and maintaining their structural integrity despite exposure to intense heat.

 The fire performance of a material can be critical in residential construction, as it determines how well the structural integrity of the home will be maintained when exposed to intense heat and flames. In the next section, we consider a few examples, including a comparison of concrete and wood.

How does concrete protect your building?

Concrete is generally considered to be a good value in the home building when it comes to fire performance, as it holds up much better than wood in intense heat [source: The Concrete Center]. This is partly because concrete allows for compartmentalization (i.e. containment) of fire. For an example of compartmentalization, let's take a look at the burning of the World Trade Center (WTC) Towers on Sept. 11, 2001.

The intense heat of the burning jet fuel, which reached a temperature of 800 degrees Fahrenheit (427 degrees Celsius), was channelled by the 4-inch (10-centimetre) concrete slabs between each floor. These slabs limited the spread of fire, at least for a while. However, the tower walls were framed in steel and other materials, not concrete. As the heat of the fire topped 800 degrees Fahrenheit (427 degrees Celsius), the supporting steel structures weakened and began to collapse [source: Scientific American]. Still, most engineers agree that the fire performance of the WTC buildings on Sept. 11th was impressive, mainly because the compartmentalization of heat and flames gave thousands of people a chance to escape before the buildings fell.