Building down under ground level

The problem with sub-surface structures is water. Rain coming in, stopping it, getting rid of it, etc. The building needs proper design. Many years ago leaking hydrochloric acid tank was turned into a boat by the inadvertent effect of using too much water from the works fire engine so as to cause the tank to float away from its moorings. Many do not stop to consider the uplift available by a subsurface structure placed within a piece of ground where the water table is high; an empty septic tank is an example.

Designing the building, and the liability for incorrect design, is a task ideally entrusted to a specialised building design technician or architect, and periodic inspection as part of the construction procedure by the relevant local authority. Then, when something goes wrong with an item representing a considerable investment, one has redress.

If you really, really want to do this, I advise you to talk to an architect. He can give you more options to get what you want to achieve.

One problem (other than the water thing) is that sound carries through solids much better than through air. You may have to isolate your equipment from the floor via rubber feet or something similar. Then your walls, ceilings and doors will have to have an sound absorbent layer. An alternative would be to have double walls. How much sound proofing you need will depend on how noisy you are.

Above ground would still need the same treatment but avoids the complications of burying the building. This way, you won't need a hoist to bring large objects in or out. You can soundproof the door by hanging a heavy curtain over it.

Security? Just have the door! No windows!

How you gonna breath? Your ventilation system will have to be soundproofed also (true for above ground or underground). You could buy an oxygen tank and crack it open but that would be expensive (and dangerous too, by the way).

Aw heck! Just build your shop in an industrial area!

I think I am going to abandon this idea of building under ground.... Rather spend my money on more soundproofing... Thanks guys for the advice. Maybe one day if I buy property with a steep slope, then it will make sence to go into the ground. I also thought of going to an Industrial area, but then I will have to buy another property or rent from someone. At the moment I have this huge space (about 200m2) and it is where I live...

Ok lets be logical the cost of going under ground is 2 to 3 times the cost of building above ground. So if you don't have to leave well alone. But that said the following may well help. Dig out a hole 1 1/2 times the volume required this is to let you have enough room to work and install the required thickness of walls and floor. You need to build a room in a room in effect. The outer wall being the secret to keeping dry. A concrete wall is cast to begin with this has to be thick enough to resist and pressure from soil and water. next a water proof plastic membrane then the insulation and finally your inner wall. Roughly 3 feet in total. When all is in place and the mortar has gone off you can back fill the outer wall. The floor should be a concretye raft with a suspended wooden inner floor the conrete is laid first and then a membrane added with a second screed foor to level it. The wooden joists should by laid onto isolting pads so as to prevent down ward noise problems (low frequency is the main problem) Rumble goes for miles. The getting in and out is solved by a hydrolic lift. (you need a second pit for the piston unit pump etc.) The lower wall section needs to be sized to carry the loading of the upper structures weight keep thios on a strict diet. Next you need to know how to isolate the noise from the verticle path this can be done by a suspended flooring and general good building practice, add sound absorbing materials like chopped glass fiber insulation under the upper foor layer. I have to go now but will be available later if you have any questions.

Cast in place reinforced concrete is best. If using cinder block,2 coats of 50/50 portland cement and sand, 24 hours apart, and wet cured is an effective water barrier.You need to install a french drain, which is a trench around the perimeter,below floor level, with gravel under and over a perforated drain pipe, leading to a sump with a float switch.Poured concrete floor should have plastic under it to help prevent moisture.Spiral stairs take up the least space, but difficult to move large objects up and down.May need a trap-door for large items.

If you pour concrete walls, have the builder "Key" the walls to the floor by creating a modified rabbit joint in the floor when it is poured at the points where the walls will join the floor.Also lock rebar from floor into walls for strength. There will be a lot of pressure from soil on the walls.

Local codes will dictate materials and methods, so check with your local inspector for tips and advice.

What im doing is earth berm house, best of both worlds sorta, I am planning on using ACC block, With earth bearm you contain noise or keep noise out, why dig a hole??

craig

This sounds like a basement buried deep enough to cover any possible windows. Outside entrances to basements are not at all uncommon (I have seen them advertised in Popular Science and Popular Mechanics, generally towards the back of the magazine) and you will want a set of stairs to the main living quarters. Any reputable contractor should be able to help you with this. Depending on how high you want your basement cieling to be there may be plumbing considerations if the floor will be lower than the sewer connection.

The contractor will know about water proofing and insulating as well as weeping tile/drainage systems that installed around the outside base of the basement. Basements are generally coated with some form of tar or asphalt to prevent seepage through the actual concrete. The insulation and vapour barriers are standard parts of a well designed basement. There may also be local building codes that govern this.

Check the codes, find a good contractor, perhaps check with someone who specializes in basement construction, and have fun in your private world.

You've already decided not to do this but if it comes up again I would first check it out with the local building codes. I have no idea of your local situation. But where I live, the codes spell out the minimums that are required and those that must be adhered to. For example, anything described as below grade living space or work space must have it's own egress to the outside by specific dimensions. Sometimes they actually prevent you from doing a better job because trying to get a variance is a lifetime project in itself.

The homes in my area all have full basements and we live near large lakes so the water table is high. The people that wrote about the problems keeping it dry, and the force caused by flotation, aren't kidding.

Noise reduction / containment: the trick is to construct a room within a room, as someone else has already noted. How? Walls are hung with resilient channel, a metal extrusion fastened perpendicular to the vertical studs. You want mass in the walls to absorb sound, so use heavy grade (1/2") gypsum board or better - remember moisture issues underground - use concrete board. CGC in Canada has a variety of building guides that cover the use of resilient channel (see http://www.cgcinc.com/handbookAssets/PDFs/e/Handbook_12574_CP_C10.pdf & http://dsp-psd.pwgsc.gc.ca/Collection/NH18-22-90-246E.pdf at CMHC for design guidelines; the Wall & Ceiling Industry Assoc at http://www.awci.org/buyersguide/index.pl?division=9&detail=09210.6 in N America for materials supply, but you're on your own overseas - thank G-d for google. The resilient channel is light - if you have to import shipping costs shouldn't be prohibitive; it isn't the kind of thing you'd find in some countries yet). CGC is a big fan of gypsum, but the stuff is a sponge for water, and below grade moisture is major: go fibreglass-wrapped cement board.

Behind the wallboard insulate with Thermafibre sound attenuation blankets - denser than standard fibreglass bats. Roxul works well too & is denser, doesn't harbour insects or vermin, doesn't irritate skin & no dust risk (a kind of fibre made from blast furnace slag, looks like dense fibreglass). Don't screw it up by fastening the wall to the floor in any way: the wall hangs with a slight gap between it & the floor, which you can cover with moldings fastened to the wall. And the floor? mount the wooden sub-floor on rubber pads or, if you're expecting strong vibration, isolating springs set on rubber pads. Ceiling can connect to walls, but it gets hung with resilient channel too, and best if not actually connected to the walls - everything vibrates separately, so the enclosure doesn't act as a sound chamber. Remember to allow for vibration isolation in making any connections through ceiling/walls for ventilation. Air ducts can carry sound too; baffles help reduce sound conduction but greatly reduce airflow which must be allowed for in heating/airflow design.

Moisture: your biggest enemy in underground construction. As noted by others, water vapour pressure can exert tremendous force & literally lift the building if there aren't allowances made (of course, dependent on presence of water or moisture - have a site eval done by a soils engineer & allow for local climate). You keep water out by draining it away, so ensure there is somewhere for weeping tiles & a drainage system (laid out under the floor) to drain. Building on a hill helps. Install any moisture barriers on the outside of the floor & walls - vapour pressure will defeat anything installed on the interior, and you can't easily make concrete impervious to water vapour, so don't even try (vapour pressure will crack the floor if it can't escape around the outside of the structure). Inside the key to keeping things dry lies in ventilation: you have to allow ventilation space under the subfloor and ensure air flow across it, if necessary with active pressure (ducting and fans), though for most houses floor vents around the room perimeter will suffice. If the area has high radon levels in the soil (some places do - see the soils engineer) then ventilation around the outside of the structure and/or especially under the floor is critical: you intend to spend considerable time below grade, concrete is porous to radon but plastic vapour barrier isn't, and a well-insulated structure with limited fresh airflow can accumulate enough radon to increase your long-term risk of cancer significantly.

Back to sound attenuation: your biggest problem is with low frequency noise; we've attenuated higher-frequency sound with interior surface coverings, the separately-hung walls & sound absorbing bats behind it. You can float a house floor on wood 2 x 4s and allow sufficient room for airflow & venting, but while you risk making the subfloor airspace a drum you can't easily add sound attenuation insulation: you need the airflow, rodents/insects will love the insulation for nests if they ever get in, and you don't want to defeat drainage (you will have drains, right?). Mount heavy equipment directly to the concrete floor with its own rubber mounts and build the floating floor around (& just slightly clear of) it. A friend poured the floor of his basement recording studio over a thick layer of high-density styrofoam; hard to tell how much that helped but it may have. Certainly made it warmer.

Light tubes can help reduce lighting costs & improve livability, but allow sound to escape. Fibre-optic light pipes don't, if money's no object.

Don't skimp on ventilation planning: a workshop below grade is a sealed box, and workshops produce dust, fumes & vapours that are irritants at best, toxic at worst. Vibration denotes machinery, so you'll have fine metal dust at very least, if only from electric motor brushes. Long term a health risk. The place will have to be made to stay clean (vacuum extraction around workfaces) and be easily cleanable (whatever builds up, you breathe). And unless you can provide an enormous amount of air movement I think work with finishes, paints or solvents would be out of the question.

Which brings up fire hazard: you want multiple exits, ease of access, and active fire control: you can't just jump out the window. Sprinkler systems make sense & aren't radically expensive when installed in new construction, but if you ever trip them the place better have been made waterproof & very well vented so it dries quickly & thoroughly or you'll never get rid of the mold (another health hazard), and you'd need substantial drainage capacity or sprinklers / firefighting would turn the place into a water tank, creating lots of other problems (water & substantial electrical supply don't mix well). Access for heavy equipment: forget circular stairways or lifts (the first is the antithesis of easy access; the second very expensive). Build a ramp with direct outside access for ease of equipment installation / work removal, and for safety.

Speaking of which, this all assumes what you want to do can pass muster with the local building & fire codes. Aside from being there to protect the neighbours & any subsequent purchaser of your building, the fire code is there to help protect the fire dept. from having to enter a death trap to save your sorry butt in the event that things get hot (happens in workshops, no matter what you expect). If they won't sign off on it, you'd be best to look at an alternative: perhaps a well sound-proofed above-ground workshop. Underground's starting to sound non-trivial, isn't it? Works fine for living quarters, but workshops? Hmm....

Security: World War III protection? We'll all have bigger problems than surviving the first 30 minutes underground. If the neighbourhood is the safety problem, move. Why live and invest heavily anywhere you have to hide in a bunker? Build at ground level, or get out of town, Jack.

oomsarel

All the above comments are good and may or may not be relevant to your project but I will add a comment or two anyway. What I know about sound management and acoustic treatment comes from building radio studios--which don't have necessarily the same criteria as a shop. Here's what I think.

The underground structure is best suited for a hillside property for several reasons. The excavation is simpler, the ground level access is easier, and water management is more straight forward, and it is less expensive. Many people feel that a house is not a home without a basement, which is essentially what you are talking about. Many times people who think they are building a basement actually end up constructing a wading pool. It can be done correctly but it is site specific in its requirements and requires expert design and execution. Soundproofing a basement is not all that difficult. I'll talk about acoustic considerations in paragraph three.

Building above ground with either conventional methods or various alternatives is less expensive and can be made to meet your objectives concerning noise. It cannot be hidden as easily nor will it provide protection from nuclear attack unless you build it as a bomb shelter and just choose to use it as a shop. I decided to respond to your post partly because I am currently planning how to use an old concrete bomb shelter as a recording studio. The studios I have built have always been retrofits of existing structures and have always involved compromises. Starting from scratch is a much better way to go. Now lets talk about the acoustic stuff.

The place to start with sound treatment is to first determine what kind of sound (intensity and frequency primarily) you are going to be dealing with. Understand that you can never make sound energy go completely away. Long after it can't be heard, It will manifest itself as heat at the molecular level for crying out loud. What you have to accomplish is get it below some particular level for the environment it is in. You can get into a lot of acoustical engineering here in terms of decibels of reduction and the logarithmic curve of human hearing, etc., but that's probably overkill for your project. There are only a few things you can do with noise. You can reflect it or you can absorb it. In fairness to Dr. Bose I should note that you can sometimes cancel it with identical sound energy 180 degrees out of phase, and you can sometimes change its frequency with careful physical or electronic manipulation. In your case you need to reflect it (to keep it from getting outside and bothering your neighbors) and absorb it (again, for the same reason). The only other thing you can do is not generate it in the first place.

Start by choosing a method of construction that will reflect sound as opposed to transmitting it (like a big drum head). Standard stick-built construction builds big drum heads, not only in the walls (which usually are only 8' or 10' high and often broken up with doorways and corners, etc.) but even more so in the floors and ceilings. Pay particular attention to floors. Think about an out-of-balance washing machine on a wood floor that is roughly resonant. You don't want that happening. A vibrating machine will telegraph sound for a long ways through a structure. Isolate the machine from the floor that it rests on--or isolate the floor from the rest of the structure--or cause the structure to not be resonant by adding mass perhaps. Adding mass works better at the higher frequencies--say 100 Hz and up. Something as simple as a shipping pallet on a layer of sandbags on a concrete floor is remarkably effective most of the time. Low frequency "thudding" is the most difficult to handle.

If you build a "basement" above ground with one foot thick poured concrete walls, floor, and roof (like my bomb shelter), you will have no sensible sound (at least in the human hearing range) escaping, but it will be bedlam inside with your table saw running. Actually, a poured concrete slab with insulation under the slab on dry gravel for drainage and concrete block walls is a pretty good place to start and it can be aesthetically pleasing from the outside. You will probably want to fir the walls out with insulation and sheet rock for thermal reasons as well as sound control. The ceiling and roof structure is going to behave like timpani so you must absorb the sound energy before it gets out. Actually, directing the sound energy upward and attenuating it to the max works pretty well. Doesn't work too well if you want two stories with living quarters and bedrooms overhead however. There are numerous tricks for walls--like doubled offset studding, double sheet rock, sound absorbent filler, even thin lead sheeting that will reflect and absorb essentially all noise even in stud wall construction. People usually worry too much about the walls and ignore more productive avenues to reduce the sound levels. Ultimately, you go to a floating "room-within-a-room" but that is overkill for your project. You can use the the thin lead sheeting in a ceiling I suppose but you basically just have to use enough sound-absorbent material in the roof and ceiling to get the noise down to an acceptable level.

All this good work is wasted however if you decide you want picture windows and French doors on your shop. No windows at all and double solid-core doors with excellent weather stripping in an ell-shaped entry way is the best way to go. And of course with the room sealed up that way (and it must be sealed--remember how wave energy behaves even through a pinhole) You must have air handling of some sort. Intake and exhaust air need to travel a long ways in a circuitous route at low velocity (read large, high-volume, insulated ducting) through a sound-absorbent system to avoid negating all the other good work you've done.

And finally, it might be simpler and less expensive to run your power tools in the afternoon when people are mowing their lawns and otherwise making noise and save your late nights for handwork like stripping old furniture or designing your next project--almost anything except blacksmith wrought iron work on your anvil with the forge cranked up to red heat.

Jeez--I've written another book. Oh well, its fun.

Lonnie

I've seen a few building programme of this sort on Discovery.

Solid concrete walls with waterproof membrane linked to some form of drain.

Sump internally in case of flooding.

External or internal trapdoor for access.

I have a (woodworking) workshop that I use every day in a resort town. It lives in the garage and the car has been banished to the driveway where it lives under an expensive v good quality custom cover. I have found that noise is not a problem. The only sustained noise is the table saw and band saw and I have learned that in about 20 minutes I can cut enough material to last for 3 to 5 days if I plan it correctly. Thus I do all the noisey work only once a day in the cool of the morning. Everything else like fitting and drilling and sanding and glueing and fastening and painting and drinking coffee and resting and thinking and thinking and goofing off quietly consumes the remainder of the session. I can tell you what the real problem is - heavy copious sawdust, fine cutting related smoke and micron sized wood haze fumes (a fine almost smokey mist sometimes when the cutting is heavy) paint and solvent fumes and also local work generated overheating leading to sweating onto the workpieces and eyeglasses at awkward moments. Thus I have invested in very best quality fume extraction fan systems and high quality 1 micron wood dust recovery systems and dual air conditioners.....You will find that noise isn't the biggest problem by a long shot, unless you can only work to a full tilt boogey boom box background.

Thank-you all. Never thought this thread will go this long... Just shows you that although it is not always such a good idea to build a basement, there is something very authentic about the idea. In my country it is not common to have a basement at all. We don't need heating systems and everything works with electricity. Warm water geisers are up in the roof... I think the main reason for the existance of basements is probably for those reasons. Especially gas heater systems. Hot air rises and where do you put those big furnaces. Now today these devices are smaller, more effiecient and basements you only find in older houses... But I am still dreaming of one!

Go on make the dream happen too many people have spent time and effort in explaining how to for you to let us down you could have a blog an Q & A session for those who like to give forth their brain power, It could even become compulsory for every one to contribute their knowledge.

Get digging Oomsarel we all want to come and vist you to see just how you got on.

might be digging my own grave!!! Wel, I am off on a short holiday down to the coast... Enjoy your week.!

Lucky fellow, the only holiday I get is when I some times get to sleep.

Holiday is a choice. I actually have a lot of work, but I am overworked and not effective in what I am doing. So I just decided to go away to refresh myself. You must try to just go...

Your goals are worth remembering. There are real benefits to being underground--including stable temperatures, negligible costs for heating and cooling, greater security. The other posts have all mentioned problems, but in my experience, the discussion of noise is mostly unnecessary. In the Kansas City area in the USA, there are dozens of underground businesses, and space is measured in acres (or hectares)! Most are storage, but manufacturing, sound recording, office, library, archiving, maintenance, and other uses also exist. The first company around here to go underground was Brunson Instruments over 50 years ago. They used existing man-made caves in the local limestone strata, and found that costs for calibrating their equipment dropped dramatically while quality rose. I have worked in a number of these "mines", which often extend for miles under residential subdivisions, highways, businesses, amusement parks, and even rivers.

The best approach is to make use of what the local environment permits. What is done here is a good example of that.

Regards--John M.

Thanx for the encouragement. I will dream on...

If you are still considering building your project, I would encourage you to look into ICF construction. If you wanted help on planning visit www.greenbuildingtalk.com. There are many people who have used insulated concrete forms for their basements, and many experts on the green building forum that would give advice for your project.

Good Luck, Jamie

Yes but the concrete absorbs Co2 for the first severn years of its life.

For the rain water , to my opinion it would be good to check if the building has a good drainage system around. If there is a geocomposite drainage layer it can carry the water away and also the air between may decrease the sound as well.

http://geosynthetic.blogspot.com/search/label/Drainage

Please see above link.