The Ultimate Guide to Building Your Own Custom Infrared Sauna
Should You Build Your Own Custom Infrared Sauna?
If you have the means and desire to build your own infrared sauna, there is no better way to get exactly what you want than by designing your own. In fact, I would design my own sauna over purchasing a portable unit one hundred percent of the time. Not even close. However, there are some things to know before you dive in on your own.
Before I built my own sauna, I did all the research, looked into the types of wood, heaters and accessories and concluded I would combine my findings with some professional assistance. This turned out to be a great success as I got exactly what I needed and the price was essentially the same as purchasing one of the biggest portable units on the market.
The first place to start is to find out where you want your new custom sauna to go. Technically you can use just about any space to design and fit your infrared sauna into. However, my suggestion for your sauna would be an extra bathroom, an unused laundry room or walk in closet. I had a couple of options—I wanted to use the smaller of two spaces I had available and I decided upon an extra closet as opposed to entirely taking over one of my extra bathrooms. The closet was a nice size – 5’ x 7’ x 10’. It was windowless but still had enough room for a deep bench and floor space.
The first thing that I learned was that my ceiling was too high. While infrared works by raising your core temperature, there is still some need to have the air temperature in the 110 – 125 F range. If your ceilings are above 8 feet, the hot air will rise and not allow for the room to properly heat. For this reason, we always recommend framing the room off so it is no higher than 8 feet. Ideally, you would do 7 or 7.5 feet. I chose 7.5’ Once you decide on your space, it’s time to choose which type of wood you want to use in your sauna.
Select Your Wood
The next thing to consider is what type of wood do you want to use in your sauna. The wood choice is not only important visually it is also the component that insulates and keeps your sauna environment clean. Because of this, I didn’t want just any wood—I really wanted cedar. I did look at poplar, aspen, basswood, fir and my second choice, spruce. However, I chose cedar for its beauty and anti-fungal/anti-microbial features. Cedar is the most common sauna wood because it’s the softest and it keeps itself the cleanest. Additionally, if you ever need to clean it, you can always just sand it down.
However, cedar is also the most expensive. All the woods I looked into had their own benefits and disadvantages but it finally came down to cedar as if it gets stains on it, it is the easiest to sand.What you will need to take into consideration is that you will be lining your sauna with cedar wood: on the four sided walls, the ceiling, the floor and the bench. My company, DIY Infrared Saunas, sells tongue and groove cedar wood that is very easy to install. However, it is not cheap because we cut the wood do different lengths for you as well as you always have to factor in the cost of shipping.
The different lengths and types of wood that we sell are the following:
Western Red Canadian Cedar: 6’, 7’, 8’, 10’
Clear Heart Redwood: 7’, 8’
Nordic Spruce: 6.83’
Canadian Hemlock: 6’, 7’, 8’, 9’, 10’
How to calculate linear feet:
In order to calculate how many linear feet you will need of wood you will want to measure the total length of feet in the room. A linear foot is no different than a foot (for example six linear feet is equal to six feet—nothing special). However, when you select your wood start to add in wooden boards to line your sauna’s walls with, it gets a little more com-plicated. Let’s look at this sauna design for example. (This is purely an example and if you don’t feel like you need to learn linear feet, you can feel free to skip this section).
start to add in wooden boards to line your sauna’s walls with, it gets a little more com-plicated. Let’s look at this sauna design for example. (This is purely an example and if you don’t feel like you need to learn linear feet, you can feel free to skip this section). The total space for this sauna in feet is 12’ long x 10’ wide x 8’ tall. Getting the right amount of linear feet for each wall is needed to be able to calculate how many wood boards you need for the walls, ceiling and floor.
Here is the sauna wall by wall: (the boards that we sell come in 6’ to 10’ lengths and are 3.5” wide by .5” thick. Let’s say, for this example, that we are using 8’ cedar boards and we are going to lay them horizontally).
Left wall: 10’ linear feet total (120”). The room is also 8’ high (96”). 96” di-vided by 3.5” equals 27.42 horizontal boards. On each board you will still need an addi-tional 2’ to cover the empty space. 2’ linear feet for 96” divided by 3.5” is still 27.4 boards, but now you can divide that by 8’ sections and cut 3.4 8’ boards into the 27.4 boards you need to cover the wall. I would personally just purchase 10’ boards for this wall, but every build is different. You’ll also want to criss cross the wood to make it 5GALLERY 2.1
look best; meaning, have one two foot portion on the left, then one on the right and so forth.
Total 8’ boards = 30.8 (31)
Right wall: same as the left wall above.
Back wall: 144” linear inches (12’). Because the room is 96” high you will need to divide by 3.5” for a total amount of 27.4 boards. However, instead of 2’ of left over space, now you have 4’. So the amount of boards you will need to cover that empty wall space will be double (6.8 [make it 7 to be safe] boards cut into 4 12” pieces each equals 27.2  horizontal pieces of .
Total 8’ boards = 34.2 (35) boards
Front wall: The front wall will be similar but you must factor in the door. Let’s say you have a door that is 3’ wide by 7’ tall. That means you subtract 36” from 144” and you get 108” linear inches. However, the door is perfectly centered in the room so it will be 54” on each side for the first 7’ vertical feet. 7’ is 84” divided by 3.5 is 24 boards that you will need to stack on each side. If you cut 54” (4.5’) from an 84” (8’) board you will be left with 24 30” (3.5’) board sections. That leaves one side of the door (let’s say the left side) completely covered (up to the height of the door) and then 30” boards covering all but 24” on the right side of the door. Because you need 2’ wide and then 7’ high you can cut 6.8 (7) 8’ boards into 24 2’ pieces.
You will still need to fill the top foot of space between the top of the door and the ceiling. This would be done by finding the linear feet of 144” by 12” high. Take 3.4 8’ boards and line the wall. You will now have 4’ of left over space. You can then take 2 8’ boards and cut them in half and finish the other side. The measurement won’t be ex-act because you need 3.4 boards to fit perfectly, not 4 boards. Just cut one board at 35.6 millimeters all the way down and use the smaller portion of the board.
Total 8′ boards = 39
Ceiling: The ceiling and the floor can be calculated the same way. Because the width of the room is 120” and the length is 144”, you will need 41.1 (42) 8’ boards 6 to line the ceiling. However, you will still be left with 24” of space that is 144” long. That means you will need 42 sections of 24”. You can get this by cutting 10.5 8’ boards into 24” sections and filling the space.
Total 8’boards = 53 boards
Floor: Same as the ceiling.
When you contact me regarding your future custom sauna, I will do all of the cal-culations for you; however, because this is DIY Infrared Sauna guide, I wanted to do my best to explain the complications with calculating linear feet as need to be able to count how many wooden boards you need per wall. It’s not as hard as you think and I am here to help you!
Decide on Your Bench/Backrest
Having worked in the infrared sauna industry for a few years before I designed and built my own sauna, I knew the importance of the bench and backrest. Plain and simple, if you are not comfortable in your sauna, you won’t use it. Comfortability is equally as important as any other factor. What I learned from the industry famous Clearlight Premier portable saunas was that you can build custom contoured benches and backrests. Because infrared heaters range in temperature from 140 to 400 degrees F, you will always need to cover them with wooden slats (see the image below). Why not have these slats be comfortable to lean on?
Here at Custom Infrared Saunas, we can custom make you these ergonomic benches and backrests specifically for the di-mensions of your sauna. To see an example, see the photo below. Do you see how on the right and left hand sides of the sauna the backrests are built into the sauna?
We can build you custom backrests and benches depending on the size of your sauna. I would highly recommend making the investment into having a comfortable bench and backrest. It makes all the difference in the world.
Choose Your Heater Type
For DIY custom saunas it’s very important to choose the right infrared heater. In order to help you decide, I am going to explain the positives and negatives to the three main styles of heater (carbon, ceramic, combination carbon/ceramic).
The most common objects used in an infrared sauna are carbon and ceramic com-pounds because they will hold and absorb the most heat. Here are photos of a carbon (left) and ceramic (right) heater.
The molecular properties of these carbon and ceramic heaters change when heated. When an object absorbs infrared energy it causes its molecules to activate and move. When they move, infrared energy is released in the form of invisible light. This is the basic explanation of how an infrared sauna works.
When you sit close to the infrared heat coming out of a carbon or ceramic infra-red heater, your body then absorbs the infrared energy, thus charging your body’s particles and raising your core body temperature.
For kicks, let’s get into the science behind how this works.
The scientific principle which proves that heat turns into invisible light is called Wien’s Law of Displacement.
Wien’s Law is a formula that provides the wavelength of the infrared light of a blackbody. A blackbody measures how much infrared an object can absorb from .00 to 1.0—0.0 being none and 1.0 being the highest amount. The heat which radiates off of a heated object is referred to as thermal radiation (infrared light!) and this is what is measured by Wien’s Law, shown here:
Wein’s Law of Displacement:
5268 / ( temperature °F + 460) = the Peak Emission Wavelength (PEW) of an ob-ject (measured in microns)
When you put in a temperature into the formula above, what is produced is an in-verse amount of heat to wavelength.
The hotter the object’s temperature, the shorter the infrared wavelength. The cooler the object’s temperature, the longer the infrared wavelength.
Let’s try a few temperatures:
5268 / ( 400 °F + 460) = 6.06 microns
5268 / ( 90 °F + 460) = 9.48 microns
A micron is just a unit of measure of infrared light. 1 micron=1000 nanometers.
The average skin temperature of a human is 90 °F. Because of thermal radiation, we actually put out infrared in the same way that any other object emits infrared. That’s right: human absorb infrared and we emit it. We just happen to put it out at 90 °F. Therefore, based on the formula, our Peak Emission Wavelength is 9.48 microns.
At this point you might be wondering how this works in the real world. When you are close enough to an object emitting infrared, your body will absorb it. You can actually do a test right now to feel infrared. Put your hands together, but don’t make them touch—Separate them about one inch apart. You will actually feel the infrared heat on the palms of your hands!
When your body absorbs infrared heat your core temperature rises. The caveat is that the longer the infrared wave, the greater amount that your body can absorb and the higher your core temperature can rise. The problem with this is that the longer the infrared wave, the cooler the surface temperature. So, you need a balance of the two. What is the best heater you ask? Let’s dive in.
In order to find the right object to use for an infrared heater, you must look at the molecular components that allow for the greatest amount of heat retention, or infrared absorption.
What the original inventors of infrared saunas realized is that a ceramic com-pound (ceramic is a naturally occurring mineral that comes from clay) lends itself to different states and shapes. Ceramic clay can be molded when wet, it can be dried to take forms of objects (pottery, bricks for buildings) or used to cook. When you heat it, its electrons start to move which generates heat.
In the infrared sauna environment, ceramic is a great conductor of infrared heat because its blackbody rating is closer to 1.0 than any other mineral or rock. What that means is that ceramic absorbs infrared better than any other object!
Its actual emissivity is .99.
Emissivity is defined as an object’s effectiveness in emitting energy as thermal radiation.
The perfect 1.0 rating doesn’t exist, however, ceramic is the best mineral to ab-sorb infrared and thusly has the highest emissivity (or potential infrared output) rat-ing of .99. This means that it absorbs the most amount of infrared which makes it an excellent source of infrared emission for saunas.
But there is a downside using ceramic as an infrared emitter.
The problem with ceramic is that it gets too hot. The absorption property of ceramic allows for its surface temperature to rise to 350 – 400 degrees °F. Let’s put this into our Wien’s Law formula:
5268 / ( 350 °F + 460) = 6.44 microns
The problem with this is that the micron level is not optimized to the body’s Peak Energy Wavelength of 9.4 microns (remember, we put out infrared at 90 °F; therefore, we best absorb infrared at 90 °F as well).
The 6.4 micron wavelength is too short for our bodies to optimally absorb it. It would be much better if we could find something that got hot enough to heat the body, but also had a longer wavelength of infrared light for proper absorption.
About seven years ago there was a significant innovation in the infrared sauna in-dustry—carbon fiber panels. The reason for this was that carbon fiber is more malle-able than hardened ceramic and its surface area can be spread out and expanded. By expanding the total surface area this would lower the surface temperature and allow for a longer infrared wavelength—it’s also much cheaper to manufacture.
So what’s the surface temperature of carbon panels in infrared saunas? About 140 – 150°F. Let’s plug that temperature into Wein’s Law:
5268 / ( 150 °F + 460 ) = 8.55 microns
Carbon fiber panels have a much longer infrared wavelength. Seems better, right? Not necessarily. Carbon fiber doesn’t allow itself to absorb as much infrared as ceramic. So its blackbody emissivity rating is closer to .94 or .95.
Let’s say you were standing in the sun wearing a black shirt, which absorbs 99 percent of the infrared light coming from the sun, whereas a light blue shirt absorbs 94 percent of the infrared light. The black shirt gets much hotter because it absorbs more infrared light.
This is the difference between carbon and ceramic. Carbon simply does not get hot enough in an infrared sauna environment to raise core body temperature on its own.
As we have already gone over, the difference between an infrared sauna and a traditional sauna is that an infrared sauna relies on the changing of the internal proper-ties of objects to exude heat in the form of invisible light (thermal radiation). This light is absorbed by your body and your core body temperature rises. As a result, you produce a deep sweat—your body’s natural mechanism to cool itself.
Traditional saunas heat the air (and the water in the air), which then heats your skin. If you want hot air, get a traditional sauna. If you want to heat your body, get an infrared sauna. In the same way that traditional saunas do not heat your core body temperature enough to allow for the health benefits they are capable of providing, car-bon infrared panels do not get hot enough to heat your body’s core temperature.
As a result of the low surface temperature of carbon, sauna companies have to in-crease the carbon panel surface area even more to heat the air above your head to simulate getting a good sweat. Yes, having enough heater surface space in the sauna can raise the air temperature in the sauna. However, by doing this, it is no longer infra-red light heating your body; but rather hot air convection, the same as traditional sau-nas. The effect of raising the air temperature to overcompensate for low surface tem-peratures and underpowered heaters is not the goal of infrared saunas.
Because infrared energy is actually invisible light, it can be described in the same manner as a flashlight that reflects light in a certain direction: Light from a flashlight travels in a straight line, which is true of invisible light as well. You can think of infra-red panels as giant flashlights reflecting infrared light in a straight line.
The goal is to reflect this light into your body in order for it to be absorbed which creates a rise in core body temperature, which is infrared sauna therapy in a nutshell. When carbon panels are positioned above your head, they are effectively reflecting this light into thin air and the infrared energy is wasted. Unfortunately, the person in-side the sauna is often fooled as they feel heat because the air temperature will rise.
The debate of ceramic vs. carbon heaters can be summarized in a single sentence:
Ceramic heaters run too hot and carbon heaters don’t run hot enough.
Combination Carbon and Ceramic Heaters
Seven years ago, while carbon panels were becoming more and more popular, the first combination carbon and ceramic infrared heaters were also developed. Re-member that ceramic is pliant and lends itself to many shapes.
What would happen if you mixed carbon with ceramic and got the best of both heaters?
The result was the most effective infrared heater ever created. By mixing carbon and ceramic together, you get a more emissive heater than carbon at a much cooler temperature than ceramic. You also get a longer, deeper penetrating infrared wave-length. Because the chemical properties are now mixed, you get a blackbody absorption rating between that of carbon and ceramic combined—95 percent (carbon) + 99 percent (ceramic) = 97 percent.
This blackbody absorption rating allows the combination carbon/ceramic heater to hold a hotter temperature of 200 degrees °F (the ideal temperature for an infrared heater); something that was not possible with either carbon or ceramic alone. Let’s input 200 °F into our formula:
5268 / ( 200 °F + 460) = 7.90 microns
This means that the infrared wavelength is pretty much right in the middle of carbon (9.4 microns) and ceramic (6.0 microns). The PEW of the carbon/ceramic heater is 7.90 microns, but remember this is just an average which can be expressed by a bell curve.
As you can see, the peak emission wavelength is right at 7.90 microns, however, you still have infrared waves traveling at 6.0 microns and wavelengths traveling at 9.4 microns. Why is this important?
Our bodies are made up of over 70 percent water. Different molecules in your body are going to accept and absorb different infrared wavelengths. The shorter the infrared wavelength the deeper that it can penetrate into your body. The longer the wave-length the shallower it gets absorbed.
The water molecules in your body absorb a greater amount of infrared than any other molecule in your body. (Water actually absorbs the highest amount of infrared energy on the planet, and without water’s ability to absorb infrared, we’d be in a continuous ice age).
The greater amount of infrared energy that your body receives, the greater the amount that will be absorbed by your body’s water molecules. (The different molecular types in your body are water, protein, connective tissue, fats and carbohydrates—98.7 of these are water molecules).
Because a ceramic heater has an emissivity of 99 percent (versus 95 percent emissivity of carbon) more of it will be absorbed by your body’s water molecules and your core body temperature will rise faster. The more infrared light, the more energy is absorbed by your body.
All things being equal, you will get a much better sweat in an infrared sauna in a pure ceramic sauna than a pure carbon. The reason is because ceramic puts out more infrared energy for your body to absorb.
From my own experience and hearing hundreds of stories throughout the years, carbon doesn’t put out enough infrared energy to be absorbed by your body. Your experience and resultant health benefits will be much slower to appear because of it.
So what is the reason for a combination carbon and ceramic heater? An even distribution of infrared light around your body and a more tolerable temperature to allow for you to stay in the sauna longer. This allows for you to sweat for a longer period of time and effectively detoxify your body.
All things being equal, in a custom infrared sauna, I would choose combination carbon/ceramic heaters. The most important factor for receiving health benefits in an infrared sauna is raising your core body temperature. As a result, your body will excrete toxins, lose weight and recycle old cells, so you must have a sauna that gets hot.
The best surface temperature to heat your body and penetrate deep into your tissue is 200 °F. This is only provided by the combination heaters.
Choose Your Power Supply and Controller
Each power supply that we provide allows for 1800 watts per dedicated 15 amp circuit or 2800 watts per dedicated 20 amp circuit. Also, we aim for 17 watts per cubic foot of your sauna. So if you have a sauna that is 300 cubic feet and multiply that by 17, you end up with 5100 total watts. That means you will need two 2800 power sup-plies each running on 20 amps or three 1800 watt power supplies running on three 15 amp circuits.
I used to believe that 110 volt and 120 volt plugs were the same but they are not. 110 volt plugs have the two vertical plugs and 120 volt plugs have three prongs (with one horizontal and one vertical). Make sure you have the right plugs in place for your sauna’s power requirements. If you have any questions please give us a call at (530) 417-1220 or call your local electrician.
Would You Like Accessories?
There are some really great accessories that you can put in your sauna to optimize your experience. Here is what I have installed in the past.
Temperature and humidity gauges – Gauging the sauna room temperature is convenient and is included in the control panel of the sauna. However, it’s really good to have a good thermometer in the sauna. Humidity gauges are usually not necessary for infrared heat.
Timers and hourglasses – Timers are necessary and also usually built in however, this is an essential accessory.
Racks, shelves and hooks – A couple of well-placed shelves and hooks can al-ways be a big help. If you want to stack clean towels and bench pads these would be useful. You can also stack towels outside of the sauna or under the bench.
Towels and wraps to cover up and dry yourself – Clean towels are necessary to keep your sauna’s wood clean. I always recommend putting a towel down on the bench and on the floor so you don’t sweat directly on the wood. This will help to keep your sauna clean. It’s not the end of the world if you do end up with some sweat on the wood; usually you can just wipe it off with a damp cloth or towel. If it gets really bad, you can just sand the wood down to where it looks brand new.
Brushes, simulated birch branch whisks and soaps to stimulate circulation and exfoliate and hydrate the skin – For stimulating blood circulation to the skin and rubbing off dead skin cells (exfoliating), brushing the skin or smacking it with leafy tree branches is an age-old sauna custom. Nowadays, a loofah sponge is also popular.
CD players, stereos, speakers for music – There are several sauna music accessories for WiFi hookup and recharging cords that make a lot of sense nowadays. Music speakers and a CD player are nice, as well. I would personally go with a stereo and speaker system installed in the roof of the sauna with the stereo player under the bench. You can then run an ipod or pandora/spotify off of your phone using bluetooth or AUX cable.
Recessed lighting – My favorite look in a sauna environment is dimmed/indirect light. You can either recess the lights in the ceiling or you can install light fixtures on the walls.
Materials to keep the sauna clean and dry – Commercial sauna cleaning products are available however some diluted hydrogen peroxide and water in a spray bottle works well to keep the interior of the sauna clean and bacteria free.
Color light therapy and special fragrances – Color therapy and fragrances are also pleasurable. Sometimes the interior sauna lights are too bright so varying colored lights provide health therapy along with easing eye irritation.
Before purchasing any heater or taking a single step to actually build your sauna, contact your local building code authority. In some localities, only certain heaters are approved, or they must be installed in a particular manner. Size, location or the wood used may be included in code restrictions. Some areas may even require you to purchase a building permit and to have the building inspector approve the installation once you’re done. Since a sauna isn’t used for living space, most building codes aren’t as restrictive. But a quick check with the building code department will ensure you get to use your money for the sauna – not for fines and penalties.
You will also need a professional to install commercial gas heater systems and hook up the gas supply to the main gas line, and another to perform any wiring needed. Even with a gas powered sauna, you’ll likely want an interior light and possibly other electrical items near or inside the sauna. The intense heat and humidity is tough on electronics and wiring. An electrician will seal and insulate all the wiring and install light fixtures designed for use in a sauna.
We have years of experience installing infrared saunas in all sorts of spaces and businesses. If you have a question, we have the answer. Please give us a call at (800) 370-0820. It would make me very satisfied to help your dream custom infrared sauna a reality.