Our Underground House in Texas - Planning Stage, with Pics!

Hello all!
We have been reading here for a while and thoroughly enjoyed and benefited from all the knowledge and experience on the forum. We are a family of four living in north central Texas, and feel like it is time to set to work on our low impact, high efficiency home.

We have been researching underground/earth sheltered construction upwards of a year, and are leaning heavily towards a variation of Mr. Wheaton's Wofati house. My wife and I are by no means experts on earth sheltered building, so we would like to ask for a lot of input from those of you who have experience here. I have some construction experience and am relatively handy in wood and metalworking, but building a house to properly shed water with a structure made of wild oak from the woodlot will be brand new to me!

So, the purpose of this post is to get input from folks here on my current (shadow of a) plan, 'cause I'm not too proud to admit I need a lot of help! I've attached some photos my sweet wife took of me standing in our prospective site (for scale, I'm six feet tall). It's a dry pond excavated into a gradual hill with the dirt removed use to build the downhill dam (which is toward the north, which is behind me in most of the pictures). It poses a couple of challenges that I think can be overcome, but I need folks with more brains than me to weigh in... So, please see attachments!

First and second pictures:

As you can see, it's relatively spacious, about 65'x40', depending on how you measure it. Excavating further is not too big a deal, and I figure will have to happen since it's a typical teardrop/ice cream cone shape. We're aiming for something just over 2000 sq. ft. At this point, my plan is to have the front door at the north (where the dam is) under a sizable round gable with plenty of windows, and the back door/uphill patio at the south, where you see a depression/runoff channel already exists. This depression is where my wife is taking the second picture from.

Third picture, next post:

The side toward the west (shown here) is a slight downhill from the plot, and shouldn't pose any problems. I'd like to bring in plenty of light with dormers or a medium gable.

Fourth picture, next post:

Behind me is the east side, and one of two potential issues I see. It is a gradual uphill from the plot, with minor runoff potential. Problem is, this is in addition to the uphill southerly slope, which bears significant (but not insurmountable) runoff potential. At this point, my best solution is to extend the uphill patio all the way from the southwest corner around the east side of the house to the very northeast corner, effectively making half the circumference of the house an uphill patio. Not bad, in my thought, since when we were planning a conventional house my wife asked me very sweetly for a BIG wraparound porch. I've just never seen it done this way, so I'm trepidatious.

The second issue I see is the south end. As I said, the pond is teardrop shaped, and comes to a sharp point that is somewhat deeply recessed (approx. 4 feet is my guess sitting here) beneath the pasture to the south. Problem is, this point is maybe 30 feet south of where I expect the south face of the house to be. Now, here is where I get pretty lost, no doubt... I have thought of backfilling it and making a conventional uphill patio closer to the house. I have also thought of trying to incorporate the entire area into the uphill patio, which would be doable, while requiring some clever runoff control (large culvert running under the house or east patio, maybe?) and making the patio QUITE large on the south end. I have even though of excavating a deep little fish pond in it and dealing with excess runoff via overflow pipes similar to the previous idea. There are several other ponds on the land where similar systems work like a charm.

I have a few (more brief) questions about my construction plans, and will post drawings later, but for now I'd mainly ask for input on this possible site. Is the groundwater workable? There are a couple of single incline grades available that I can use if I have to, so fire away. But we really like this spot for a lot of other reasons, so it'd be nice to make it work. I'm open to suggestions!

Aaron, for the fam!



P.S.: Once we break ground, I plan to document every step of the way, mistakes and successes, here on the board, and hopefully a blog, just in case someone else can learn from my experience. I'd like to give back as much as I can, since I know I'm asking a lot of input here. Thanks for reading!

If it matters, this thread is cross posted at: http://countryplans.com/smf/index.php?topic=10898.0

Here's the other two pictures.

Obligatory silliness.

That looks like a dry creek bed that might run during heavy rains. Also looks like it could be an area where water might pond during rainy times.... I think that it might be a good idea to get an expert to give you an expert opinion if you can build there and advise you on the drainage.

Pond bottom may not make a great foundation unless you are willing to remove the thick organic layer (keep it). you need to find out how far down something stable is.

Ronie,
It's not really a creek bed, right behind the photographer is a 5 foot rise to the rest of the pasture. It shouldn't run any more than any other 20'x20' hole, but I'm obviously (see post) still considering my options.  I mean, really what it comes down to is that my site (hole) is 20 foot bigger on the uphill side than I want to build. So, if I just built my house all the way up to the excavation, I guess that would solve my problem...

Unfortunately, we run awful short of earth sheltered house building experts where I'm at, thus I'm here. 

Len,
Yeah, this "pond" doesn't really hold water long enough to develop much of an organic layer... Hard red clay is about an INCH down.

Please feel free to bring any more suggestions or questions. I want to make sure I know what I'm doing before I start. When I get on tomorrow, I'll give some more details on actual construction plan.

Thanks!

Aaron

Have you thought about building on the 5 foot rise?

Are you thinking of building ground level then mounding dirt up around the structure?

Ronie,
This is more of the "built into the slope" idea. As far as building up on the rise goes, it defeats some of the purpose in my mind. It's been about 105 degrees all day, every day, here for the last few weeks. I would like to have the house low, out of the path of the strong, hot winds that blow accross that feild, and with plenty of earth surrounding for maximum passive cooling. The pond bottom is just about perfect, offering a low lying spot that is already half excavated.

I've come up with a few (pitiful) drawings that may help illustrate what I'm talking about. This is an aerial photo of the plot taken at one of the few times the depression has ever had significant water in it. I've tried as best as I can to illustrate the runoff pattern as well.




Existing slopes and drainage patterns.


My current idea of the house footprint, showing roof peaks and dips, and rainwater flow. Any thoughts?

Aaron

Maybe a good place for an earthship. However, I'm a little prejudice. Since you're in Texas why don't you contact David South in Italy TX (monolithic domes). They have the dome system. They would be more than happy to discuss what you're trying to achieve.  I guess it all depends on what you're looking for and your resources (DIY, green, Stick built, underground, bermed, etc.).

I reckon you've been influenced by Mike Oehler's underground house book. It's a great book, but I believe he built all of his houses in the hilly and well drained forests of N California which has a remarkable moderate climate. There is nowhere in Texas like NoCal. I'm from Texas, so I know.

there's a few things that I think might shift your priorities.

-anywhere in Texas, a reasonably well insulated house with well designed south facing glazing and overhangs should be able to supply 80-100% of it's heating needs passively (even in the panhandle).
-On the other hand, in Texas keeping your house cool will be the major concern 8-10 months of the year.
-shading, ventilation and thermal mass are your best allies for cooling.
-building underground will give you tons of thermal mass, but won't help with shading and is likely to hurt ventilation.

the overwhelming influence on the low impact of your structure will be the embodied energy used in it's construction and the shape of building (including the size and location of your windows). underground construction will be very energy intensive, and if you allow a hole in the ground to dictate the shape of your house, the sun will use all it's strength to remind you how much more important it is.

Just for starters, (assuming north is up in the aerial photos) you have your main windows in the dormers to the NW corner of the house. This is the corner that receives the most solar radiation in the heat of the summer. you'll also notice that the plan of your house has the longest walls on the east and west sides, while the existing building (is that a trailer?) in the picture has tiny little E-W walls and rather long N-S walls. This building would probably require less cooling than yours even if yours is underground. The sun in summer months spends hours low in the sky to east and to the west, and in Winter the sun is low on the south side. Also just so you know there will be know more important decision you make than what material you cover your roof in. I know of houses in Central Texas that have switched from comp shingle to metal roofing and gone from running the AC 9 months of the year to running it 1 month. At that rate, the metal roof will pay for itself in about 3 years.

I would start by getting a book on passive solar design. almost anything basic will do. It it's self build (I get that impression from your post) I would keep the rooflines and footprint as simple as possible. (ie dormers can be hard to keep waterproof) Look at traditional southern building types; dog trot, wraparound porches etc.
I would also suggest a simpler above ground technique like straw-bale. (for one thing there are dozens of people between TX and NM that are global experts in SB or adobe and most of them do courses. Underground building not so much.)

You might think I'm poo-pooing your idea, but I'm not really I just think you've prioritised the wrong things. It takes tons of experience with construction to know what those priorities are. I've just given you a ton of free design advice, but there's so much more to say!!

I've just spewed all this out, so I hope it makes some kind of sense.
Also I am an architect with a background in sustainability, so I'm not some idiot rambling on the internet (at least I think not!?)

I'd be very concerned about building a house in a drainage or low spot in Texas.  These kinds of low spots can become raging torrents during heavy rains.  I certainly wouldn't consider building there until you've observed the area during a flood.

IN MY YEARS IN TEXAS THE ONE ABIDING TRUTH NEVER FAILS TRUISM OF NATURE ....IF THERE IS A LOW SPOT IT WILL EVENTUALLY FILL WITH AN ENORMOUS AMOUNT OF WATER. I NEVER GAMBLE BUT I'D BUILD A RETIREMENT PLAN BASED ON A BET THAT PEOPLE BUILDING IN LOW SPOTS WILL FLOOD EVENTUALLY IN TEXAS. I LIVE AT ABOUT 1300 FT ON A HILL IN CENTRAL TEXAS WHERE THE EASIEST PLANTS TO GROW ARE DESERT ADAPTED PLANTS AND TWICE IN 18 YEARS I HAVE SEEN 6 INCHES OF WATER FLOW ON EACH SIDE OF MY HOME AND SPOTS THAT ARE BONE DRY GET 50 FT DEEP IN WATER BECAUSE OF THE SHEER VOLUME OF WATER THAT CAN GET DUMPED ON TEXAS. MY BROTHER ONCE TOLD ME A TEXAS STORM IS JUST TEXAS TELLING FOLKS FOLKS WHERE THEY DECIDED TO LIVE. A LOW SPOT IN TEXAS IS A LAKE BY ANY OTHER NAME AND THE RIGHT TROPICAL STORM CAN MAKE ARID PLACES LOOK ALMOST BIBLICAL IN FLOOD CONDITIONS ....BUILD ON HIGH GROUND. WE HAD AN UNDERGROUND HOME THAT FLOODED SIMPLY FROM HYDRAULIC PRESSURE OF GROUND WATER. I SERIOUSLY HOPE YOU DON'T BUILD THERE

Richard Allen wrote:IN MY YEARS IN TEXAS THE ONE ABIDING TRUTH NEVER FAILS TRUISM OF NATURE ....IF THERE IS A LOW SPOT IT WILL EVENTUALLY FILL WITH AN ENORMOUS AMOUNT OF WATER. I NEVER GAMBLE BUT I'D BUILD A RETIREMENT PLAN BASED ON A BET THAT PEOPLE BUILDING IN LOW SPOTS WILL FLOOD EVENTUALLY IN TEXAS. I LIVE AT ABOUT 1300 FT ON A HILL IN CENTRAL TEXAS WHERE THE EASIEST PLANTS TO GROW ARE DESERT ADAPTED PLANTS AND TWICE IN 18 YEARS I HAVE SEEN 6 INCHES OF WATER FLOW ON EACH SIDE OF MY HOME AND SPOTS THAT ARE BONE DRY GET 50 FT DEEP IN WATER BECAUSE OF THE SHEER VOLUME OF WATER THAT CAN GET DUMPED ON TEXAS. MY BROTHER ONCE TOLD ME A TEXAS STORM IS JUST TEXAS TELLING FOLKS FOLKS WHERE THEY DECIDED TO LIVE. A LOW SPOT IN TEXAS IS A LAKE BY ANY OTHER NAME AND THE RIGHT TROPICAL STORM CAN MAKE ARID PLACES LOOK ALMOST BIBLICAL IN FLOOD CONDITIONS ....BUILD ON HIGH GROUND. WE HAD AN UNDERGROUND HOME THAT FLOODED SIMPLY FROM HYDRAULIC PRESSURE OF GROUND WATER. I SERIOUSLY HOPE YOU DON'T BUILD THERE

uh.... listen to this guy ^^^^^^^

Howdy Benjamin welcome to permies.

I know this thread is old . . .

Given I have friends in Texas who deal with season flooding I'm voting with those who say don't build in the swale. (someone want to tell me why 'swale' isn't in the dictionary here?)

Consider this. Move the setting of the house to the hilltop. Provide good insulation and adequate overhang. Use ground tubes for thermal heating/cooling. With the natural rise the buried tubes would do a very good job of cooling and providing fresh air.

I remember reading about a house in Texas that had PAHS. The site had really good photos and diagrams. Here's the original paper on PAHS by John Hait http://www.earthsongfarm.com/PAHS.html.