Bricks are one of the most traditional materials available in construction, although many companies prefer to go for concrete and modern options in larger builds. Brick walls are strong and effective, but how well do they hold up to a fire? Are bricks fireproof and, if so, what sort of bricks should we use to fireproof our properties more effectively?
Most bricks are fireproof because their method of construction and properties allow them to withstand heat and flames. However, it is important to remember that brick-built homes have more than just bricks in the walls. Also, there is a big difference between regular bricks, mud bricks, and firebricks.
So, let’s look at these simple building blocks a little more closely. Why are regular construction bricks so great for fireproofing a home, and what else should we consider when using them?
How do firebricks and mud bricks differ from these regular bricks, and when should we use those? Also, are there any better fireproof building materials in the current climate?
Table of Contents
Fire Resistance of Traditional Bricks
We’re going to start with the most common form of a brick. These are the porous kiln-fired blocks we use to build homes and walls.
Brick-built homes aren’t always the go-to approach these days because there are other options available.
But, brick building blocks do allow for a strong exterior wall, and they can look nice depending on the finish.
A key reason that bricks are fireproof is that they are forged in fire. These blocks dry out into tough bricks under high heat in a fire kiln.
Traditional bricks comprise of clay and water mixed together, added to a mold, and fired. Production lines can now create large numbers of these in factories where each brick has the same properties and shape.
This allows for a more stable and uniform shape of a wall. Originally, they would have been hand-molded – although this practice still occurs today during some artisan builds.
A well-constructed brick wall can offer great fire protection. At their best, a brick wall can withstand a heat of 1200 degrees celsius or 2192 degrees Fahrenheit and offer four-hour fire protection in a blaze. At their worst, this may only be an hour.
But, the rates will vary depending on the quality and the bricks used. The thicker they are, the better the protection.
Brick Buildings Require Mortar.
One thing to be aware of when considering the fireproof properties of brick buildings is the mortar between the bricks.
Mortar is essential for bonding the bricks together for stability. This isn’t like a dry stone wall or a LEGO house where everything clicks together.
Speaking of, building bricks may be fireproof, but those LEGO bricks are going to melt in a blaze and give off some toxic fumes.
Mortar is an issue because there are going to be some combustible materials in there. These can catch alight, and the trail of mortar could create a path for the blaze.
The fireproof bricks would slow the process, but they wouldn’t be 100% fireproof. On top of that, you don’t know what the ratio of materials and composition of the mortar is.
What Are Firebricks?
Firebricks are different from those used in general construction. These are again forged by fire and used for building secure structures.
But, they are typically used in places where there will be high heat and fires, such as fireplaces, furnaces, and ovens. These bricks are a lot less porous than the standard bricks and have a higher heat tolerance.
This makes it incredibly unlikely that they will catch fire or contribute to the spread of fire. Instead, you get a nice secure barrier between the flames and the rest of the structure.
Another important difference is that these bricks have a much higher heat resistance of up to 1350 degrees Celsius or around 2460 degrees Fahrenheit.
This makes them perfect in these high-temperature environments.
But, they still have their limitations in construction more generally. Each brick has its role, which leads us to an alternative option.
The Potential Of Mud Bricks In Fireproof Construction.
Traditional clay bricks certainly have their benefits for fire protection in building work. But, there is another option available gaining popularity.
Mud-made bricks are, as the name suggests, blocks formed out of mud rather than clay and water.
You get a different look and consistency to these bricks, and some people dislike them because of their poor insulation.
But, they are a great natural and sustainable option that can withstand high heat.
Why Aren’t Bricks More Common In Construction If They Are Fireproof?
You don’t see so many brick buildings with traditional or mud bricks for a few reasons.
Mud bricks are still quite a modern trend, so it will take time for this to catch on in the right communities. Traditional bricks aren’t ideal because of their low insulation properties.
Other materials are easier to use and more efficient. Some also have a strong fireproof rating.
Many companies now use concrete because it is heat-resistant, and it is non-combustible. It is easy and cheap to use and will quickly slow the rate of a fire.
Therefore, it is perfect for larger buildings and complexes. You can also find cement used as a render for other materials like bricks and similar building blocks.
Then there is Gypsum, also known as drywall. This is another great option with low flammability because of its composition.
The combination of glass fibers and water makes it difficult for fire to pass through. Eventually, all that water will turn to steam and evaporate away.
Still, it takes a while.
The Best Materials For Fireproof Construction.
The debate over the best construction materials for fireproof homes has evolved in recent years due to the current climate.
Wildfires aren’t freak incidents anymore.
There was a time when one or two might sweep in and threaten communities, but now it is an inevitability for a lot of areas in Southern California.
The biggest fear is that wildfire controls won’t be enough to extinguish the spread and that the blaze will destroy properties and livelihoods.
We saw it happen in Paradise, and it will happen again as summers get hotter and drier.
This is where the arguments for and against brick-based constructions become more significant. There are still far too many homes using timber and other materials that can burn with ease.
Even the best fire retardant sprays aren’t going to hold back a wildfire from engulfing those structures forever.
Brick buildings could be a good solution, as long as they are still affordable to make and offer enough insulation and green credentials.
Those mud bricks are a great choice for greener fire-proof building materials in California because they are so easy to make out of local materials.
They could prove to be a more protective barrier against fires, protecting homes from the next wildfire that comes a little too close.
However, there are also calls for alternative options like straw-bale bricks.
Either way, house fires can be devastating. Check out this article I wrote about the 9 most common causes of house fires and how to prevent them.
What Are Straw Bale Bricks? Are they fireproof?
We are stretching the definition of brick a little here as these aren’t the same strong blocks of clay, mud, or other earthen material.
But, they are similar in shape and stackable for the same sort of effect. There are pros and cons to this material over bricks, but one pro is the surprising fireproof rating.
You might wonder how a straw bale can be fire-resistant when straw easily catches alight in those hot dry summers.
However, these compressed bale blocks don’t allow for any oxygen, starving a possible fire of fuel and making it harder for the bales to burn.
They will burn eventually under extreme conditions.
Still, tests show that they can last for four hours. This is a long time during a wildfire and allows for much more time for fire services to put out a blaze before it gets through that barrier.
You might lose your garden, but you have a reduced risk of losing your home.
Additional benefits here are the strength of the walls with the metal pins and cement renders, as well as the use of local waste materials and labor to create the blocks.
It is a strange concept but one with potential.
Bricks As An Alternative Fireproof Material.
To summarize, bricks are a great option if you need a fireproof building material. The traditional models from clay are highly heat tolerant and can last for hours in a blaze when used correctly.
Their firebrick cousins offer great fireproofing due to their density and heat resistance and are ideal for heat-proof areas like furnaces and ovens.
However, with the world the way it is, we can’t overlook mud bricks and straw bricks for their benefits as sustainable materials in areas prone to wildfires.
Basically, we don’t have to rely on treated timber in areas prone to fires, and there are more attractive options than concrete.