Earth Tubing

Hi, I am looking to Build an earthship in the STL MO area out in the MO Bottom area 63114. I want to do earthtubing as my heating/cooling. The house will be 2400 sq ft (2 stories). I was thinking of using 4" or 8" x 20 ft. SDR17 HDPE Pipe (High Density Polyethylene Pipe). For heating I was going to use a cast iron stove and a fireplace as well. For the cooling I was going to use a dehumidifier to help with moisture in the tubing. From what I understand, a dehumidifier is essentially an air conditioner as well. I have been reading into your forums for little tips and tricks for actually installing the piping. What I was more so curious about was how many feet deep should I go into the ground? How many feet of pipe would be ideal to use. Is the soil in that area good for what I am trying to do? Is this ideal for MO area? Would it actually make a significant difference? It would be on acres of property so I could easily do horizontal tubing instead of vertical. I would be able to pre dig it all out myslef. But I would like someone with experience to help with laying it all out and the final design work. How much do you think that would cost roughly?

Gabe! Welcome to permies. Lots of threads here on earth tubes if you poke around. I dont think you can do any meaningful "heating/cooling" with earthtubes unless you have very low expectations. At best, you can temper your incoming outdoor air ventilation.

Some people in dry climates seem to do alright with these systems but in more humid climates, they are more risky and need to include a well thought out way of cleaning the interior surfaces of the tubes.

Thank you for responding Brian. I have been reading up on them, and from what I saw, they will not make a big difference as you said. But what temp should the air be coming out roughly in the summer time and winter time? I was thinking of using the rope and rag to drag through the pipes with bleach method to clean the pipes out.

Yes, it quickly gets complicated.

I'll throw one more complication in too.


A dehumidifier has two "sides", a hot side and a cold side. The cold side condenses water vapor in the air into liquid water to push humidity levels down. Yay!

But the net effect is to raise the air temperature, not lower it. Stated differently, there is more heat coming out than cold. It may very well still make a lot of sense to use one, but you won't get any cooling from a dehumidifier.


Geoff Lawton's latest free video shows a nice presentation of earth coupled heating/cooling in a greenhouse. Here's the thread about that;

https://permies.com/t/43078/geoff-lawton/Heating-glasshouse-geo-solar-live


finest regards,

troy

I agree with Troy there and extend the de-humidification aspects to the earth tubes. They may lower the temperature of the incoming outdoor air but they will probably not effect the humidity in any meaningful way. As you may know, AC makes things more comfortable with Sensible (air temp) and Latent (humidity) conditioning.

The temps effected would depend on a number of variables: Outdoor air temp, ground temperature, CFM through tube, length of tube, diameter of tube.