Some Useful Building Materials With Strong Fire Resistance Strength

Our dwelling house should be adequately strong to withstand earthquakes, floods as well as outbreak of fires. But it is a major concern that not every house is properly fire-resistant.

But if any house is built-up in a perfect manner with fire-retarding materials, the fire can be resisted for a longer duration and thus the risk is minimized significantly.

Properties Of Fire Retarding Materials:

1. It never be affected with fire easily and also transmits heat gradually.
2. It does not break up under the impact of heat caused by fire.
3. It does not spread out under heat and consequently does not provide extra stresses in the building.
4. It does not lose its strength if affected with fire.

Given below, the details about fire resisting characteristics of some building materials which are mostly utilized in house construction.

Concrete: Concrete has strong fire resistance strength. The behavior of concrete mainly influenced by the quality of cement and aggregates available within it.

For reinforced concrete and pre-stressed concrete, the placement of steel reinforcement is also very crucial. Larger concrete cover over a member leads to superior fire resistance to it.

Usually, the strength of concrete is lost beyond the temperatures of 250oC. The reinforced concrete can undergo the temperatures of up to 1000oC for about an hour.

Steel: Steel is also considered as a good conductor of heat. It yields at 600oC and dissolves at 1400oC. The tensile strength is reduced under the effect of heat resulting from fire. Steel columns are in danger during fires. Steel reinforcement can make the reinforced concrete structures weak.

Also Read: How to measure various building materials with formulas

So, the brick work or thin concrete cover should be provided with steel columns to safeguard them. Steel grills and beams should also be coated with fire resistant paints.

Glass: Glass is considered as a poor conductor of heat. It enlarges slightly upon heating. When the glass is cooled down, after being heated, cracks are developed.

Tempered glass is heat treated and it offers about four times more strength as compared to regular glass. Glass is normally reinforced with steel wires to enhance the fire resistance strength. Even if the glass cracks or breaks, the broken pieces are still in their original positions.

Aluminium: Similar to steel, aluminium is also a good conductor of heat. But it offers greater fire resistance than steel.

Bricks: Bricks are also considered as poor conductors of heat. They can withstand temperatures of up to 1200oC. When the quality mortar is good during construction, bricks offers superior fire resistance. Brick walls can easily defy fires up to 1 to 4 hours.

Stucco: Stucco is a specific type of plaster that is constructed with plaster, sand and lime and applied as a very strong and long-lasting fire resistant finish material for buildings. It is provided in 2 to 3 coats. A one inch thick layer of stucco can easily give a one hour fire rating to a wall.

Timber: Timber catches fire quickly and it should be coated with fire resistant like ammonium phosphate, ammonium sulphate, borax, etc. Sometimes fire resistant paints are also used on timber as a coating to get rid of catching fire fast.

Gypsum: The different types of structural materials contain underlying gypsum sheathing for superior fire-resistance. The gypsum board is frequently used for interior finish. Gypsum board or drywall comprises of a layer of gypsum squeezed among two sheets of paper. Type X gypsum board is specially provided with several additives for greater resistance to fire.

The paper on the exterior layer of the gypsum board burns gradually to stop the fire from further spreading. Next, the non-combustible core with gypsum (water, chemically combined with calcium sulphate) is impacted. Because of fire, the water emerges as steam, impeding the heat transmission through the gypsum board. Finally, the gypsum core withstands fire infiltration for a specific time period.

Asbestos: It stands for a non-combustible material. It has strong resistance capacity against fire but also leads to waterproofing of buildings. If the asbestos are added to mortar mix, the tensile strength is raised significantly. Due to its fire resistant properties, it is frequently used in building up the asbestos bricks which are again utilized to build fireplaces and brick ovens.