Archived Posts » 59,859,448
Building an underground shelter. I have a question or two.
4/18/2012 11:42:24 AM
I will be pouring a 12'x24' concrete slab behind my house where I currently have a very low wooden deck. I am considering installing a 8'x8'x8' in ground metal shelter directly under the slab. I have a friend who is a welder, and he has offered to weld everything for me, but I have a few concerns. The sheet steel I have found is sold in 4'x8' sections. I am considering using 1/8" steel for the walls and floor, and 1/4" steel for the roof and door. In theory, I can piece the 4'x8' sections of steel together to make a perfect cube, but I am pretty certain that won't work without quite a bit of bracing. Do you guys have any ideas, links, or experience regarding what I am considering doing?? I AM NOT going to build this thing and put my family in it unless I know for sure that it is safe. I plan to paint the inside and outside of the shelter with something water proof as well. Any insight you guys can give me will be greatly appreciated. Thanks in advance.
4/18/2012 1:22:07 PM
A sheet metal room surrounded by dirt? No good.
Think about making it out of reinforced concrete.
Think about making it out of reinforced concrete.
4/18/2012 1:26:21 PM
Originally Posted By 44Regular:
A sheet metal room surrounded by dirt? No good.
Think about making it out of reinforced concrete.
A sheet metal room surrounded by dirt? No good.
Think about making it out of reinforced concrete.
I am considering the concrete, but I see lots of buried steel shelters. From my understand, the shelters that are buried inside of a garage are made of 1/8" steel on the walls and 1/4" steel. I understand that it becomes a different animal when you increase the size of the shelter, but I think this could be solved with bracing.
4/18/2012 1:34:10 PM
I may have misunderstood.
Yes it can be done with metal. Huge metal tanks sit in the ground for years with no problem. But what are you protecting your family from? Will sheet metal with a dirt cover do what you want? The cost of designing all the bracing, fabrication, waterproofing, backfilling, etc. might be more expensive than cast in place concrete and it might not be as durable or offer as much protection.
It's hard to beat concrete underground.
Yes it can be done with metal. Huge metal tanks sit in the ground for years with no problem. But what are you protecting your family from? Will sheet metal with a dirt cover do what you want? The cost of designing all the bracing, fabrication, waterproofing, backfilling, etc. might be more expensive than cast in place concrete and it might not be as durable or offer as much protection.
It's hard to beat concrete underground.
4/18/2012 2:03:03 PM
Exactly.
4/18/2012 2:41:56 PM
Originally Posted By sarge38624:
Do you guys have any ideas, links, or experience regarding what I am considering doing?? I AM NOT going to build this thing and put my family in it unless I know for sure that it is safe.
Do you guys have any ideas, links, or experience regarding what I am considering doing?? I AM NOT going to build this thing and put my family in it unless I know for sure that it is safe.
for reference, see how CEV's are constructed and installed:
http://www.google.com/search?q=controlled+environment+vault
e.g.
http://rockwayprecast.com/product/index/Controlled+Environment+Vaults+%28CEV%29/5/
ar-jedi
4/18/2012 7:43:43 PM
Pour it all at once. Dig the walls of the shelter from above and tie it all together. After the concrete cures, dig out your room and pour a floor in it.
4/18/2012 11:09:01 PM
Just remember that soil backfill when saturated is subjecting flat sidewalls to enormous loads, unlike that of dry soil, and the reason for reinforced concrete.
4/19/2012 9:53:43 AM
if your water table is low enough to not have to worry about putting in a sump then pouring a concrete
shelter is prolly best.
otherwise if you want to go steel, look for underground tanks (gas, water, ect)
they are waterproof and made to bury. just have to get your buddy to fab up a hatch.
this one is 23 feet long by 8foot diameter
shelter is prolly best.
otherwise if you want to go steel, look for underground tanks (gas, water, ect)
they are waterproof and made to bury. just have to get your buddy to fab up a hatch.
this one is 23 feet long by 8foot diameter
4/19/2012 10:57:47 AM
On the tv show "Doomsday Bunkers" they make bunkers out of steel walls but it has a lot of exterior bracing on it. Here is their website.
http://www.deepearthbunker.com/
http://www.deepearthbunker.com/
4/19/2012 12:44:49 PM
A high water table is trouble for a buried tank full of air. It's trouble for a concrete vault if there isn't enough mass or enough pumping.
4/20/2012 1:21:49 AM
We've been discussing a somewhat larger room. We'd considered a skeleton of concrete grating with the walls poured around it. I've seen some pretty gnarly buckling from wet earth pressing in on structures, and I'd be concerned with any metal that wasn't hella reinforced and configured for the particular stresses involved.
4/20/2012 8:03:06 AM
dude, concrete block is cheap, couple grand, use normal basement waterproofing and insulation
4/20/2012 3:41:47 PM
Originally Posted By 44Regular:
A high water table is trouble for a buried tank full of air. It's trouble for a concrete vault if there isn't enough mass or enough pumping.
A high water table is trouble for a buried tank full of air. It's trouble for a concrete vault if there isn't enough mass or enough pumping.
you anchor it , then you dont have to worry about it floating out
4/20/2012 7:34:11 PM
I'm thinking steel culvert. Look at Utah Shelter Systems for ideas. I am also considering Cargo container with mucho bracing inside. I could build bunks for beds and divide it into rooms also. That would be functional and not so intrusive.
4/21/2012 12:02:40 AM
Originally Posted By J75player:
you anchor it , then you dont have to worry about it floating out
Originally Posted By 44Regular:
A high water table is trouble for a buried tank full of air. It's trouble for a concrete vault if there isn't enough mass or enough pumping.
A high water table is trouble for a buried tank full of air. It's trouble for a concrete vault if there isn't enough mass or enough pumping.
you anchor it , then you dont have to worry about it floating out
Yep.
If you see it starting to get ready to pop out start pumping water down into it.
Be sure to stand clear in case it pops out before you fill it with enough water and sucks you back into the hole.
4/21/2012 12:05:31 AM
Originally Posted By snakeshooter1:
I'm thinking steel culvert. Look at Utah Shelter Systems for ideas. I am also considering Cargo container with mucho bracing inside. I could build bunks for beds and divide it into rooms also. That would be functional and not so intrusive.
I'm thinking steel culvert. Look at Utah Shelter Systems for ideas. I am also considering Cargo container with mucho bracing inside. I could build bunks for beds and divide it into rooms also. That would be functional and not so intrusive.
We're sitting/living in a container right now. I have no idea how we could move around if it had mucho bracing inside.
Think abt how little room there is in a 'tainer.
Also, do you know the floor is just thick plywood screwed to cross braces?
4/21/2012 3:00:43 AM
Originally Posted By J75player:
you anchor it , then you dont have to worry about it floating out
Originally Posted By 44Regular:
A high water table is trouble for a buried tank full of air. It's trouble for a concrete vault if there isn't enough mass or enough pumping.
A high water table is trouble for a buried tank full of air. It's trouble for a concrete vault if there isn't enough mass or enough pumping.
you anchor it , then you dont have to worry about it floating out
The point I was trying to make is that a tank is not going to work without a lot of concrete holding it down, so you might as well just go with concrete. Unless you know of some other material to anchor a tank with.
4/21/2012 4:49:31 AM
Originally Posted By 44Regular:
The point I was trying to make is that a tank is not going to work without a lot of concrete holding it down, so you might as well just go with concrete. Unless you know of some other material to anchor a tank with.
Originally Posted By J75player:
you anchor it , then you dont have to worry about it floating out
Originally Posted By 44Regular:
A high water table is trouble for a buried tank full of air. It's trouble for a concrete vault if there isn't enough mass or enough pumping.
A high water table is trouble for a buried tank full of air. It's trouble for a concrete vault if there isn't enough mass or enough pumping.
you anchor it , then you dont have to worry about it floating out
The point I was trying to make is that a tank is not going to work without a lot of concrete holding it down, so you might as well just go with concrete. Unless you know of some other material to anchor a tank with.
no your right, you anchor it with concrete. but unlike building a concrete shelter, the steel tank wont leak.
you can keep a concrete shelter dry, but it generaly takes alot of work and some luck with a high water table.
plus, pouring some concrete anchors is alot easier then pouring floor/walls/roof of a shelter.
4/21/2012 12:13:37 PM
Originally Posted By J75player:
no your right, you anchor it with concrete. but unlike building a concrete shelter, the steel tank wont leak.
you can keep a concrete shelter dry, but it generaly takes alot of work and some luck with a high water table.
plus, pouring some concrete anchors is alot easier then pouring floor/walls/roof of a shelter.
Originally Posted By 44Regular:
The point I was trying to make is that a tank is not going to work without a lot of concrete holding it down, so you might as well just go with concrete. Unless you know of some other material to anchor a tank with.
Originally Posted By J75player:
you anchor it , then you dont have to worry about it floating out
Originally Posted By 44Regular:
A high water table is trouble for a buried tank full of air. It's trouble for a concrete vault if there isn't enough mass or enough pumping.
A high water table is trouble for a buried tank full of air. It's trouble for a concrete vault if there isn't enough mass or enough pumping.
you anchor it , then you dont have to worry about it floating out
The point I was trying to make is that a tank is not going to work without a lot of concrete holding it down, so you might as well just go with concrete. Unless you know of some other material to anchor a tank with.
no your right, you anchor it with concrete. but unlike building a concrete shelter, the steel tank wont leak.
you can keep a concrete shelter dry, but it generaly takes alot of work and some luck with a high water table.
plus, pouring some concrete anchors is alot easier then pouring floor/walls/roof of a shelter.
Any idea how much concrete it would take to effectively anchor a lil 3000 gallon tank? And how much the cost would be??
Why not just pour a nice reinforced concrete shelter and make sure you have a good drain down-slope???
The solution to this shelter problem isn't complicated.
4/21/2012 3:03:01 PM
Originally Posted By EXPY37:
Any idea how much concrete it would take to effectively anchor a lil 3000 gallon tank? And how much the cost would be??
Why not just pour a nice reinforced concrete shelter and make sure you have a good drain down-slope???
The solution to this shelter problem isn't complicated.
Originally Posted By J75player:
no your right, you anchor it with concrete. but unlike building a concrete shelter, the steel tank wont leak.
you can keep a concrete shelter dry, but it generaly takes alot of work and some luck with a high water table.
plus, pouring some concrete anchors is alot easier then pouring floor/walls/roof of a shelter.
Originally Posted By 44Regular:
The point I was trying to make is that a tank is not going to work without a lot of concrete holding it down, so you might as well just go with concrete. Unless you know of some other material to anchor a tank with.
Originally Posted By J75player:
you anchor it , then you dont have to worry about it floating out
Originally Posted By 44Regular:
A high water table is trouble for a buried tank full of air. It's trouble for a concrete vault if there isn't enough mass or enough pumping.
A high water table is trouble for a buried tank full of air. It's trouble for a concrete vault if there isn't enough mass or enough pumping.
you anchor it , then you dont have to worry about it floating out
The point I was trying to make is that a tank is not going to work without a lot of concrete holding it down, so you might as well just go with concrete. Unless you know of some other material to anchor a tank with.
no your right, you anchor it with concrete. but unlike building a concrete shelter, the steel tank wont leak.
you can keep a concrete shelter dry, but it generaly takes alot of work and some luck with a high water table.
plus, pouring some concrete anchors is alot easier then pouring floor/walls/roof of a shelter.
Any idea how much concrete it would take to effectively anchor a lil 3000 gallon tank? And how much the cost would be??
Why not just pour a nice reinforced concrete shelter and make sure you have a good drain down-slope???
The solution to this shelter problem isn't complicated.
I dont think you understand what "high water table" means
4/21/2012 5:39:56 PM
Originally Posted By J75player:
I dont think you understand what "high water table" means
Originally Posted By EXPY37:
Any idea how much concrete it would take to effectively anchor a lil 3000 gallon tank? And how much the cost would be??
Why not just pour a nice reinforced concrete shelter and make sure you have a good drain down-slope???
The solution to this shelter problem isn't complicated.
Originally Posted By J75player:
no your right, you anchor it with concrete. but unlike building a concrete shelter, the steel tank wont leak.
you can keep a concrete shelter dry, but it generaly takes alot of work and some luck with a high water table.
plus, pouring some concrete anchors is alot easier then pouring floor/walls/roof of a shelter.
Originally Posted By 44Regular:
The point I was trying to make is that a tank is not going to work without a lot of concrete holding it down, so you might as well just go with concrete. Unless you know of some other material to anchor a tank with.
Originally Posted By J75player:
you anchor it , then you dont have to worry about it floating out
Originally Posted By 44Regular:
A high water table is trouble for a buried tank full of air. It's trouble for a concrete vault if there isn't enough mass or enough pumping.
A high water table is trouble for a buried tank full of air. It's trouble for a concrete vault if there isn't enough mass or enough pumping.
you anchor it , then you dont have to worry about it floating out
The point I was trying to make is that a tank is not going to work without a lot of concrete holding it down, so you might as well just go with concrete. Unless you know of some other material to anchor a tank with.
no your right, you anchor it with concrete. but unlike building a concrete shelter, the steel tank wont leak.
you can keep a concrete shelter dry, but it generaly takes alot of work and some luck with a high water table.
plus, pouring some concrete anchors is alot easier then pouring floor/walls/roof of a shelter.
Any idea how much concrete it would take to effectively anchor a lil 3000 gallon tank? And how much the cost would be??
Why not just pour a nice reinforced concrete shelter and make sure you have a good drain down-slope???
The solution to this shelter problem isn't complicated.
I dont think you understand what "high water table" means
OP said he was pouring a concrete slab over the top, so does any of this matter? I imagine the slab would pretty much stop the tank from rising. More like a ballast and less like an anchor.
I have no idea though, its a genuine question.
4/21/2012 5:44:56 PM
Originally Posted By sarge38624:
I will be pouring a 12'x24' concrete slab behind my house where I currently have a very low wooden deck. I am considering installing a 8'x8'x8' in ground metal shelter directly under the slab. I have a friend who is a welder, and he has offered to weld everything for me, but I have a few concerns. The sheet steel I have found is sold in 4'x8' sections. I am considering using 1/8" steel for the walls and floor, and 1/4" steel for the roof and door. In theory, I can piece the 4'x8' sections of steel together to make a perfect cube, but I am pretty certain that won't work without quite a bit of bracing. Do you guys have any ideas, links, or experience regarding what I am considering doing?? I AM NOT going to build this thing and put my family in it unless I know for sure that it is safe. I plan to paint the inside and outside of the shelter with something water proof as well. Any insight you guys can give me will be greatly appreciated. Thanks in advance.
I will be pouring a 12'x24' concrete slab behind my house where I currently have a very low wooden deck. I am considering installing a 8'x8'x8' in ground metal shelter directly under the slab. I have a friend who is a welder, and he has offered to weld everything for me, but I have a few concerns. The sheet steel I have found is sold in 4'x8' sections. I am considering using 1/8" steel for the walls and floor, and 1/4" steel for the roof and door. In theory, I can piece the 4'x8' sections of steel together to make a perfect cube, but I am pretty certain that won't work without quite a bit of bracing. Do you guys have any ideas, links, or experience regarding what I am considering doing?? I AM NOT going to build this thing and put my family in it unless I know for sure that it is safe. I plan to paint the inside and outside of the shelter with something water proof as well. Any insight you guys can give me will be greatly appreciated. Thanks in advance.
Your mind will probably change when you see whatever it is coming at you that made you want to build it in the first place.
Anything is better than nothing I would say, as long as it doesn't move you backwards.
4/21/2012 10:30:57 PM
Originally Posted By J75player:
I dont think you understand what "high water table" means
Originally Posted By EXPY37:
Any idea how much concrete it would take to effectively anchor a lil 3000 gallon tank? And how much the cost would be??
Why not just pour a nice reinforced concrete shelter and make sure you have a good drain down-slope???
The solution to this shelter problem isn't complicated.
Originally Posted By J75player:
no your right, you anchor it with concrete. but unlike building a concrete shelter, the steel tank wont leak.
you can keep a concrete shelter dry, but it generaly takes alot of work and some luck with a high water table.
plus, pouring some concrete anchors is alot easier then pouring floor/walls/roof of a shelter.
Originally Posted By 44Regular:
The point I was trying to make is that a tank is not going to work without a lot of concrete holding it down, so you might as well just go with concrete. Unless you know of some other material to anchor a tank with.
Originally Posted By J75player:
you anchor it , then you dont have to worry about it floating out
Originally Posted By 44Regular:
A high water table is trouble for a buried tank full of air. It's trouble for a concrete vault if there isn't enough mass or enough pumping.
A high water table is trouble for a buried tank full of air. It's trouble for a concrete vault if there isn't enough mass or enough pumping.
you anchor it , then you dont have to worry about it floating out
The point I was trying to make is that a tank is not going to work without a lot of concrete holding it down, so you might as well just go with concrete. Unless you know of some other material to anchor a tank with.
no your right, you anchor it with concrete. but unlike building a concrete shelter, the steel tank wont leak.
you can keep a concrete shelter dry, but it generaly takes alot of work and some luck with a high water table.
plus, pouring some concrete anchors is alot easier then pouring floor/walls/roof of a shelter.
Any idea how much concrete it would take to effectively anchor a lil 3000 gallon tank? And how much the cost would be??
Why not just pour a nice reinforced concrete shelter and make sure you have a good drain down-slope???
The solution to this shelter problem isn't complicated.
I dont think you understand what "high water table" means
The 'container' can be 'floated' in different ways.
Fer instance...
A leak around the 'container'/shelter that let's surface and ground water find its way to and surround the buried shelter during heaving rains, etc, and compounded by saturated soil, can float the shelter irrespective of the 'water table'.
Check my math...
An 8 x 8 x 8 x 8 foot shelter displaces about 16 tons of water.
The weight of a 12 x 24 x 4" slab is about 7 tons.
If the shelter's hole fills up with water, even though the tank is surrounded with wet soil, it's possible for the shelter to begin to float.
The best solution is a redundant drainage system -or a far less desirable one are redundant 'sump pumps' of one sort or another.
The concrete cover over the shelter would likely serve to redirect water away from the disturbed soil if planned carefully.
In any case it's something to consider when making the investment.
4/22/2012 9:40:37 AM
I do poured concrete for a living, so this problem looks like a nail. YMMV
Depending on soil type and water table (i.e. Sand or dirt and on top of a hill or water table 9 feet or deeper) this is what I'd recommend.
The concrete underneath the walls will be poured first, then the walls. The floor will be poured next, at which point you can backfill. Then the roof/floor can be formed up and poured. If you have any questions, feel free to ask. That's a 2 minute drawing
Depending on soil type and water table (i.e. Sand or dirt and on top of a hill or water table 9 feet or deeper) this is what I'd recommend.
The concrete underneath the walls will be poured first, then the walls. The floor will be poured next, at which point you can backfill. Then the roof/floor can be formed up and poured. If you have any questions, feel free to ask. That's a 2 minute drawing
4/22/2012 1:50:43 PM
Exactly, altho you could pour the floor and footing monolithically and save a pour.
Where the walls sit on the slab, I'd suggest a bentonite cord, or equiv.
Also, to help keep water that will tend to flow slowly down the side walls sometimes, adding a detail to the footing that slopes the flat footing overhang away from the edge where the wall sits I've found would be useful to help keep water from creeping under the separately poured walls.
Then, a nice piece of roofing membrane fit over the roof would be helpful to reduce leakage from inevitable cracks.
Perimeter drainage under the slab and around it to some point downslope even if the run is some distance is worth its weight in gold.
[I've posted these details many times here]
Water is going to be the issue in a lot of places and there are some more things to do if folks get serious abt building one of these.
Iwouldn'tknow, your detail does take care of water creep under the walls. That the monolith pour wouldn't do as well. It could well be worth the extra pour, come to think abt it.
Where the walls sit on the slab, I'd suggest a bentonite cord, or equiv.
Also, to help keep water that will tend to flow slowly down the side walls sometimes, adding a detail to the footing that slopes the flat footing overhang away from the edge where the wall sits I've found would be useful to help keep water from creeping under the separately poured walls.
Then, a nice piece of roofing membrane fit over the roof would be helpful to reduce leakage from inevitable cracks.
Perimeter drainage under the slab and around it to some point downslope even if the run is some distance is worth its weight in gold.
[I've posted these details many times here]
Water is going to be the issue in a lot of places and there are some more things to do if folks get serious abt building one of these.
Iwouldn'tknow, your detail does take care of water creep under the walls. That the monolith pour wouldn't do as well. It could well be worth the extra pour, come to think abt it.
