Phalynx's attempt and a small underground shelter.

[phalynx]

I just started construction on a small underground shelter (just for the heck of it).  Yes, you can call me Glenn Jr.  Glenn and I have been PM'ing for a few days now and I thought it would be better to just go ahead and post a topic.  That way I can upload pictures and everyone can make fun of me.     Anyway, I don't have a lot of slope on my property so I picked the best place and with the tractor started to dig.  So far, I have gotten about 6' down and it's still sand... very interesting.  Here is a pic.



Anyway, It will start as a shelter, and grow into storage, and even into a small studio for me at some point (if I can do what Glenn does so well)

[glenn kangiser]

Well --- that takes care of the pix request I made in the PM.

Phalynx, that is great for a flatlander.

Keep the pix coming.


Hmmm hmm.  Make fun of you.... Moi?

Building underground is only as weird as you want it to be.  It keeps the riff-raff away. ....

Actually, when you are successful, you will find people coming to visit often just to see it.

This is going to be fun....

Now I'm not the only crazy one on the forum...

[phalynx]

It looks like a beautiful sandy beach doesn't it?  It's getting hard to find places to put the dirt where it isn't a long way away.  Behind the camera in the pic is the exact inverse of the hole.  I had to start dumping it on the side too.  I have to leave an escape for the tractor in the whole thing too.  I guess if I make the dig about 100' longer I could actually slope the water away from the bottom..  But then again, what's rain look like anyway?  I haven't seen it in years.

[phalynx]

Actually, when you are successful, you will find people coming to visit often just to see it.

Wait a minute........  It would be an underground structure.... Wouldn't they be "dropping in"?

[glenn kangiser]

Only thing missing is the water and babes in bikinis.


So which way is down hill?  A bit hard to tell from the pix.

Have you decided on a first stage size?

Actually, when you are successful, you will find people coming to visit often just to see it.

Wait a minute........  It would be an underground structure.... Wouldn't they be "dropping in"?

I'll show you some ways to get light in without people falling into skylights.   No people droppings that way.   

[phalynx]

The camera is looking up hill, if you can call it that.  The hole is about 11' wide right now.  Although it would be easy to widen it.  I figure with 11', I can make the place 8x16 to start.  8x8 just seems too small.

Here are the babes,,, my babes at least.  They won't be wearing bikinis though... not for another, say, 20 years?  That sounds about right.. 

[glenn kangiser]

Well. them there are some mighty fine lookin' babes anyway.

OK - so you will flatten it out for a distance of 16' plus about 2 feet coming this direction to get a flat work area for the floor then I guess, eh?

Looking good.

[phalynx]

I'll show you some ways to get light in without people falling into skylights.   No people droppings that way.   

Ok, I just can't resist......  I am not building an underground outhouse.. There should be no "people droppings".

[glenn kangiser]

No underground outhouse? hmm Where will you go?

[Dog]

Oh I can tell this thread is going to be good! 

What kind of studio are you building Phalynx if you don't mind me asking?

[phalynx]

Well, one of my first loves it making music, 2nd is shooting/editing video.  The 2 together makes for a fun little studio.  This structure, if Glenn coaches well   will be expanding to form several things including a shelter, root cellar type, SHTF bunker, etc..

[phalynx]

No underground outhouse? hmm Where will you go?

I'll have to think about that.  I am not one who's going to sit on a hole in the ground.  Plus, waste (come on, you know what I mean) rolls down hill.  I have dug into the side of mine....  Where it will go, I dunno?  I suppose I could keep digging and create a basement of some sorts... but you know how that works.  When you are done with the house, you renovate the basement and my wife will certainly want a bathroom in there...  Then I'd have to dig deeper.

So where will I go?,,,,,, hummm, with enough time, China?

[glenn kangiser]

Alternatives -- the outside outhouse....

My first one had no walls here at the underground complex. 

That was cool until I mooned Sassy and in about thirty seconds the old man who delivered my building plans for my life on the outside walked up behind her.  He retired shortly thereafter. ( In real life, I am a prostitute.  I sell my body for money.... to any company who will pay me enough to install their steel - weld - contract - etc....

We have a normal septic system here now though.

[phalynx]

I am sure that was the highlight of his day. I am sure you were the "butt" of many jokes as well.  He started the day as a building plan deliverer and ended up an astronomer.  He was viewing Uranus.  Ok, maybe that was bad.

I got started early this morning digging.  I have dug down about 11' right now.  I am surprised the sides haven't fallen.  Of course, now that I did this, it is now raining.  I guess I will find out if I started an underground shelter or a pond...

[glenn kangiser]

You forgot the part about searching for Klingons.

11'  are you going to stop?

Watch the sides - no kids near them.  About 150 lbs per cubic foot so a collapse will really squash something - maybe even a tractor.

[phalynx]

Right now I am interested in seeing if there is anything other than sand.  The kids are no longer allowed in there for safety.  I am also going to start tapering the sides for good measure.  Or, I am going to get my fishing pole.

[glenn kangiser]

Possibly of use here when we think about footings.  I don't like to bury the poles - I had three with problems - the only 3 I buried.  You don't want preservatives in your living space though so a footing with a pin is what I went to.

from  here

http://books.google.com/books?id=1rxKLpO0kyIC&pg=PA130&lpg=PA130&dq=weught+bearing+capacity+sand+square+foot&source=bl&ots=5Hpg3yUFBa&sig=KjElCFuuzJVYyY96D0EOhIYnbXU&hl=en&ei=42UPSqWeB4rwswOQwrGSAw&sa=X&oi=book_result&ct=result&resnum=7#PPA131,M1

[phalynx]

We got 1.5" of rain in a very short period of time.  I went and checked the hole and oddly enough, there wasn't a single puddle in it.  The water had drained away into the sand...

[glenn kangiser]

Looks like it may handle it's own drainage problems.

[phalynx]

Yeah, that is a little interesting actually.  I would have expected there to be some puddling.  But there was none...  Where did it go, and if it did go, is this a bad thing for other things?

[glenn kangiser]

No problem as I see it.  Sand is around 25 to 30 % or so porous so it just headed down to the water table.  You could try a posthole digger to see what lies below for a little ways.  If no clay layers nearby  below, you likely will have no drainage problem.

[Dog]

Your house came out beautiful! Congratulations!
Building underground now...how exciting! You'll have a true man cave 

[phalynx]

I like to keep busy.

Ok Glenn,,, aka. "Master", I have a hole... what is next?

[glenn kangiser]

I'm assuming that is not a personal problem and we are talking about the shelter?

So - we want to keep that hole open now by putting a cabin in it that is strong enough to keep it that way.

The appx 12 1/2 inch dia girders (for 8' span) go on top of the posts so if the posts are kept above floor level with a footing under them then the shortest could be  around 6 feet minimum and getting longer toward the higher sloped side.  That would give you about 7' clear on the low side under the beams at the lowest end.  Keep in mind that the post centers are 8" so you need extra long girders - If adding an uphill patio as suggested for light and a second way out, I would suggest about 2'6" to 4'6"  extra long.  It would cantilever over the top of the tallest posts for an extra beam or two.

Posts need to be around 8" diameter and beams around 7 1/2 " dia. on 24" centers.   I would not worry so much about the species but reduce the loading to 18" or less - 12" is pretty good.  Posts in this design would match mine in multiples of 8' square spacing.

Your desired roof pitch would give you the length of the high side posts.  The girders would run from the low post to the high post and the beams horizontally across them.  You need a 16" ship auger type drill in the size you want for rebar pins - I used 1/2 and or 5/8, and I liked to set about a 3/4 pin in the concrete footing vertically then drill a 1" hole in the post to set it over the 3/4 pin. 

Here the ground was solid enough that I didn't need a footing.  In your case with the sand I would suggest about a 24" x 24" minimum  concrete footing at least 8" deep with a short - maybe 4" min high by 8"round or square extension up to set your post on. 

What do you find as the soil type there - dry - hard pack - fine - ?  I was just assuming from what you mentioned earlier.  Larger footing size if soil does not seem like it will support the weight.  This structure is pretty forgiving in that you will be using trees and not expecting things to be more plumb - straight and square than the best you can do with the fine "rustic" standard.

I am giving you suggestions of what worked for me but ultimately it is up to you to decide on the safety of any given suggestion.  My soil conditions were such that a tractor would not move a steel ground pin - you have sand.  Still doable with proper modification.  Sand is just small particles of rock.   Not as supportive though.

[glenn kangiser]

I mentioned it before, but with this.deep an excavation in sandy soil the sides can become unstable and slide in without warning.  I know you said you were going to slope them, but be careful.  Sand is about 3000 lbs per cu yd.  Figure it could come in from about a 45 from the bottom.