So the floor heat system is somewhat unusual. Details are:
- The house is 5x7m. The heated area is about 2.5x7m
- There is no concrete base. The system [1] I used was designed to receive concrete, but I decided against it.
- The floor heats up in about 30 minutes, but the water temperature is substantially higher than normal (because lack of thermal conductivity due to lack of concrete)
- The flooring is large plywood sheets[2]. Surface temperature is variable, 23-26deg.
- The heating is provided by a wood-burning 'bailarina' [3] [4] [5]
- There is no heat exchanger. The hot water that goes under the floor is the same as the hot water that comes out the tap. Not drinking the hot water is kinda normal for europeans though. The pipes may clog up with sediment in 5-10 years, but they are not concreted in so I'm not too bothered.
It may seem like there are some odd choices there. My priority was simplicity and being able to easily change things in the future.
Edit: clarity
Edit 2: If I was to do it again with more time and patience, I would pour in sand. It has about the same thermal properties of concrete, and is way less permanent.
>>> Edit 2: If I was to do it again with more time and patience, I would pour in sand. It has about the same thermal properties of concrete, and is way less permanent.
I did something similar when building a fence. The "proper" way to set the posts was in concrete, but I calculated how many bags I'd need, relative to my own strength and patience. Instead, I poured sand in, got it wet, and shook it to make it settle. The fence has held up for almost 20 years. The last few posts I ran out of sand and used dirt. They've held up just fine too.
I'm mostly curious about the cycle time. We install floor heat in our homes, typically with a gas-fired boiler.