This is the definitive guide on how to construct a clay pot heater to lower your winter heating costs.
A quick DIY heater made from a terra-cotta flowerpot upcycled will add warmth and ambiance to your outdoor space. These portable, simple-to-make, inventive, and inexpensive outdoor heaters are available. Use them as a source of heat on your patio or lanai, at a fall picnic, or while tailgating with friends.
We’ll cover everything you need to know about terracotta clay pot heaters in this article, including how to make them, which materials work best, and how to set them up safely.
Let’s look more closely at how to construct your clay pot heater.
Table of Contents
How to Build a Clay Pot Heater
In this post, we’ll show you two kinds of Clay Pot Heater: Tabletop Terra-Cotta Pot Heater and Hanging Terra-Cotta Pot Heater
Make a Tabletop Terra-Cotta Pot Heater
The traditional terra-cotta heater design is easily constructed from a few readily available materials.
Tools and Materials:
- one terra-cotta pot
- two terra-cotta saucers
- three bricks
- tea light candles (burn time: 3-5 hours)
1. Put one of the terra cotta saucers on top of one of the bricks and place it flat on the table.
2. Invert the terra cotta pot onto the two bricks that have been laid out on their sides, two more bricks, one on each side of the saucer. There should be 1″ to 2″ of airflow between the upside-down pot and the lower saucer. The heater’s warmth will be distributed more evenly and the candle will continue to burn thanks to oxygen.
3. An upside-down terra-cotta saucer can be used to cover the hole on top, which is typically the pot’s drainage hole. A coin or even a piece of tin foil can be used in the absence of a second saucer.
4. Place a few tea lights on the lower saucer and start them to burn. Four tea lights may generate enough heat to quickly melt the candle wax, as opposed to just one, which will only provide a little bit of warmth. Decide on the degree of heat.
5. The heater will become comfortable to the touch in a few minutes, so relax. It won’t take long for the area to begin to feel warm from its radiating warmth.
Make a Hanging Terra-Cotta Pot Heater
If you don’t have a table, no problem. Take the idea a step further and create a hanging heater for compact outdoor areas. Your heater can have more color and pattern added by using a ceramic bowl as the base. To add warmth and ambiance on a cool evening, hang it from the ceiling of your patio, from a pergola, or from a freestanding planter hook in an outdoor garden.
A threaded rod is used to construct a flowerpot heater that hangs.
Tools and Materials
- ovenproof ceramic bowl
- drill
- glass-cutting drill bit (3/8″)
- terra-cotta pot
- 18″ threaded rod (3/8″)
- nuts and washers
- tea light candles (burn time: 3-5 hours)
1. Make a hole in the center of the bowl using the drill bit. Thread a nut and washer to the bottom of the 18″ metal rod and place it in the bowl, edges up, on top of the washer.
2. In order to move the bowl toward the rod, twist one more nut. Put a washer on the rod that is snugly fitting. The planter made of terra cotta can now be lowered onto the rod and placed atop the washer. To close the hole in the planter, add another washer and nut to the pot’s top.
3. To make it simple to hang the heater, attach a connector and hook to the end of the rod.
4. Adjust the terra-cotta pot’s position as necessary, then place candles inside the ceramic bowl. To encourage airflow, leave an inch of space between the pot and the ceramic bowl.
5. Hang the heater and start the candles. Warmth will spread in a matter of minutes!
Clay Pot Heater Precautions
Don’t leave them unattended, just as you wouldn’t with any candle flame. Pets and children should be kept away from the flames by using the screen, but always keep an eye on them. The cookie sheet will help control the liquid wax flow that candles can sometimes cause. Check on your candle frequently to make sure the wax isn’t piling up. Frequently burning candles can use oxygen. Open a small window or the door once in a while if your home is airtight. Natural candles won’t produce much smoke, but if the situation lasts for a while, you’ll need some airflow. Do not leave your candle burning while going to bed. When using candles, take any safety measures you would normally.
Only use this as a heat source in an emergency. Go to an emergency shelter if you anticipate having your heat out for an extended period of time. This device can prevent you from freezing for a few hours at a time. The heat from your body can be kept close by layering your clothing and cuddling up under a blanket.
How to Arrange the Different Pot Heater Parts
Get your safe surface ready first. I use a tiny stone slab I found in the garden, but you could also use a plate.
Next, place at least two bricks around the secure area to support the upside-down flowerpot. Make sure there is enough space between each brick if you use more than two to allow air to reach the candles.
Additionally, check that the bricks are not too high; if they are, the candle’s heat will disperse and not reach the flowerpot.
Put the candles on your secure surface. In order to ensure that heat builds up inside the flowerpot, the candles should be just one or two inches below the opening.
Turn your flowerpot over, then set it on the bricks.
On the secure surface, place a few candles below the flowerpot. In general, I advise beginning with one or two candles. After that, you can observe how much heat they produce and decide whether you need to add more candles.
To build and perfect your flowerpot heater, experimentation is essential.
How Much Heat Does a Flowerpot Heater Produce?
When tealights are used as candles, a flowerpot heater generates about 50W per candle. More power is produced by bigger candles. A small room needs at least five candles to be heated. That is the same as an electric space heater set to low.
The average candle generates 80W of power, according to my guide to heating candles and thenakedscientist.com.
This amount can be calculated by taking into account the heat energy contained in 1 gram of candle wax, which is 37 Kilojoules, and then calculating the amount of wax burned per second. An average candle burns 0.5 milligrams of wax per second.
Should You Use a Clay Pot With Or Without a Hole?
flowerpots come with and without holes.
Pots without holes have a higher heat capacity and retain heat for a longer period of time. However, due to the restricted air supply, a closed flowerpot’s candle burning rate and, consequently, heat output are relatively low.
On the other hand, flowerpots with holes enable candles to burn more quickly and generate more heat because the air will flow through the hole as heat rises.
Heat can exit more quickly due to the hole. As a result, your flowerpot heater’s overall heating capacity decreases. In addition, you will need to replace candles more frequently due to the faster burning rate.
Which should you use, then?
Use a flowerpot with a hole in it for maximum heat production. Use a closed flowerpot to ensure that the candles burn for the longest possible time.
How Many Candles Do I Need for My Room Size?
Let’s look at how many candles are required to heat a room now that we know how much power a flowerpot heater can generate.
A typical candle generates 50W of power in a terracotta pot heater, according to an earlier experiment I conducted.
There are different scenarios that determine the number of candles you need:
- in an emergency situation you need only a few candles
- to heat to comfortable temperatures you need more candles
Let’s take a look at how many candles you require for comfort and emergency situations based on the size of the room.
| Comfortable temperature | Emergency | |
| Small bedroom (132 square feet) | 10 candles | 5 candles |
| Average bedroom (224 square feet) | 20 candles | 10 candles |
| Average living room (340 square feet) | 30 candles | 15 candles |
I used an average candle power of 87W to determine these values. I assumed that in order to maintain a cozy temperature in the winter, large spaces like typical living rooms would need 1500W. On high settings, an electric space heater generates roughly that much power.
A typical bedroom requires 1000W of power, while a small bedroom only requires 500W.
I have reduced the power requirements and, as a result, the number of candles for emergency situations by half.
How to Improve Clay Pot Heater Safety
Clay pot heaters are inherently dangerous. They can set off other items in your room because they have exposed hot parts, like the clay pot itself and open candle flames.
A flowerpot heater can also be very easily knocked over. Each component is only meant to balance on top of the others; none of them are fixed.
Additionally, the oxygen in your room is depleted by the candle’s flames.
Here’s what you should do to improve your terracotta pot heater’s safety:
You can lock the flowerpot heater in an empty bird cage. By doing this, you can prevent access by kids and animals.
It is still very prone to toppling over, though, even in a cage. The cage can collapse with just one bump.
A few bent metal rails and screws will help keep your pot heater from toppling over.
However, you are not required to take these safety measures if your home is not occupied by kids or pets.
Make sure to regularly vent the room as the candle flames slowly consume the oxygen.
I advise letting off steam at least once an hour. The benefit of flowerpot heaters is that the room does not get overly cold from venting.
The flowerpot serves as a heat storage device. So you won’t get much relief from a one-minute cry for help.
Which Types of Candles Should You Use for a Flowerpot Heater?
The best candle for flowerpot heating is inexpensive, long-lasting, and the right size to fit under a flowerpot.
First, let’s look at candle types suitable for flowerpot heating:
Tealights
The tealight candle is my go-to choice for flowerpot heaters. They are the most affordable option and are very cheap.
In addition, tealights have a sufficient amount of power and can be easily placed next to one another.
Tealights are packaged in thin metal cups, which maximize the amount of wax burned while also improving candle safety. In contrast, other candles without metal cups eventually burn out and leave a sizable chunk of wax behind.
You get the most heat energy for your money when using tealights because they burn completely out.
Pillar Candles
As their name implies, pillar candles have a thick wick and are extremely wide and sturdy. If you purchase them from the appropriate stores, pillar candles are typically inexpensive. Shops that sell clothing or home goods should be avoided.
Instead, look in low-cost hardware stores for them. There is no cup included with pillar candles. It won’t be possible to burn all of the wax, which is a drawback.
Nevertheless, pillar candles glow with a high rate of wax burning because of their thick wax and longevity because of the substantial amount of wax.
Because they burn for a very long time, pillar candles are ideal for flowerpot heating over night.
Do not use these candles:
Decorative Candles
I mean those long, thin candles that you set on your dinner table when you use decorative candles. They are decorative because their primary purpose is not as a source of heat.
Because of its thin shape, if you light one, it burns off quickly. However, their dimensions preclude the use of flowerpot heaters. They are also fairly expensive.
Scented Candles
Another kind of candle that you shouldn’t use for your terracotta pot heater is one that has a strong scent. They typically arrive in a cup, which is advantageous. They also have a big diameter, which makes them last a long time.
Scent candles, though, are expensive goods. We want to use the most heat energy possible while spending the least amount of money on it. For flowerpot heaters, scented candles are too expensive.
However, feel free to use one if you have one lying around and aren’t using it to heat. But never use scented candles for heating!
Which Type of Pot Should I Use?
You can use a variety of flowerpots. The best pot type supports the safety of your heater, evenly distributes heat, and is heat-resistant.
Clay Pots
To construct a candle pot heater, clay and terracotta pots are the best types of pots to use. Inexpensive and secure, they both. They can be easily replaced if one breaks.
Additionally, even after the candles burn out or when you vent your room, they have a large heat capacity and can hold the heat for a long time.
Ceramic Pots
Ceramic pots are very similar to clay and terracotta pots. They are secure and capable of holding a lot of heat.
They are more expensive to purchase because they are more elaborately made, more colorful, and glaze-coated.
You can make a candle pot heater out of a ceramic flowerpot that you already have at home, but I wouldn’t suggest getting one specifically for the purpose.
Concrete Pots
Hardware stores sell concrete pots for a reasonable price. However, concrete pots are frequently too large and weighty for flowerpot heaters.
Metal Pots
Making a flowerpot heater with metal pots is not recommended. Because of its low heat capacity, the thin metal quickly absorbs the heat and cools down afterward.
Metal pots also rust easily when heated. They have zero resilience.
Which Terracotta Pot Heater Types Are There?
Examining various candle pot heaters, let’s see.
Standard Clay Pot Heater
The typical clay pot heater consists of an inverted clay pot with lit candles placed beneath it.
The typical clay pot heater is inexpensive and easy to erect. However, it is dangerous to use and is not very effective at distributing and storing heat. You could compare it to sleeping with a hot stone.
Nested Pot Heater
A variation of the common pot heater called a “nested pot heater” involves stacking several clay pots of various sizes on top of one another. A layer of air serves as insulation between each pot pair.
Since the outer pot of the heater doesn’t get very hot, it has the benefit of being safe to touch. Additionally, because the mass of a nested pot heater increases, its overall heat capacity rises.
This indicates that this heater is better suited for use in areas with children or pets, and that when you ventilate your room, it will retain heat for longer.
The design of the heater has no impact on the heating effectiveness, which is solely dependent on the type of candle being used.
Nested pot heaters are also more difficult to install.
Engineered Pot Heater
A flowerpot heater that requires extensive technical design is known as an engineered pot heater. Here’s an example:
This type of engineered pot heater appears to be very promising. Additionally, they have a few benefits, including improved safety, directed heat flow, and increased heat output because of a ventilation system.
The design of the heater, however, cannot alter the candles’ efficiency. It is an unchanging physical constant. Therefore, heaters like this can only maximize the power of the candles by speeding up the burning process.
However, a higher burning rate necessitates more frequent candle replacement.
Build a wood stove or enhance your home’s insulation instead of designing a flowerpot heater. These produce much better results!
When to Use Clay Pot Heaters?
Making and using a clay pot heater only makes sense in an emergency when you don’t have access to heat. When there is a power outage, when you don’t have any heating, when you are in an off-grid cabin, etc.
In a workshop or garage, it might also make sense.
However, I don’t advise relying on clay pot heaters.
You must first have a lot of candles. Candles are expensive, typically costing more per Kilowatt-hour (kWh) of energy than gasoline, electricity, or other fossil fuels.
You will require a supply of about 40 candles to heat a small room with candles for a day. The worst part is that they are constantly out of stock, even when you need them urgently or because energy prices are going up.
I’m currently looking for candles online, but I can’t find a single deal that’s affordable.
Candle heating is unreliable. We primarily heat with oil, gas, electricity, or wood for a reason.
Additionally, having a stockpile of sturdy old wood at home rather than a large number of tiny tealights is much wiser in times of need.
What Are the Alternatives to Clay Pot Heaters?
Infrequently is it practical to use a clay pot heater. Wood stoves or propane heaters are preferable alternatives for heating in an emergency.
Install Your Own Wood Stove
The options for wood stoves are vast. Long-term investments in them are excellent. Even more so if you have the ability to chop your own wood, installing one once will pay off for a very long time.
In times of need, it is always much simpler to find wood in the woods than it is to look for candles that are out of stock.
Wood can be kept for a very long time.
Use a Propane Heater
In dire circumstances, propane heaters are an additional option to candles. I always recommend getting this propane heater (click here to view it on amazon).
Two propane bottles can be connected, and it can last for many hours or even days! Additionally, you can control how much the heater should heat up and you can release a lot more heat than you can with candles.
In addition, propane gas is very inexpensive, and you can keep a large propane tank bottle in your garden for emergencies so that you and your family will have heat for weeks or even months!
Oil Lamps
There are still petroleum lamps around. They were most likely in movies you’ve seen. Flea markets and garage sales both sell them. Perhaps you can find one online as well.
Oil lamps have the advantage of being simple to store and having a large enough flame to equal the size of a dozen candles put together.
This is just a thought I wanted to list, though. Sincerity be told, I still favor wood or propane!
Conclusion: Build a Clay Pot Heater
As you see, using propane heaters or wood stoves is a lot more scalable and reasonable to use in an emergency.
You shouldn’t use terracotta clay pot heaters as your main source of heat because candles are frequently out of stock during emergencies.
Nevertheless, it makes sense to construct a straightforward clay pot heater if you don’t have any other options.
Your heater doesn’t need to be over-engineered. It only requires a few candles, an upside-down pot, and a support for the pot.
Efficiency is not increased by creating a fancy engineered or nested clay pot heater! You will need to replace candles more frequently because it only affects how quickly your clay pot heater burns candles.
