Underground housing

bluesimplicity Hatfield wrote:I'm gonna see Mike in a few days.  I'm thinking it would be good to make a podcast with him.  What would be some questions you all would like me to ask him?


So many questions....

It seems to me an earthship is a first thought design. If you collected the rainwater from the shed roof in a cistern for drinking water, would you eliminate the problem of drainage?

Earthships have an atrium/greenhouse across the front. What are your opinions about that? I noticed you had one planned for your ridge home in the book, but I didn't see it in the video.

I live in a humid climate. How would you deal with humidity in an underground house?

Thinking about building a earth sheltered home near a quarry. Since the local materials are stone, would it be problematic to use stone instead of wood for the walls? I didn't know if the stones would settle or shift with gravity.  Would it be dangerous in an earthquake? Besides being local, I thought it would be a good passive solar material. Can you make an earth sheltered home passive solar? I didn't get the sense that Mike's homes incorporated passive solar.

How big can the uphill patio be realistically?

How deep does the earth need to be around the sides of the home to get the benefits of an earth sheltered home?

I too am very confused about the insulation. Rob Roy says insulate everything from below footings to walls to ceilings. John Hait says to insulate above the frost line and out 20 feet in all directions. Mike says not to insulate beyond the soil.

Nicholas Covey wrote:Paul invited me here, due to a beating I was taking at another forum. Closed minds simply couldn't get around the idea that I was bringing forth and the original purpose of my post turned into an argument, which I chose to stay out of. Paul stepped into the middle of it and argued in my favor, then sent me a PM to email him later.

I did so, and was invited here to tell my story....

SO here goes. This is the original post with minor changes...

I have posted parts of this on other forums, and have gotten a few answers here and there. I have sort of summarized my thoughts and findings. If you recognize this from other locations, I have refined what I have learned and brought a lot more content into the main post.

I have been looking into a (relatively) cheap way to produce a home for the last few months and I have most recently been looking into the Post-Shoring-Polyethylene method pioneered by Mike Oehler (of the $50 dollars and Up Underground House fame. www.undergroundhousing.com). I have his book and have read it cover to cover several times. It looks like a highlighter exploded in it now, with all the side notes I’ve taken.

Underground housing appeals to a lot of us for a lot of reasons. But it's typically a very expensive thing to do. So unless you have a rich benefactor uncle (don't we all wish...) its not usually a feasible thing. This may be a feasible way to build your hidey hole and still be able to afford ammo to defend it....

For those of you who aren’t in the know, I’ll summarize a bit. The basic principle is to take a heavy duty wooden structure (preferably designed to withstand the inward pressures of the weight of the earth involved) shore it up, and cover the outside with polyethylene plastic (I’m looking at pond liner myself). Then slowly back-fill dirt against the plastic and eventually cover the entire structure, leaving obvious spaces for windows, doors, etc. The dirt covering the plastic negates the damage that is typically done by UV and weather on plastic sheeting.

I'm in an area that receives about 36 inches of rainfall annually. I've located a hilltop on the property that I'm in the process of purchasing. My thought is to construct the structure practically on top of the existing ground (even if I have to haul in soil to do so) and berm soil up around and over it. I also want to put one big piece of poly sheeting over the top of it (and out from the house several feet, only about 8 inches under the soil) and create a sort of umbrella effect, so that most of the water will run off the sides. Most of the moisture should only get to the location by capillary action in the soil. I plan to use a lot of gravel (river rock) and sand, as well as a ton of plastic drainage tile to keep the water that doesn’t roll off the sides draining away efficiently. (there are three things to emphasize... drainage, drainage, drainage...)

I have access to a few wooded acres, a pile of (mostly) maple logs that have been ever so neatly stacked about a mile away, and a chainsaw or 2 (maybe three if I work on one). My wife works for a plastic manufacturer, so its likely that I may have access to some more inexpensive sheeting than average.

The design requires a few creative paths to provide adequate lighting so that you’re not living in a tomb (which is better than the usual path of south-facing windows and blank back wall, prone to leaks and dungeon-like gloom). Obviously a lot of emphasis goes into structure and drainage. A lot of emphasis also goes into design, so that there is adequate light and ventilation.

The design I'm working with makes use of light and ventilation in all directions, creating cross breezes, and utilizing the winter sun as often as possible. This would eliminate a lot of the usual underground house (dank cave/cellar) issues.

Rob Roy (a big name in the owner builder movement, better known for cordwood building than underground) suggests putting foam insulation around everything. His reasoning is essentially this: The ground is just thermal mass. It is a poor insulator. It cools and warms seasonally. By providing insulation around your UH you separate your thermal mass from the earth, which is prone to (slow seasonal) temperature swings that are not always within our comfort levels. 46 degree earth may not be cold when compared to the outdoor temperature of -15, but it’s still cooler than most people find comfortable as a living space. Ever sit on a 46 degree toilet?  Yeah, you know what I mean.

Rob uses the analogy that an underground house is just like an above ground house that's in a different climate. Instead of being in a climate where the temp may swing from the 100's to below zero, it rests in a climate where it gradually swings a few degrees over several months. That doesn't mean that the "underground climate" is a comfortable temperature all year round. Usually it’s a little on the cool side and the house needs to be insulated, otherwise its like trying to heat a tent in that same type of climate.

In short your heat is being bled off into the earth. If you insulate (and he suggests all six sides; even below footings if possible) then you keep your heat inside a small envelope. Add some thermal mass to keep your heat inside the envelope and a little heat goes a long ways. A small wood stove to warm the hands in the dead of winter may be enough BTUs to keep the whole thing heated. I plan to insulate about a foot beyond the walls (provided that I can keep that soil relatively dry) to provide adequate thermal mass so that I may not have to heat much at all.

I also wanted to note for those of you who are interested in these things, the water and power situations have been considered as well.

There’s a hill about 150 yards to the east that’s 35 feel higher. There is an old homestead there. All the buildings and structures have fallen in except the old windmill and well. Im planning on cleaning (if it's structurally sound) the old well and building a ferrocrete tank (cistern?) for the windmill to pump into and let gravity feed water into the house (may have to supplement with a pump if pressure isn't enough). I’m hoping it would deliver enough to at least flush toilets and keep the faucets running if power wasn't available. Showers might not be feasible though without pressure supplement.

A power line runs along the edge of the property which means I'm going to have to bury electricity for about 150 feet. I'll probably work on some alternate energy project later down the road, but that is not within my price range right now. I've planned to use natural lighting as much as possible and plan for situations where electricity isn't available by removing as much reliance on it from the initial design (like the water situation). I even have an experiment running using the Jean Pain method for heating the water and probably the house itself without power if that's even needed. If it works out this winter, that may change the way my design goes from here on out.

Maybe I'm barking up the wrong tree, but I look at it like this: if I live in it ten years and it costs me $10,000, that's about $83.00 a month. Compound what that saves in heating and cooling costs, I figure about $25.00 a month in the 3 coldest winter months and $35.00 in the 2 hottest summer months that’s $145 a year or about $1450 over the 10 year duration, making it a $8550 total investment. If nothing else it saves me enough to build something different.

Mike has lived in his for over 30. If I can make it to 30 years for $10K that’s about $28.00 a month, and saving $4350.00 in energy costs (that’s at today’s prices).If it lasts 50 years, it’s free. (Wishful thinking, I know). Oh, and I’m not in an area where building permits are required, so I can be a bit more free with my design than I would otherwise.

Anyone have the videos that Mike Oehler offers? I’m interested to learn more, just not sure if it’s $95.00 worth of interest (what he charges for his videos). I may order them anyway, as this design seems to be getting more solid every day and as I discuss this more the problems and questions seem to be resolving themselves. The more I work with the idea, the more feasible it seems. If anyone has bought them and scrapped the plan, we might talk...

So that’s my plan in a nutshell. Lots of labor involved in this project. But I have a lot more time than I have money.

So here’s the question: Has anyone here tried this particular building principle to see if its sound? I just want some real world facts. If anyone has any links or resources that I should look at I would appreciate it as well.

As a side note I have thought about termites. I'm working ways around it but if anyone has any ideas I'm all ears. I know they're pretty diligent little critters, so quite a bit of thought needs to go into that. One person suggested plastic underneath but that would be hard to do I think.

I was pointed to a forum where one owner/builder is constructing his own. It provides a lot of pictures and gives a more visual idea of what is possible. There is so much natural light in several of the pics that it’s difficult to remember that it’s an underground house. The builder is a mod at the www.countryplans.com forum. Thread link Here.

a pity you dont live here in australia mate, i could have helped you out and in turn you could have helped me. you have a great idea of which i have had the same idea for years. take care ok regards steve

Nicholas Covey wrote:
I post this not to stifle anyone or close the thread, but to just give an update of sorts as some have commented that they wondered what had happened to me and my project. I hope that at the very least we have all learned a lot in this and that people will continue to post on it and evolve the idea. I still believe that in the right application that this design is far superior to many others, and I wish desperately that I could implement it myself. Right now that doesn't seem so likely.

paul wheaton wrote:It does seem that with PSP there is zero wood to soil contact.  Are you thinking of something different from that?

BTW:  here is a pic from krameterhof.at of the kind of oehler-like thing that sepp builds in a day:

R wannabe wrote:He does in a day what would take a month by hand. This is one of the areas that hiring a little help might be smart money. Yes it may cost a grand to get that machine for a day, but what else could YOU do with that month on other projects.

Dan alan wrote: Infact, I'd be willing to make a video explaining the whole process of plastic welding if anyone needs me to.

Chris Kott wrote:Even with the limitation of a 4-foot roll, wouldn't it be sufficient to lay the barrier material down from the bottom of the roof slope up, overlapping in the same manner as asphalt shingles, such that any water not wicked away by the soil will continue downhill, uninterrupted?
-CK

paul wheaton wrote:The trick is that once steel starts to rust, it can keep going without further water.  Now, I could be wrong about this, but I think I'm not. 

So!  With that wee bit of rust you already have, it will just keep going and going. 

Chadwick Holmes wrote:Soil wieght on a square is the deal, square is not the first choice for wieght load retention...

Dustin Krieger wrote:Hey everyone,
Rather than go it alone and end up buried alive, I seek advice on how to successfully build a long-term durable underground house in Tennessee. Please reach out with advice and thoughts and any DIY guides would be great!