Wood is one of the most ubiquitous materials for various applications, including flooring, furniture, doors, cabinets, etc. And it’s no wonder it’s so popular, as wood is natural, beautiful, stylish, durable, and easy to work with.
Despite the versatility, how rapidly wood burns can be worrisome. It is also the most common material of choice for handles of kitchen items that get hot such as stirring spoons, ladles, pots, and pans, which makes its heat resisting capabilities kind of confusing to many.
So, is wood heat resistant? Wood is not heat-resistant. It has poor thermal conductivity and is made of organic carbon molecules which makes it highly flammable. However, there are certain treatments and coatings you can use to make wood more heat-resistant.
That, however, shouldn’t stop you from making it a top choice in your building, structures, fixtures, and crafts. There are multiple ways of upgrading your wood to make it heat resistant, and this article is the ultimate place to learn more.
Hop on as we guide you through the various ways of making wood heat-resistant, as well as choosing the best wood for heat-resistance and those to avoid.
How Do You Make Wood Heat-Resistant?
The continued widespread use of wood in homes and commercial spaces is an indication that there is a solution to the problem in question.
Clearly, there’s something that is being done to elevate wood’s resistance to heat and fire. Perhaps a heat-proof wood treatment exists? Unfortunately, no. As much as that would be a dream come true for many, there’s no way of making wood 100% heat-proof.
However, there are ways of protecting your wood to increase its level of heat-resistance and reduce its susceptibility to combustion. Here are several ways of doing it.
1. Homemade Heat-Resistant Spray Treatment
You can prepare a heat-resistant wood treatment at home. There are two mixtures you can make depending on the supplies you have access to.
- Borax or sodium borate
- A crock-pot you no longer use in the kitchen
- A container for the mixture
- A spray bottle
- Gloves and apron
- Don a pair of gloves, an apron, and other protective clothing as you’ll be working with chemicals.
- Start by boiling 1 cup of water in the crockpot. Once the water is boiled, turn the heat off.
- Add half a tablespoon of borax to the hot water. Stir the mixture well until the borax is dissolved completely.
- Now allow the mixture to cool down to room temperature undisturbed. You can use a thermometer if you have one.
- Some borax will be visibly settled at the bottom but don’t bother to stir it up. You are only interested in the clear solution.
- Decant the liquid into a separate container, then pour carefully into a spray bottle.
- The next step is to wet your wood with plain water thoroughly, then spray copious amounts of the mixture on it.
- Let it dry and repeat once more or twice. You’re aiming for complete saturation, so ensure the wood sucks up as much treatment as it can.
- Zinc chloride
- Ferric chloride
- Boric acid
- Ammonium sulfate
- Measuring cups and spoons
- Wooden spoon or stick
- A spray bottle and a bucket
- Gloves and apron
- With your protective wear on, start by pouring two quarts of plain water into a bucket.
- Measure accurately and mix into the water a ¼ cup ferric chloride, ½ cups zinc chloride, and 4 tbsp of ammonium sulfate and boric acid, in that order. Do not touch the solution with your hands.
- Carefully stir the mixture using a wooden stick until all particles are dissolved.
- Transfer the solution into a spray bottle and spray several coats onto the wood before allowing it to dry completely.
While these DIY heat-resistant treatment methods work, they are not permanent. The coat can be wiped out or washed away by wetness or moisture, wearing out that heat-resistant effect. For a more long-term solution, you have to look at other ways of making wood heat resistant.
2. Heat Resistant Coatings
Commercial heat and fire-retardant coatings are more effective than their homemade counterparts but come with a matching price tag. The application, however, must be done professionally for the best results. The one we’ve linked to above is even mixable with paint to create a sealed layer of fire-retardant paint.
The fire-resistant coating is usually transparent. It allows the beauty of the wood to show through if you don’t want to use fire retardant paint which is the next method of making wood heat-resistant.
Some finishes such as varnishes, urethanes, shellacs, and epoxy provide wood with varying degrees of heat resistance too.
3. Fire-Retardant Paint
Fire-retardant paint is an excellent way to counter wood’s vulnerability to heat and flame. This paint is designed to be heat resistant and flame-retardant. So, if you want to minimize the risk of fire for your wood, avoid the other highly flammable kinds of paints and opt for this.
How do fire retardant paints work? Fire retardant paints resist heating up to certain temperatures. In case of a fire where temperatures are extreme, this paint pops up into a layer of foam or carbon.
This layer is five to ten times thicker than what the initial film of paint was. It resists flames and acts as a protective barrier for the wood beneath, delaying combustion of the wood for up to 40 minutes.
There are other types of fire retardant paints that work differently. These produce non-combustible gases that slowly suffocate hungry flames of oxygen.
You can also opt to create your own fire-retardant paint by using a fire-retardant paint additive in your regular latex paint.
What Type Of Wood Is Heat Resistant?
No type of wood is 100% heat resistant. Any wood will eventually burn at some point. Notwithstanding, some types perform way better than others when it comes to resisting heat and flames.
If you are going to select wood, you are likely interested in knowing what is the most heat resistant wood? Azobe is the wood species with the highest heat-resistance.
Azobe is ironwood, and tree members of this wood family are known to be good at resisting heat. Cumaru is exceptional as well and is rated as class A. Other wood species that perform exceedingly well when it comes to heat-resistance are birch and cedar.
Generally, hardwoods will resist heat far better than their softwood counterparts. That’s because they are dense, thick, and have fewer pores. These characteristics inhibit combustion. The likes of oak, maple, walnut, mahogany, and teak make some of the best woods for heat-resistance.
Composite boards such as plywood, MDF, and OSB are also often engineered to be heat-resistant and fire-retardant. The process involves a combination of pressurized treatments with fire-resistant chemicals. There’s also the inclusion of non-combustible components like cement within its tightly packed fibers.
You can also get information on what class of fire index your wood belongs to. This classification helps you tell how good or bad it is at resisting heat. There are three classes, A, B, and C. Wood classified as class A has the highest level of heat resistance with a low flame spread score of less than 25.
Class B woods offer a medium level of resistance, while Class C woods have the highest flame spread score, provide the least heat resistance, and combust the quickest.
Should You Make Your Wood Heat Resistant?
Wood is all good until it is set ablaze. Remember, it takes a simple spark to raze an entire building, so you have every reason to make your wood heat-resistant.
Wood that is treated to be heat-resistant or has a low fire spread index makes it easier to manage the fire and even gives you time to grab the fire extinguisher or escape and let the professionals handle it.
Time is always of the essence in such incidents, and it is such measures you take that actually buy more time to act by stopping small fires from escalating and spreading much faster.
Fires aside, you may also want to make your wood heat-resistant to maintain its aesthetic quality. Take, for example, wooden kitchen countertops or dining tables.
These surfaces are always handling hot vessels. If such wood is not heat resistant, its beautiful appearance quickly becomes a memory, and you’ll only be left with ugly marks. Therefore if safety is a significant concern for you, then, by all means, make your wood heat-resistant. It minimizes risk, loss, and damage.
Wood is not heat-resistant. It is naturally flammable and will burn fiercely when ignited at specific temperatures.
Due to such vulnerability to fires (and consequently loss and damage) treating wood to give it heat-resistant properties is more of a necessity than personal choice if you are to continue enjoying it around your home safely.
You can treat wood to upgrade its resistance to heat. There are various ways of doing it using DIY or commercial heat-resistant flame retardant treatments, and finishes including varnishes and paints.
You can also make smart choices when selecting the wood. Wood from ironwood trees, hardwoods, heat-resistant-treated plywoods and lumbers, and every wood in class A are your best bet. Until someone discovers a way to make wood absolutely fireproof, these are the options to go by.
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