The fire-resistant properties of concrete are fairly easy to understand. The components of concrete – cement (limestone, clay and gypsum) and aggregate materials – are chemically inert and therefore virtually non-combustible.

Is concrete resistant to fire?

All concrete and masonry products have to be tested before they can be declared fireproof or fire resistant. Over decades, these tests have proven that concrete is the most fire-resistant building material. Because the ingredients in concrete are chemically inert, they are nearly incombustible.

Is normal cement fireproof?

Most mortar is fire resistant to some extent, as the materials that make it (usually a mix of clay, cement, lime, and sand) are resistant to fire and heat. However, a drastic increase in temperature can cause mortar to crack and expand.