So you want to have the same sort of effect on your body and mind in your home as you would in a commercial studio that perhaps I built.
First there are some considerations
1- heat – to heat a space to say 110 F. the walls floor and ceiling must warm up so if there is poor insulation you will be warming up the surrounding world nicely and expensively. So essentially we compare a hot yoga room to a walk in freezer . No-one would try to take a room but of Sheetrock or concrete and make it -10 F and use it for a freezer. Think of a Freezer- look at your own Fridge- knock on the interior walls- they are thin and backed with low density (weight) foam , Why? because it wont absorb Heat as easily as if it were build of High density materials. The reason a freezer can hold temperatures efficiently is because it has the ability to cool the objects you place inside rapidly and maintain that temperature difference compared to outside of the freezer . the more mass inside the freezer the more efficient it becomes . An empty fridge is an expensive fridge to operate. Mass holds temperature so if the space you want to use is concrete and tile or brick then you will have to expend an enormous amount of heat or energy to warm that mass. Once the mass is warmed it will tend to hold that temperature with far less energy . It could take days or weeks to absorb enough heat to warm a floor slab or a brick wall and often there is not anywhere near enough energy to achieve the desired temperature no matter how long the heat source in on.
Now what can you do? The least expensive method of heating is of course fire such as a wood burner or fireplace if those options are not viable then electric heat source’s are easily affordable and radiant sources are among the cheapest methods of heating. A 60 watt light bulb such as an incandescent or halogen lamp is a source of radiant heat as well are heating strips or resistive ceramic element baseboard heaters or even heating panels. Quartz heating lamps which glow orange or red produce a directional heat source of heat with intensity to make you sweat. I myself, used old radiant wire heaters with built in fans which i acquire used through the classifieds successfully for some time for a home practice but it required running extension cords from other rooms to keep from overloading my circuit breakers. Coupled with a misting humidifier 4 plug in heaters in a 12 x 12 bedroom can suffice.
For a dedicated hot yoga home space a room lined with at least 1/2” of foam on walls floors and filings is a minimal step which can allow a home yoga room to warm in minutes instead of an hour. I would suggest 2” of foam be used for best effect. in a 12’ x 12’ room a single heater can successfully warm the space in minutes while using only 1100 watts if it is a foam lined room, compare that to the same room with no foam and just Sheetrock and fiberglass R13 insulation which requires 5000 watts of heat to warm to yoga temperatures and could take an hour or more to get there.
Now there are ill health effects from using direct electric heat systems as when you use a radiant heater it radiates – Radiation ! All radiation is cumulatively damaging. A popular form of heat which is touted as a health giving heat is Far Infrared heat. There is much misleading claims associated with “Far Infrared heat” devices.
True Far Infrared is too subtle to be used for hot yoga ! One would barely notice the effect if it were true far infrared heat. What most confuse with true Far Infrared heat is Near infrared heat which has a damaging effect on the body and since it requires a light spectrometer to differentiate the actual light wave it is easy to dupe the consumer into thinking a device is Far Infrared when is really is not. For example a dermatologist may treat your skin with LED lamps which produce specific Far Infra Red and even UV light to be administered in a clinical controlled setting which barely warms the skin . Somehow heat panel makers are latching onto the idea that their panels which make you sweat 3 feet below them are as therapeutic . That is simply slight of hand BS. Direct radiation heat sources damage all living organisms and there is a strong correlation between radiation and premature cell death.
So what would you use?
A forced Air Heater is a safer and better choice provided the room is insulated with a low density surface such as foam insulation. If you don’t like the look paint it or wall paper it.
For Humidity a home user could get their hands on a large rice cooker or a commercial coffee urn and leave the top open -it will boil the water inside and produce more humidity than any home humidifier which only tend to make a paltry 380 ML for most. The more wattage a unit consumes the more the output.
I would suggest a carpet on the floor at minimum and prefer a insulated foam floor mat such as Zebra combo mat or Fuji Floor mat and 1” is best. if the entire floor is covered it will allow the room to heat faster.
The best home studios I have constructed have a High temperature, Custom Built, Forced Air Electric Furnace located outside of the yoga practice space coupled with a Heavy Duty Steam Humidifier and a Energy Recovery Ventilator to provide both Fresh Air during a session and the ability to exhaust the warm moist air following the session to help prevent mold or moisture damage. We have also used Bipolar Ion Generators and Large UV lamps for additional benefits with sterilization and air purification.
To our amusement there are many versions of equipment which resembles the methods or technology which we use which are completely ineffective and supplied to unsuspecting consumers. We only sell what is proven to work well.