How deep could I set my house foundations (basement)

General Questions
#1

Say I’m a crazy rich bastard and I want to have a one story high house, with 30 basement levels.

Is there any laws (Canadian, US or other) that would prevent me from having a house that goes really deep?
-Considering the house is situated in a suburb somewhere where there are no subways or other important stuff (i.e. drinking water, prehistoric caves…etc) going under.

Also, is there any structural problems that would make my dream impossible?

and finally what would happen to my house if there was an earthquake?

#2

AFAIK the only laws that would affect your building a Dr. Evil Secret Underground Lair complete with underground parking for your Big Boy space shuttle would be the ones that govern mineral rights–sometimes people discover to their dismay that other people own the mineral rights to the land under their house.

However, a truly competent megalomaniac would have his lawyers check that out before he started digging, so it’s probably a non-issue.

So, other than the physical limitations caused by hitting bedrock and/or ground water, and bearing in mind the possible location of a subway right where the Big Boy is going to sit, I don’t see why you couldn’t dig down as far as you wanted.

As to how the Secret Underground Lair would hold up in a 7.5 earthquake, I have no idea, sorry.

#3

You`re going to have constant pressure on the basement walls from the surrounding earth and the water table. You will have to build the walls extra thick as you go deeper. The other problem is shoring up the hole as it is being dug. Digging a hole that deep is half the battle.
If your structure is mostly below ground its relative movement to the earth in an earthquake is minimal.

#4

I don’t know if this helps but I live in CT and I have a semi-two-level basement. We have a radon dtector down there on the lower level because we are situated on ledge rock. The second basement has 11 foot tall ceilings because the people who owned the home before us had a large wine cellar. When my wife and I bought the place we asked if we could keep the cedar racks, or at least the ones on the wall. They ended up taking the free standing racks and we got the wall mounted ones.

The second basement is kind of cool, because it is so far under ground. Our house is multi-levels. One part of the basement s exposed, and you can walk right into it from a sliding door, but walk up the hill a bit and you’d be level with the first floor ofthe house. In all the first floor is 25 feet from the floor of the second basement.

Why would you want so many subdivisions below your home? Do you live in Tornado ally or anything like that? Bosnia?

#5

I’m getting an image of an inverted pyramid structure. :slight_smile:

Anyway, how do you intend to clear away all that dirt? In the country, no problem: You either sell it as fill or create a small hill by your domicile. Hauling dirt around in the country isn’t a problem unless you need to preserve some grass. But how would it work if your haulers are limited to your yard and whatever suburban roads give access to it?

#6

Permits, permits, permits. Even in the country there are limitations on what you can do with the fill. In the U.S. In Colorado, it’s done on a county by county basis. We have what is called a ‘grading and excavating’ permit.

#7

Virtually all building codes do not allow home construction below the water table. Depending on where you live, this could be at ground level (think Louisiana bayou) or hundreds of feet (mountain desert). Your local county or city building department will have maps showing the water table level where you live. Why not buy an old missle silo? They are 100 to 150 feed deep and have all the expensive ventilation equipment in place. Here in the Seattle area we had the epic battle of Bill Gates vs. the Medina (small Seattle suburb) building department during the construction of Gates new $25 million dollar home. He wanted to cut the side off a hill overlooking Lake Washington to build his new home. The city would not let him so he had to settle for a 40,000 square foot house on the side of a hill instead of in the hill.

#8

DrLiver, you would have to call your local building dept & ask them.

#9

handy: Believe me or not, I’m not a real crazy rich bastard…well, at least I’m not rich…so I don’t think I’ll start the construction anytime soon, that was just a question to satisfy my curiosity (that’s why I asked the SDMB instead of going through the trouble of calling people)
And I have two questions: would the extra thick walls need to be in the sens of a inverted pyramid or just a little bit thicker would be OK…and also, what’s table water? is that the underground water from which the wells take their water?

#10

Yes (a little thicker according to the type of ground) and, Yes the level at which the water saturates the ground.

#11

[ul]:smiley: [sup]He has a Saddam complex.[/sup][/ul]

#12

I know that in Britain any building designed for living in should have at least one window - you technically can’t live in your basement unless it has even a small amount of natural light coming into it. So do you want it as a funky underground boudoir or for keeping an enormous weapons stash and as a nuclear fallout kingdom? I have to say I have always fantasised about having a huge underground complex from which I could plot the eventual domination of the world.

#13

Germans are wierd that way, too. Your basement must have windows. They apply that to workplaces, too. Every place that people work has got to have natural light available. Never mind the reflections on the monitor and all that good shit. Gotta have natural light. People here think I’m weird because I like to close the shutters and turn on the room lights when I’m on the computer watching TV.

#14

computer OR wahtching TV

Jeez.

#15

DrLiver, the thing is you could hit bedrock or just rock. Getting through that is not very practical.

#16

Dynamite…

#17

As a structural engineer, let me say, if you have the money, honey, I’ve got the building for you. We can go as deep as you like. Depending on the soil, the walls normally get thicker for a while and they reach steady state. Building permits will not be an issue. If you have the money to build it, I assume you we can get approval. Where are you located? This will be much cheaper in some areas than others. Hard rock is good, clay is ok, sand/karstic limestone/muck is bad.

#18

Ever since I saw a tv special about shelters that featured a story about this guy in Florida I think, that built this huge shelter under his house all bby himself, I’ve wanted one. I thought that was the coolest thing when I saw it. I can’t even imagine knowing where to start something like that.

#19

Yes, but there’s always the nagging thought in the back of your mind that somewhere there was once and might still be a multi-megaton thermonuclear bomb aimed at your house… :eek:

#20

can you REALLY buy missile silos?

how much would that cost?

If I buy one, should I fear residual radiation or other potential health problems?

how about in a deserted island? Do i have more chance of hitting underground water on an island? It seems logical to say yes, but on the other hand if its above water and didn’t get melted away by the sea, it must be somewhat dry under too…but then again, maybe i’m just crazy…