Hello all,
A long time customer aproached me this weekend, ya’know I got this idea and I know how you like different projects. Deep breath this fella is a lil eccentric (I hear it takes one to know one). He wants to build a hidden room under a porch and then attach it to a tunnel about 150′ away outta sight. So I’m kicking a few thoughts around, not really a tunnel approach in the sense it will be trenched and backfilled.
1, precast units
2, superior walls with decking and concrete
3, large culvert pipe with concrete for a level floor
thoughts?
thanks
Dan
Replies
Whatever it is it's got to be foil-lined. ;)
One option is to build a sidewalk and put the "tunnel" under that. Helps to hide the excavation and lets you put the top at the surface, reducing excavation depth. But I don't know what you'd use to construct it.
Conventional approach would be to do the whole rebar/pumped concrete thing with floor and walls, and then maybe precast top. But you could maybe use some sort of retaining wall block for the walls, with dirt floor, and precast slabs on top.
Probably all sorts of nasty code issues.
happy?
Re: ..."build a sidewalk and put the "tunnel" under that"I have, on various municipal and industrial sites, seen service or utility tunnels constructed in the form of a reinforced concrete trough wide enough for all the planned plumbing, steam lines, conduits, etcetera and room for a walkway. The floor is usually sloped to one side and on to one or more sumps. Over this is a series of concrete sections that overhangs the sides of the tunnel walls and have some sort of provision for lifting. Some of these installations were designed to be covered with soil. Others arranged as walkways or road for vehicles. The advantage of this is that if repairs or upgrades become necessary it is simple enough to scrape the grass off, screw in lifting eyes and lift the concrete sections off with a crane. It makes the process a lot easier in that you can use longer sections of pipe or conduit without having to thread them down a manhole.Also if you were going to go with a culvert type arrangement with a rounded floor I would resist the urge to pour concrete to provide a flat surface. IMO it would be far better to provide a removable flooring that would provide a space underneath. Wood duck boards or concrete sections might be an option. The idea being that few things underground, outside a desert, stay absolutely dry. A floor incorporating a hollow section that allows water to flow toward a sump while keeping the feet above the flow. I would keep the flooring removable so facilitate cleaning or removal of stoppages. Lighter coverings being easier to shift by hand but possibly less stable.There are concrete or metal culvert sections commercially available. The ovoid concrete sections of something like 8' by 5', if turned on end, seems to be ideal but these sections are not something one would install single handed. Most seem to come in 20' section but even the 10' ones are nothing like light. The 8' would give you 7' of head room even given a 1' for walkway, drainage and, perhaps, some overhead lighting. The 5' width giving you plenty of room for utility lines or storage on one or both sides while maintaining 3' of walkway.Laying such sections is a matter of digging a tench, laying in gravel, setting the culvert sections and dropping in gravel in small lifts. The final step being soil and landscaping.If your preference ids for site built structures you might use tilt-up concrete methods to build walls which would be laid in a trench and tilted into each other to form a 'A' frame. Sections might need to be perhaps 6" thick reinforced with steel. 10' tall and as long as you could handle. These might be set vertically and then gravel dropped between the sections to keep the feet apart. Once a run is laid in and covered with gravel excess gravel is removed from the floor area and concrete could be poured over it to give a solid floor. Of course the 'A' would need to be perhaps 10' on a side to allow some elbow room and a 6' or so floor. The 'A' geometry of such a structure naturally tends to deflect loads away from the structure. Even more than a ovoid geometry. This property being valuable in some situations. Like when they go Waco and bring in the tanks. Better you should be mobile.
I have had the same idea too, but as a hurricane shelter
Precast concrete culvert would work, and if he keeps a few mechanic's creepers in the room (depending on how many people need to escape), he can just use his feet to power himself out instead of crawling on his hands and knees. Until last week, I worked for an A/V contractor and was surprised by the number of homes with safe rooms. OTOH, these were very large homes and I doubt that there were mortgages involved, so they could definitely be targeted.
"I cut this piece four times and it's still too short."
I can't imagine having enough time once the assault is sprung to make it to the tunnel. They don't call ahead. I'd push hime towards preventing, and then reppeling an attack instead of running from it. I can't imagine that an escape would work.
Of course that's not what he wants to pay to hear.
http://bootliquor.com/
After reading all the thoughts...yes this seems like a lil strange thing to want. This fella is sorta the mad scientist complete with lab. I think the home invasion idea is to make it a lil more palatable to the missus. I'm anxious to here from a past costumer that does precast work as it seems thats where most of your posts lead. I still wanna get some prices on large culverts as well out of curiosity.
Thanks again
Dan
Coolest: the pre-cast concrete sections with enough height to stand.Cheapest: corrugated metal culvert. 24" or bigger. The bigger the better, but more $$ because of the larger diameter and thicker wall.Transit (if not standing height): mechanics creepers/skate boards as mentioned. Or, better yet, a rail system. Cheapest would be two runs of 2" flush-threaded PVC pipe (call a drilling company)18 or 24" apart. Or make your own internal couplings. Then adapt something like the rollers on a boat trailer to run on the pipe and keep one or two such trolleys at each end.Having had some moderate experience at this (caver, civil engineer, attended culvert parties at UC Berkeley, examined heat- and cold-trapping caves and mine adits) I have a few more thoughts:A low spot will trap cold if you allow (don't almost completely prevent) air movement in the winter. In the summer, cold air will stagnate low. In the winter a convective current will establish and cool of the culvert and surrounding ground. In snow country and deeper than about 5 to 8 feet and you will freeze enough soil moisture to maintain 32F through the summer.Lighting: When caving I have three sources of light. Obviously strap a flashlight to the each of the trolleys. And keep headlamps on a hook at each end. But do you also want a lighting system? Some of the "light ropes" might do nicely. Might be cheaper to install with strong magnets (for seel culvert) than to drill and bolt it.Waterproofing the joints is going to be tricky. Pre-cast can be had with gaskets. Slamming them together takes some force. Doing it without bunging up the gasket takes some skill. For metal culvert, maybe wrap in 20-mill poly, seal with tape, secure with the bolt-together couplings and/or pour with concrete around each joint. One every 40(?) feet.Easy transit with a trolley suggest a level grade and periodic sumps. Ease of water handling would be to pitch the whole thing and have one sump at the bottom end.David Thomas Overlooking Cook Inlet in Kenai, Alaska
I work in tunnels in bank drive ups occasionaly. Consider some sort of sump pump. And a light system. Another thing to be aware of is the presence of dangerous gases. You'd be hard pressed to find a utility worker in this country that will go in one without a gas sniffer and a proper resperator. You might not notice anything at first but if you are down there for a prolonged period of time, it can effect you in a big way. Think mold. It aint good to inhale that. So then I guess you have the burden of ventilation.
There's a lot of stupid things to consider if your going to do it properly.
http://bootliquor.com/
"but as a hurricane shelter"Doesn't a hurricant dump a lot of rain? Not sure if I'd want to be in a culvert tunnel waiting it out. ;o)
I always said that if I ever build my own house, i'd put a tunnel from the house to the garage/shop. Never really considered how i'd do it though. Maybe preformed walls. I like the side walk on top. Good idea.
I have no idea what the cost would be, but I imagine the culvert pipe approach would be feasible - I have thought this through before...I have heard that some college campuses in cold climates have extensive tunnels, and I think it is Monticello that has tunnels from the garages (below the main lawn) to the house.
8' plastic pipe, form a sidewalk down the middle, drains at the side to a sump...
I wanted a tunnel between our house and (eventual) pool house, but my wife thinks tunnels are creepy.
I lived most of my life in a midwestern university town. The campus is absolutely criss-crossed with miles of tunnels these tunnels have all of the heat pipes, phone, gas, and electrical lines for all of the university buildings running through them. and they consequently link up all of the buildings together. When I was a teenager it was great adventure to go skulking about down there, exploring. there are even a couple that run beneath the large river which runs through the middle of town. For a long time there was a pretty large community of bums (you can be P.C. and call them homeless people if you wish.) living down there. not unlike that T.V. series "beauty and the beast" from the '80s. They weren't the friendliest people to run into while you were down there.
Anyhoo, back to the actual point of this post.
I too have always thought it would be cool to have an escape tunnel leading away from the house. And my own private "bat-cave". My idea was that it would be easiest to just do it like a normal basement. Good gravel base, for drainage, followed by a concrete floor, followed by poured walls, followed by a concrete cap. with a waterproof membrane atop that and then a couple of feet of dirt, sod etc. and there ya have it! I doubt that I could ever get this idea past the wife though, so I've never even tried." If I were a carpenter"
That sounds fun - sneaking around - kinda like the "elevator surfing" we did in college. But not at all what I pictured for tunnels.
I had the idea that at some Chicago universities you never had to go outside in the winter - you could go to the dining hall, class, wherever, underground.
I agree on tunnel size - if you're gonna have tunnels - make them walkable (and with shelves for storing ammo, Y2K food and Star Trek memorabilia:-)
Treat every person you meet like you will know them the rest of your life - you just might!
" Star Trek memorabilia"
I hope you're not including stuff from the last one with Scott Bakula. Or, for that matter, Voyager.
Shep - I thought I might ruffle a few feathers - most of the stranger folks I've known were Trekkies - not that there's anything wrong with that.
Treat every person you meet like you will know them the rest of your life - you just might!
didn't ruffle my feathers- I'm a huge sci fi fan,
even bad sci fi
I just thought they could have done a lot better with Enterprise
most of the stranger folks I've known were Trekkies
LoL! That's because the True Fans are "trekkers" not "trekies" <G>Occupational hazard of my occupation not being around (sorry Bubba)
never spend more than you can afford to loose.
Hey! Enterprise is way better than V'ger (ST's "Gilligan's Island," we can't get home, we can't home--but we can get the Federation in a couple of interstellar wars and find a Borg with inverse multiple personality disorder . . . )Occupational hazard of my occupation not being around (sorry Bubba)
but you've got to admit that Borg looked pretty good in that jumpsuit
Borg looked pretty good in that jumpsuit
never much of a shortage of well-filled lycra or similar fabric on any of the ST franchises <G> . . . Occupational hazard of my occupation not being around (sorry Bubba)
I went to school at the University of Minnesota, and there are tons of tunnels there. They even have some buildings entirely underground; the bookstore is underground, and the the civil engineering building is way down there - it's 110 feet below grade. It even has a light shaft with mirrors in it, so you can look out a 'window' and see people walking around up on the surface. You can't get everywhere underground, but quite a few buildings are connected.
I grew up just outside of Rochester, and the medical complex there is interconnected with tunnels as well. You can pretty much get anywhere without having to go outside, which is convenient for patients. There are stores, places to eat, pharmacies, etc. down there.
yea, the UMN is a massive maze of tunnels. I work in St. Paul in the capital complex, also entirely connected via pedestrian tunnels. I assume (as mentioned) that there are actual tunnel products out there for just this thing.
Universitie Laval (sp?) in Quebec is similarly interconnected underground, as I understand it.Mayo Rochester used to be almost 100% underground, but then they got on a skyway kick, and now you gotta use skyways for a few of the hops.
If ignorance is bliss why aren't more people
happy?
I'm voting for the precast culvert, maybe 5' dia. Whatever you do it will probably want to fill up with water, so provide a sump.
Thanks for all the replies.
I'd thought about the walkway on top, but coolness playes a huge factor in this job and hey we all need a lil coolness, he wants it to exit in a pasture like way hidden.
One of the parameters is that its a storm shelter.
No hvac as of yet but passive airflow is a must to prevent mildew.
In leiu of creepers how about skateboards? Here in western pa about 15 yrs ago they put a 24" gas line under the little creeks and stuff I thought it would be a great cheap rush to go under the creek on a skateboard before they welded it all together hehe.
Im calling the inspector tommorrow before I get to much time invested.
thanks for al the thoughts,
Dan
If nothing else, it would be a neat way to run utilities to an outbuilding....
-- J.S.
about a tunnel like on "Get Smart" with all the sliding doors.2+3=7
ok....he wants hidden doors too...LOL
the coolness factor
Dan
*edit* I did suggest a elevator and missle silo style doors...he thought that was a bit much
Edited 11/21/2005 8:34 pm ET by DBlacky
I would vote for the Concrete culvert w/seals cast in the ends, 7-8 ft dia so that you can put a flat walkway in it.
He wants this as a hidden enterance so you can't talk to the inspector . This has to be done on the sly.
Is the guy a shooter? With a little ventilation it could be a great all season shooting range!
You sure this guy doesn't have any relatives/buddies in Afghanistan...? <:o)>
If you're satisfied he's legit and just a bit balmy, and that building this won't get you six feet of free real-estate or a permanent 'office' in your own excavation (forgive me; I read too much E.A. Poe as a kid...), I'd think pre-cast culvert would be the KISS solution. Check with a contractor who does work for the local utility company installing underground power feeders. He would have the most appropriate info for doing this kind of stuff in your area.
In western PA, you have to think of mine subsidence issues, too, not a small consideration for any kind of dig you want to remain relatively dry and 'habitable'. Another thought--any mine fires burning out there at the moment?
Dinosaur
Hold your ground!
I see in your eyes the same fear that would take the heart of me....
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
--any mine fires burning out there at the moment?
Always.
We just had a large flare up in a county park, about 3 miles from my house. A beautiful park, with acres of forest, it basically had to be strip mined to get the fire out. Now, there is just a bunch of 1" saplings growing on the hillside. I'll have to get some pictures, it's enough to make me vomit.
Stacy's mom has got it going on.
Edited 11/21/2005 10:05 pm ET by dustinf
Does make ya wonder about the wisdom of building anything that's not eminantly portable in such an area. OTOH, my mother lives south of Pittsburgh in a McMansion....<;o|~>
Dinosaur
Hold your ground!
I see in your eyes the same fear that would take the heart of me....
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
Does make ya wonder about the wisdom of building anything that's not eminantly portable in such an area.
We don't have enough tornadoes for trailers around here.
Stacy's mom has got it going on.
You got it backwards: tornadoes don't attract trailers, trailers attract tornadoes....
Dinosaur
Hold your ground!
I see in your eyes the same fear that would take the heart of me....
A day may come when the courage of men fails,when we forsake our friends and break all bonds of fellowship...
But it is not this day.
I think many precast culvert companies also build precast pedestrian tunnels. They're sort of egg-shaped, with a flat bottom, and are tall enough so you can walk upright through them. If the guy wants a tunnel, he may as well have a comfortable one.
i've got one of those out of my basement.. put it under the garage.. and across the driveway... to a chamber with a concrete cap.... i could hide the exit if i wanted to ..
it was originally built as an "earth-tube" for future fresh air inlet.. but i never hooked it up to a blower system
i used 30" aluminum culvert pipe.. i bought the 10' cut-offs from the highway department
all-in-all it covers about 60' underground with one bend..
me and all of my nephews have crawled thru it... but no one in about the last 15 years....
one of these days i'll take the inside cover off and show my grandson.. maybe we'll crawl thru it ... kind of like Alice-in-Wonderland...
for crawling.. you don't need a floor.... if you wanted to do it up like " The Great Escape".. you could pour a floor and put some mechanics creepers in it for pushing yourself along on your back
I've always been totally fascinated by the idea of underground tunnels.
Towards the end of the Viet Nam war it was revealed that that some of the major cities were criss-crossed underneath by literally hundreds and hundreds of miles of intersecting tunnels. They had Hospitals, nurseries, food storage rooms .. the works.
On an only slightly unrelated note my other interest has been a safe room -- maybe a bathroom since it has running water AND any 'home-invaders' wouldn't deny you use of it -- I've always thought .. with bulletproof walls. A year or two ago I tried researching materials for bulletproofing ... some 4X8 ft. sheets cost around a thousand bucks a piece! I always thought there must be a 'poor mans way' of doing it .. but haven't found anything about it yet.
They say that the Medellin Cartel in Columbia always hired people to install long tunnels leading away from the house from the lowest level under new properties that they built. Word is that whomever saw the plans or worked on it in any way was killed before they left the property after completion. (Discovery Channel)
Terry
Dan,
Is the homeowner, uh, "connected". I live in the Chicago suburbs and there are a lot of old farmhouses on outskirts of the suburbs that were used by Capone and his gang as safehouses.
We does this guy need a tunnel? Just curious.
I have to say when I first read the title, I immediately got this vision of a horde of vikings or pirates, digging their way into someone's basement from next door...
A soldier will fight long and hard for a bit of coloured ribbon. - Napoleon Boneparte
Anybody here see Silence of the Lambs?
Would you want to be part of what it COULD be for?
FBI might...
1. How about a giant pneumatic tube, like the ones at the drive in bank? It could slope up at daylight so the guy could launch himself back into outer space.
2. A giant potato gun would accomplish the same thing. The whole point is a quick getaway.
"How about a giant pneumatic tube, like the ones at the drive in bank? It could slope up at daylight so the guy could launch himself back into outer space"Or he could lure the bad guys into it and shoot them out instead. Aim it towards the nearest police station, they're all nice and bundled up, ready to go to jail. Like an old rerun of a Batman episode.
There is a concrete tile place on the NE side of town. I've noticed some pretty big sections of square, concrete, interlocking tiles (like big, sqaure, concrete drainage tiles). You'd need a big-#### crane, but in theory, you could just excavate, crane the tiles in, waterproof, and pile the dirt back in.
As several people have mentioned, waterproofing/barrier is a serious issue if he doesn't want mold, radon, etc, etc, seeping into the passageway. Also, if he doesn't bury it deep enough, it might still be visible from the top.. in winter you might end up with the snow melting differently on that strip. In dry summers, that might be the first place the grass dies. (but these could be dealt with by putting a bit more dirt overtop)
jt8
"Politics is supposed to be the second oldest profession. I have come to realize that it bears a very close resemblance to the first."
-- Ronald Reagan
Edited 11/22/2005 10:07 am by JohnT8
Osama? Abu Musab? Dick Cheney?
Brings to mind this story from Syracuse. Who else knows about your client's planned "hidden room"?
http://www.usatoday.com/news/nation/2003-04-21-dungeon-details_x.htm
Surprised no one else mentioned it but in Robert Heinlein's "Friday" one of the characters is an architect who specializes in home security (in a nasty future history) and there are some details of her own escape tunnel. How to hide the controls from unfriendlies (in the glare of the lighting), the in-house entrance (which is through a sump under the bench of the whirlpool) and the body disposal technique (acid).
Good book, BTW. Read that years ago.For me it comes down to how to prevent others from figuring out what you did before they make their assault. Saddam Hussein found that out the hard way during the first Gulf War, when the Americans got the skinny from the Swedes as to which vent shafts to target with their laser-guided bombs. Then there is the matter of being able to trust the folk who build the stuff not to blab about it to their friends. This is one area where subterranean DIY work without disturbing the ground above may make a lot of sense...Lastly, there is the crucial issue of detection, i.e. to have enough warning when someone is trying to creep up on you for you to make the necessary escape. In most building environments, one doesn't have the necessary perimeter and/or active defenses to cover all the approaches in a systematic manner.It's probably cheaper to have few enemies than to have to prepare for some truly ticked off people.
Re: "Then there is the matter of being able to trust the folk who build the stuff not to blab about it to their friends."Humans are so very poor at maintaining and protecting secrets. Legend has it that the Ghengis Khan was buries with a huge stockpile of treasure. Story goes something like this:An army of laborers and engineers protected and contained by a small army of warriors were sworn to secrecy. They marched into the wilderness and spent months on the burial site. When done they have a huge feast and celebration followed by the army killing the laborers. The engineers and army, having done their duty, start to march back. Half way back they are met by another small army. Which kills them to the man.This second army upon returning to the city are wiped out to the man. None left to give away the secret. Little chance the secret is transferred from one group to the next.If you want to keep a secret you have to limit the number of people who know. Old saying is that if you want three men to keep a secret you kill two.It is hard to do any major undertaking without causing ripples. One of the main tools the UN inspectors in Iraq used to find potential nuclear laboratories and prove there was no program was simply to follow and monitor power lines. A program uses a lot of power. And if it is not conducted to the site it has to be generated at the site. Which uses fuel and generates heat. Neither are easy to hide long term.A number of marijuana growers are caught every year because power companies monitor power use. A sudden but consistent uptick can mean a faulted power line or meter. I have heard some building inspectors maintain contacts with concrete suppliers and watch delivery trucks, concrete and lumber, to give them clues where unpermited construction is going on.Also any underground excavations face the same problems shown in 'The Great Escape'. Where to put the spoils. Doesn't take many cubic yards of dirt to make a pretty impressive pile. A pile that can catch the eye of appraisers or silt up a stream and attract the attention of the environmental authorities. Even the movement of construction vehicles muddying the roads is a clue.Not to say it can't be done. Hasn't or isn't being done. But there area lot of aspects to consider. Inputs to obscure. Outputs to conceal.
I have heard some building inspectors maintain contacts with concrete suppliers and watch delivery trucks, concrete and lumber, to give them clues where unpermited construction is going on.this is true in my hood. the permit dffice is across the street from the concrete plant.2+3=7
What??? You mean this isn't a thread about subterranean termites?
Go with #3.
First off, you can sub it as a straight forward drain pipe and have it sealed & waterproofed properly. Sub goes "wha'for?" tell him HO wants to do some future rainwater storage or the like. Sub meets the HO, and will come a way with the same "excentric" label you did.
Also, you can get stock box-shaped manhole accesses to fit the culvert, too.
Lastly, rather than pour a concrete floor, I'd use duckboards, They're much easier to fit, and they give you a "bilge" space for any moisture condensing on the inside of the cuvlert. A mechanic's "creeper" means not needing quite so big a bit of culvert diameter, too.