[NCalHippie]

The cheapest construction that I have found is dry stacked cinder block with every 3rd or 4th hole with rebar and filled with concrete. Coated inside and out with surface bonding cement. Very cost effective, fire resistant (nothing is totally fire proof), decent thermal mass if the holes are filled with dirt. Metal trussed roof with metal roofing.

For cooling, I would run 12" galvanized pipe at least 4 foot underground on a downhill angle, with floor vents inside and a roof vent at the top of the roof to vent heat out and pull the cool air in.

Plumbing and electrical aren't that expensive to rough in when you are building but could be a hassle after the fact.

 

[NCalHippie]

Arendels house and plumbing is very roughly what I have in mind although smaller, rectangle, and one floor (+ partial basement)

The closer you build to a square, the more square footage you get per dollar of wall cost.

 

[NCalHippie]

Do you mind NOT sparing me the details? We use a sawdust toilet in our "cabin"(rundown trailer house in the woods), ice shack and camper. Other than using quite a bit of sawdust it works quite well. If we didn't usually have a large supply of sawdust handy it would be a problem. In fact, one time as a test we left a half full bucket at the "cabin" in the summer to see if it stunk in two days when we came back, two days became three weeks and I was very worried about what it would smell like. When we got back there the "cabin" didn't smell at all and emptying the bucket had a bit of an ammonia smell that is usually doesn't. I will admit when we tried using less sawdust the smell became a problem when we forgot a bucket in our camper.

My question is, where do you dump those buckets? It is sure to add up substantially and is not considered safe for composting edible plants. And yes, I have read the humanure book, just not convinced that it is safe.

 

[NCalHippie]

The gravity fed system if used as a greywater system would probably make sense to feed part of the system from rainwater... as you wouldn't even need to pump just fill with gravity from rain.

That raises the issue of having a roof that is both washable and non contaminating.

Gravity feed will get you about two pounds of pressure for each foot of drop. So you need your tank 10' above the faucet to get 5 pounds of pressure, barely a trickle. Get an RV 12VDC water pump and you can pump from a floor mounted tank instead of having to reinforce the ceiling to hold the weight of the tank. A 200 gallon tank will weigh about 1600 pounds when full.

 

[NCalHippie]

I'm a little confused are you saying that you won't get running water if you have a tank above your area or are you trying to feed from above by pushing water underneath your sink.

You definitely will get tons of water if you put a tank above and create flow from above to below.

Can you explain more in detail? are you talking about feeding an entire plumbing system or just feeding an outlet? Water creates a whole lot of pressure just one 1ft diameter pipe by 10 feet length will create a whole whole lot of pressure, enough to kill someone.

Sure you will get water, just not much pressure. Yes, if you use 1ft diameter pipe, you will increase volume, but not pressure.

 

[NCalHippie]

I see. So it would make more sense in an underground home to build a mound or build it into the side of the hill on atleast one side (perhaps using runoff from the hill can be collected - since this hill could support a cistern much easier than the building itself, it could also be used for terrace farming. If a large cistern that way 10 or 20 feet higher than the feed point of an underground home was a 6 foot x 6 foot x 6 foot cistern, this would yield 6X0.4*10 or 24 psi enough to run sprinklers and almost the same pressure as municipal water supply. Meanwhile if this were 20 feet higher, such as on a underground home subfloor such as for a shower it would yield 48 psi as much or more than many municipal water services. Meanwhile artificial pressure might becreated by having a wooden floating lid that could exert some force on the top of the cistern when it was not full. I could imagine building a concrete cistern or multiple cisterns into the side of a mount/hill .. meanwhile flow itself might be directed by channels away from the home or into secondary resevoirs that might behand pumped or run at low pressure. I imagine some type of screen or filter would also need to exist, to collect particulate runoff.

This is what I just sort of threw together

https://imgur.com/a/0DKVjl8

The slopes on either side could be used for terrace growing.

Not sure how not cheap it would be to run http://canadaculvert.com/ however masons built arched underground channels with available stone.

I have always liked the idea of terraced gardening myself.