We are wanting to put a service pit in my shop, we are converting an older barn over into a shop and was wondering if anyone had any good ideas how to go about it and what to put in it. We are thinking about 50 ft long and about five feet deep, we have discussed putting pylasters [cement butress's] on the insides and outsides of the pit walls and to make the bottom inside width about 6 ft and the top opening width 3 ft. We have discussed putting H beams 12 inch by 12 inch along the top running lengthwise so we'd end up with a 4 ft wide opening and have a place to slide roller trays and also a strong place to put jacks and such and also be able to pull those beams out if I needed to drop in something wider into the pit for any reason. We are planning on having in floor heat in the pit floor, venalation with a small fan that comes on with the lights, lights, air hose pressure, waste oil evac system to blow waste oil out and into a storage tank outside, basic tools and wrenches down in the pit, steps on both ends and pvc lines buried under the cement if we think of anything later we need to run to it. We've tossed around the idea of hose reels with meters to dispense oils and lubes but haven't made any definate plans on that yet. Any other ideas or designs. I am tired of trying to crawl under trucks and trailers to service and do repair and also service dozers and change oil and have wanted a pit for decades now and even though some have tried to discourage me from doing it it's going to happen, if anybody has any other things we missed or need to put in that are handy or have saved them grief let me know, I'm open to any idea possible, also if anyone has any idea for a jack that would lower and raise with rollers on it so we can put in and take transmissions out of trucks I'd like to hear about those as well, I need to take out a few transmissions and put in new ones after this is done, we need to be able to lift it up to the transmission, hold it, lower it down low enough into the pit and roll it out from under the truck and reverse the process to put in new again, it needs to work for belly pans on dozers as well. Thanks in advance for any imput
I've thought about a pit too ...I'm not sure about your part of the world but I've been told by building codes you must a ventalation system of some sort ..One thing i thought was to design it like an old front end alignment rack where you could have all your tools and work bench down there ..A pit would be nice ..easy on us midlife guys ba ha ..
Weather you're subject to code regulations or not I think you want more than a small fan for ventilation. There are a lot of legal safe pits and I think the ventilation sizing is critical to be safe. Great idea but someone sometime will manage to drive into it.
I had a pit at one place I worked years ago. It worked good for trucks but you really couldn't do anything with equipment. One thing you didn't mention was a sump pump system. Water still flows down hill and pits always give me that down hill feeling
We already have a drain line up to the building and plan on putting the drains into it along with the drain in the building, we want a sump style where you get a foot or so in it before it runs out the drain so if we had a spill we could clean it out first, the same style as we are planning in the floor drains and we plan on putting tile under the cement as well along with around the building.
We put a pit in an existing shop about 5 years ago. Have lights resesed into the wall when we poured it and have a oil tank that runs on a track and just run it to one end and plug in a QD hose and turn on a pump and it dumps into an outside storage tank. I will try and rember to take some pics monday. Works great for everything from a pickup to an excavator.
Im jumping in on this a little bit late, but better late then never. My background is trucks and i have worked in a couple of shops with pits. I love them. I see you were thinking of about 5'. I would strongly urge you go to lower. 6-7' if you can do it. One shop had a 6' pit that had grating about 6" off the bottom that was the floor. This let the sludge, grease and oil fall through the grate so you were not walking in it. Another place had a pit that was only 5' and it was a pain in the head to work in. Im 6' and i had to be very careful as to not whack my head off of a diff or a brake pot. Even if i dident manage to hit my head, i still had to stoop over more often then not to work. It was really uncomfortable. When building i would go low as possible. It's easy to make something to stand on in the pit to raise yourself up. But you can only get as low as the pit is poured.
Many years ago I built one out doosrs with about two feet above ground, I did not know just how helpful that was to work on wheels and stuff with out bending over.
I worked at a truck stop shop for awhile and we had angle iron on the sides of the pit to prevent drivers from driving into it but it was amazing how many still tried.
We've gotten back to work on our project again and been looking at other pits and asking even more questions, now more confused than before, some are saying to make it straight walled on the inside and only 4 feet wide and others are saying to make it 6 feet wide and have the opening 3-4 feet wide on top. I've seen several pits with the grid deck flooring in them and they are deeper say around 8 ft with a raised floor, I understand how they work and they are nice if I went with that design I'd have to have a sump pump that pumped the water up into the out going drain, which would be at a higher elevation, not totally out of the question but would add a lot of expense and my cement guys are trying to talk me out of it. The design most of my crew and cement guys like is 4 ft wide and straight walled on the inside and pilasters on the outside and go about 6 ft deep, but this gives no room for tools or anything else as far as tools or an oil evac system or lights for that matter down there and out of the way. We discussed putting flush mount lights into the walls but have no experience with them and was wondering how much light they threw off and how many would be needed and also how to update them in years to come if we didn't like them, they would be rather permanent if cemented in. We've talked about putting a metal stairs on each end and that would be a place to put the evac system in, under the stairs on one end and having tools in trays that slide under the stair steps as an idea, any others have any other ideas as to how to have stuff handy but hidden and out of the way and not cluttering up the pit work area all the time. Thanks for the replies.
Heres some pics of how we did our pit (not quite finished). We put C section steel along the sides so we can fit a rolling jack in there, to get the recesses for the lights we mounted some triangle shaped boards on the concrete shutters and had electrical conduit running between them Ours is only 3' 4" wide to handle cars as well and only 5' 6" deep, cold have gone deeper but its good for tractors which it mainly gets used for.
Hsv127, thanks for the pictures, it helps me to understand how you did it, how thick is the concrete in the pit walls and floor around the pit?
Most of the pits in my area of Indiana have been filled in thanks to OSHA. Guys all are using wheel lifts now.
guess i better not tell them we have one. Fire marshal has ben hear a few times and no one has said anything. Jason
where you at in Coatesville? I know a few people out that way.
The walls of the pit were about 7" except for around the recessed bits for the lights they were about 15", the shop floor is 7" thick. Hope this helps.
Yes it does thanks for the replies and the info HSV127
im just south of 36 in heritage lake. We made a oil drain pan that rides the full length of the pit on a rail and has a qdc that you can hook up when its full and a diafram pump pumps it to a tank outside need to figure out how to post a pic. Jason
trying to figure this pic thing http://picasaweb.google.com/Gweldin...hkey=Gv1sRgCO-hqfrd66WcaQ#5559877799650829858
My guess is the ceiling is low and the only way to get the excavator boom low enough to clear and still ground the bucket was to put it in the pit. Or were you referring to the broke down Ford beside it?
Nowing75, nice picture, how did you do your lights in the pit are they recessed into the walls and are the walls straight up and down inside or is it slightly wider at the bottom of the pit, also how deep is your pit and what do you have for steps or ladder system to get into it? Thanks for taking the time to post the picture and respond.
I just had the boom in the pit so we could grease it. I will have to check how deep it is we went deeper then the boss had wanted but im glade we did because for pickups its almost not deep enough. The lights are resesed in the wall we put foam in the form to make a block out when we pored it We made stairs at eather end that pivot up to clean the floor and you can just un pin if you need them out. It has a sump pit at one end and air along the wall. If we were to do it again i would want a resess in the wall for the tool box.
Here are a few pics of my Buddie's Pit. It has 12" beams around the top w/ a few pull points, lights, electric, heat, sump pump, and air. About 4 1/2' deep, very nice!!!
Hi Randy. We too are in Iowa and plan to set up an equipment pit for Dozers and Trucks. We have been advised by a pit owner in Solon that he made his pit too low since you are usually working on a truck or crawler underside that is already 2 ft high. The pit for Trolleys in Mount Pleasant Trolley Barn is too low and you always have to stand on a box, which means you cannot walk or reach very far. It also requires a sump pit and pump to get rid of water. The Oil and grease from the century old cars pollutes the floor and a lot of oil dry is used and gets in the sump pit. That pit is 8 foot wide with supports and standard rail on beams under the rail on which to hit your head. The Cars weigh at least 10 ton and up to 30 ton. How deep did you go with your pit?
Cad7, to give you a quick and simple answer, mine is too shallow, only six feet deep, I'd go much deeper next time around, if your in Iowa, I don't care where you are located, and even if its only a foot deep, you need drainage and a sump pump, tile lines or whatever it takes to get rid of water not really from within the pit, but under and around the pit itself. I've seen far too many pits that have no means to get rid of water and are a glorified fishless water bowls that nobody can use. I made mine to fit me, or so I thought, I'm slightly over six feet tall, and we use planks to cover the pit when not in use, which is very seldom, I have a ledge cemented into the top of the pit, so planks can fit in and be level with the rest of the shop floor. This was a great idea but we find we use the planks recessed into the top ledge to hold drain pans, jacks, blocks and whatever, then I have to bend over to clear those to get around in the pit itself. Pits are designed to work on stuff standing up, never complain about having to stand on anything to reach comfortably what you need to work on, the issue you'll have with a shallow pit and your too tall and have to bend over to work on anything or get down on your knee's to work on things if your too tall when standing up. Not sure this makes sense or not, but you'll find even working on machines that have two feet of ground clearance or more, its better to need to stand on something to reach, than too tall to work on much of anything. I'd measure your needs starting with your height, then plan on having planks, blocks or whatever spread across the top of the pit, never consider the height of the machines your working on as your gauge to measure off of, if that makes sense. Myself I'd want at least a foot over my head height to the top of the floor beside the pit, or ground level outside the pit itself, that way I can walk anywhere in the pit without bending over to clear blocks and low equipment. Ideally I'd have a mesh decking to stand on, that had steps built into it in small increments so I can walk up it to get the ideal reach I need to work on things comfortably. There are dozens of ways to design a pit, for dozens of applications, I'm not sure what exactly your planning on doing over your pit or what you have to work on per say, but don't go too shallow in depth is my advice, but I hate bending over and knocking my head on things. Not sure I helped at all, but to me, deeper is better than too shallow, I've wished mine was much deeper at times, never yet wished it was shallower, take it for what its worth.
One of the reasons pits have fallen out of use is that they can collect both flammable vapors, toxic vapor and gases and liquids of all type. So an interlocked explosion proof blower is needed, as well as explosion proof lights and tools. Then to prevent it from being considered a confined space, easy access in and out with a vehicle in place. The quick change oil places by making the pit part of a complete floor with stairways, blowers interlocked with the lights and other such features. And all the sumpage/drainage has go to a water/oil separator before being discharged. It can be done, but not easily or cheaply. Howard
I do like the pits I've seen with side exit stairs, of course that means there's a bridge header you have to walk under but at least you can't easily get trapped under something, or have issues with long trucks positioning over the access points. a sled or two on rollers to hold drain pans, tools, parts are pretty cool idea too.
hetkind, your right to a certain extent, depending on the state's laws, what insurance companies deem and how or what your working on or plan to work on over the pit, with farm, semi's, trailers or construction equipment or even vehicles for that matter, my insurance company didn't have a set criteria to go by, they claimed there was no added risk or threat, it never affected my insurance at all, and ironically no ventilation was required. I didn't hard wire lights in, so no code was needed for that, basically nobody I talked to liked any that were hard wired in, they never shined where you needed light anyhow, glad now I didn't hard wire any in, my opinion is, they'd be completely worthless at best if I had done it. I wasn't required to have ventilation in the pit either, but I did put in a natural draft ventilation line where I could put in a fan if needed, turns out I never will, I have far too much the way it is and have to tape over the ventilation lines to partially shut them down, full open and you'd never get a cigarette lighter to light with the suction in the pit. I had an insurance audit done before I put in a pit, basically someone from the insurance company comes out, does a sit down with you and you hash over the idea, the explanation I got from them was, if your concerned about toxic fumes and dying in the pit, you've got far more problems than just the service pit to worry about, most likely you'd be dead on the shop floor anyhow, long before the pit was an issue. Now if you work on or plan to work on painting equipment or trucks carrying chemicals, then maybe, but for my full line of equipment I own, which they went over piece by piece and asked what others I planned on buying or working on, nothing ever registered as a possible suspect for an issue. Now that said, I also don't run machines in the shop hours on end while in the pit either, nor in the shop without a hood on them, so it was a mute point is how it was explained to me and still feel to this day. I'd been told by dozens of people what a bad idea it was to put in a pit, said I'd die like everyone else who's ever had one, so I asked both the state and my insurance company for data of deaths or injuries sustained while working in a service pit, both had nothing to back it up for "my" type of work I'd be performing, other types they had some, and most everyone was doing something they shouldn't be doing when a problem came up to cause the statistics. My insurance company told me, it was about like dropping a dozer on yourself and dying from that cause, it happened on the shop floor, thus all shop floors should be banned kind of thinking, we'll forget the fact in order to actually drop a dozer on yourself, maybe you were not doing something right in the first place and maybe you were not where you should have been that was safe, but blame it on the shop floor, it was the cause, and that was a direct quote from an insurance company rep I spoke with and his analogy of the thinking of some as to not put in a service pit. Before ever putting one in, I'd contact both the state and insurance company and even the city if you live in a city and ask about requirements or codes you need to know about, and get everything up front first, then proceed. Your state, location, insurance, everything might be different, same goes for what your working on, but for me, none of those issues applied or were a factor, now if you consider safety as the issue, I'd take the pit any day over working under a machine blocked up, or laying on a creeper on the shop floor, but that's just me. As for not being able to get out from under whatever is parked on the pit, chances are if you drive the piece over the pit, and can't get out, there's a good chance your not going to get into the pit in the first place due the machine being parked in the way. Now if you have someone else drive the machine over the pit and your in it, my question is, would you lay on the shop floor as someone drove the machine over you to save crawling under it?? I'm not really sure how anyone gets so much contaminates in the sump, doesn't anyone use containers to collect used oil they are draining out of the machine and just dump it in the pit floor?? As for washing off machines, do you guys collect all the wash water outside the shop and filter that?? If this is such a big issue, pump the sump water outside on the wash bay floor and do the same thing as you do with the wash water, which is in most case's let it run or collect in a huge wash vat to be pumped out and dumped via a septic service is what is done around here, then run into a waste treatment facility that way. I'm not sure how most do it, but we generally wash the stuff off first before putting it over a pit, collect waste oil as we go, and when done, maybe some is spilled and we use dirt or floor dry to clean it up, no different than the shop floor, where does all this contaminates come from?? And all toxic fumes, someone has to explain this to me, since neither the state or my insurance company had any hard data as to deaths or injuries that were caused by the use of a service pit, ironically nobody that warned me, had any name or incident either that stated specifically the pit was the cause when used properly, some whom had total brain farts, but they'd have died even without the pit involved.
Randy did you have any pictures of your pit?
You have some excellent points there. I am concerned about carbon monoxide from a running engine dropping into the pit (C0 tends to sink), and OSHA has this funky confined space standard that is concerned about things like that, 29 CFR 1910.146. I have investigated more than one confined space fatality, and pulled guys out of trenches welding pipe when the CO from the welder sunk into the trench. Once you have a stairway out, it is no longer a confined space and OSHA can't cite. Since I tend to work on too many gasoline powered vehicles and dropping a fuel tank to change a pump often results in a spill and those vapors also sink. One mechanic working in a shop by himself is one thing, but three or four separate jobs going on can make things interesting. I have come out of under a truck or bus coughing numerous times when some other idiot would fire up a Detroit 8V71 pointing towards me... But I am not telling you anything that you don't already know. As lifts get cheaper, pits become less attractive. But they have their place. I have seem some wonderful photos of the two post bolt on lifts tipping in the most entertaining ways. Howard
Daro, what do you want pictures of per say, I could take some if you say what your wanting a view of, there's not much to it, just an open topped box with a lip along the top edge for planks to recess into. I ran the wiring, air lines and in floor heat lines under the concrete in pvc lines from the shop walls to the pit itself before the cement shop floor was poured. I have the main electrical panel and water manifold on one end attached to the pit walls. I ran pvc lines poured in the pit walls for the wiring and outlet boxes along one wall, all the ventilation tubes are at the bottom in three or four spots along one length of wall for sucking out stale air.
Actually CO is almost zero (neutral) buoyancy, relative density 0.96716, one of the few gases that DOES NOT sink....* CO2 sinks but it would take a ton of it to poison anybody and with all the air motion from open doors and wind, engine fans, etc. it would be unlikely. One hazard for sure is flammable vapors such as gasoline and propane, and brake cleaner, they sink readily and will fill up spaces and many explosions and fires have resulted. *HAHA MICEN was what we were taught in school. The list of gases lighter or equal to air. Hydrogen Ammonia Helium Acetylene Methane Illuminating gases Ethylene and Nitrogen. That's it, all else is heavier.
There's always a flip side... one time I was working in a shop that was a former bus barn, nice facility. Came back from lunch one day to find the guys walking around under a full size six wheel drive artic that they had proudly hoisted skyward on a two ram air over hydraulic bus hoist. After checking it over and giving them a pat on the back for being creative I did make a rule that they not hoist anything else without getting clearance from me first, lol. If it might, they will!
We have one. Full truck and trailer length. 4'x 6'. Metal sliding grates on top. Got grates in the bottom. has a secondary set of rails for the drain pan. Love it as I go on the weekends to change my oil. No mess, no clean up, and no bending over!
I'm thinking about a pit for my next shop. I want to install ventilation for safety, so for removing heavier than air fumes and vapors from the floor of the pit, what is best? Should you suck air out of the bottom of the pit which may cause low laying fumes or vapors on the shop floor to be drawn into the pit. Or should you blow fresh air into the pit, or a combination of both?
Dunno what the "right" answer is, but to my thinking you would be best off with a fresh air source at one end and air suction at the other?
I'd talk with a ventilation person, I'd think before you get concerned with that, you'd also want to factor in other things, like shop fans, air scrubbers/heat exchangers, forced air heaters, where your air inlets are and the list is endless, otherwise even with a suction fan pulling air out of the pit, those might allow air into the pit and end up being air inlets instead of outlets. Just something to ponder over and ask question about to your local ventilation person.
I'd blow air in from outside the pit because then your blower does not have to be explosion proof.
Consider this, I am in Northern Ontario Ca. (Canada, not California ) It is -33 deg C this evening so cold air from outside is not the simple answer for me. How do you blow in air and be sure the heavier than air fumes and vapors are removed.I have talked to many people about this and the consensus so far is not to build a pit. I am hoping to hear from anyone who lives in a cold climate who has come up with a solution to this issue. I am thinking some sort of air in and air out system for the pit is required. Obviously any air pumped outside or fresh air pumped in will add to the heating bill. Has anyone seen a good solution to this?
It ain't rocket science; if you have some kind of fan circulating air down there in one end it should clear out any small spills within a couple of minutes. If you can feel any kind of breeze it should be OK. But if you have to satisfy some bureaucratic regulations then you may have to have things designed and stamped, etc.
Heat exchanger
Yeah, I've already thought about that. You still lose heat but it's better than drawing in cold outside air.
Let's take a look at the ventilation issue...we need to have a floor level LOCAL exhaust of the pit to remove vapor, fumes and gases that settle. But we don't need much, probably less than 10 cubic feet a minute, because the source of contaminants is either from evaporation of a liquid, like gasoline or diesel fuel OR from a heavier than air gas dropping into the pit like exhaust gases/fumes. But for ever cubic foot of air we remove, we need to replace with conditioned make up air, also at the same less than 10 cubic feet per minute rate, and want that placed at the breathing zone of the worker. So a push pull system where we inject conditioned air for worker comfort at the top of the pit and pull air with a possible contaminant at the bottom of the pit. At those small amounts the cost is very reasonable. Howard
I've got a pit, which most know, I'm thinking your splitting hairs on your concern, for any gas, vapor or anything to settle to the lowest point, takes time, its not like spilling water and watching it run the lowest point, gas takes far longer to accumulate in the lowest point of any shop, unless your fogging the shop in such massive quantities of poisonous gas such as when an old Detroit is puking out massive amount of smoke and fumes from unburned diesel. If your running a Detroit or putting in massive quantities of poisonous gas of another source, the pit is the least of your issues. Aside from that, it takes far longer than just a few minutes for gas to accumulate, like a half hour or hours, with even the slightest air movement in the pit, your circulating the air and no issues of excess gas pocket accumulation should occur. Now unless you plan on circulating the air outside the shop as in a heat exchanger/scrubber/filtration system of some sort, your concern about a pit is what?? your only circulating the air that is already in the shop, if its toxic, I'm not wanting to bash anyone's concerns, but your still breathing the same air where is the concern with the pit come into play?? you've got far larger issues than the pit, as the insurance company rep explained to me, and which made sense to me and still does. Not wanting to be negative, but the issue with putting air into one end of the pit, and a fan in the other, depending on how large and long your pit is and where the vents are located, why would the air be drawn from one end, when it can suck in from the open top of the pit, far closer to the exhaust fan or suction tube?? You need air inlets and exhaust along the pit length, but before anyone can tell you anything about where or how, you need to assess your dimensions and how air flows and where it will flow, every one is different. Now let me ask a question here, since I've heard this a couple hundred times before about pit gas's, when your about to crawl under a machine on a creeper, where are your fans located?? how will you survive a gas issue, how do you plan to get out in case you'd spill some gasoline, after all, your at the lowest location in the shop at that point, what was your plan before you crawled under the machine, the air there is stagnant and toxic vapors could be accumulated waiting to kill you?? If you have a loft in your shop and your on the main floor, basically your in a pit of sorts, what's your plan then to survive and circulate the air so in case of gas vapors it won't kill you, do you have fans blowing on your constantly anywhere in the shop. Not sure if you have a house with a basement or not or an attached garage, but if you did, are you concerned with poisonous gas's in your basement every time you start your car or pickup and leave, how about coming back home hours later and entering your home?? Next question is, even if you don't have this scenario how many do you hear dying each year or being injured and hospitalized every year in the world from this issue?? If you were to walk into your shop, and feel sick, or see a fog or low hanging haze near your shop floor, what would you do, close the doors and stay inside or open all the doors and vent the fumes as safely as possible?? A pit isn't the issue, it how you handle the situation your given at any point in time is. Yes circulation is important, air flows are really important, but its not just for the pit, its for the entire shop and work environment and for that you need someone who's up on those things to walk you through them on every aspect of the planned project. Now if you don't, don't get too shook up, you'll get to later on, you'll have condensation issues, frozen doors you can't open, same as windows you can't see out or open and it'll eventually get done, I'd suggest doing it up front, just keep in mind while doing it, as you add machines, shelves, tools, equipment in the shop being worked on and everything else, air flows change. You only need a small amount of air movement to circulate gas's and fumes, if they are indeed toxic, you need to vent them somehow, not really sure yet how anyone gets those toxic of fumes into the shop and are ever willing to keep them in by not opening doors, windows or vents and turn on massive fans to blow it all out, but I'm told its been done before and usually where all the statistics come from on legal or deadly accidents. When we bring machines in, we have a large fan sitting in the loft, keep the door open and turn it on, vent all the smoke and when its clear and fine, we shut the doors back up, can't say the pit was ever an issue or concern and the cost of heating never entered into the equation once at those times. As for gas vapors or any other vapors, whether its in the pit, shop floor or anywhere else, the doors come open, every fan in the shop comes on and the whole shop is ventilated massively, heating is the last of my concern, the pit is far below that on the list. We do a lot of welding and fabricating in the shop, I need a heat exchanger but have not put one in yet, I have natural draft ventilation in the pit, never been concerned yet with working in it, when someone is next to the pit welding, does that mean mine is perfect, absolutely not, but if I can see, smell or taste something out of the ordinary, fans come on and it doesn't matter where I'm standing in the shop, in the pit or right next to the welder being run. The last issue to keep in mind is this, your not laying in the pit floor, your usually standing upright, or at shop floor height or above, its not really any different than laying on the main shop floor where your head and nose are at, your not sucking up and breathing vapors laying on the pit floor unless your laying there unconscious for a long period of time. Most don't weld on or near the pit floor, when I'm welding in the pit, its usually on a machine above the pit or above the shop floor in essence, all you need is a small amount of air movement to circulate any air in the pit, is adequate to never have issues, the only better way is use common sense, just like anywhere else in the shop or with any situation. Not really a rant or downgrading anyone's concerns, heath is everyone's concern, just keep everything in perspective and don't let some peoples hysteria deter you from putting in a pit, common sense is still your best friend no matter the issue.
We have had a pit in our shop for 20 years. There is a 4 inch pvc line from 2 inches off the pit floor , under shop floor and up the wall to a 24 inch barn fan. The fan is boxed in with a trap door .When door is open fan draws exhaust from shop, door closed draws from pit. Fan has only been used for pit maybe dozen times in all these years. We have a 4 foot florescent light in wall and an electrical outlet for sump pump. Never had an issue with the pit. We do all our own fleet repairs , welding and fabrication. In our sewer side of the business we deal with confined space entry on a constant basis. As Randy88 has said, put things in perspective, use common sense and drop the doom and gloom. Our new shop will have longer pit to service tractor trailer units. Only change is 6 inch pipe for exhaust as per building inspectors request.
Daro, you wanted some photo's of the pit, finally got some to come up on here, not in the right order, but took me most of the day, much easier to do the whole pit than post photo's. The first photo is of the shop floor going over the pit walls, if you look at the end plank, you can see a couple two by's screwed together, when the forms get pulled, those are the recess for the planks to lay in, level with the shop floor. The forms are made up of two planks screwed together for the shop floor over the pit walls, the fist plank is red headed into the pit wall and the second is held in place with the 2x4's that are screwed on vertically. After the shop floor is done, we pulled the top plank off and left the bottom plank in place, that's where we screwed our air pipe air line to the length of the pit, it also serves as second place to put a plank across to have a drain pan holder lower into the pit. The second photo is of the footing for the pit and pilasters, the tube sticking up is for the sump pump, below the footing about two feet i the length of the pit we hand dug in, one line in the center dumps into the pit sump, and two more one on each side the footings also hook up to the center line. On top of that and once the pit is poured, we ran another run of tile just a couple inches below the top of the footing. Then every two feet in height we ran another tile line for a total of four layers along the pit walls and below the floor, then the entire shop is pattern tiled every five- seven feet of width, and along the walls of the shop we have two layers of tile lines, one just below the shop floor and the other hand dug in near the footing of the building itself. The third photo is of the finished shop floor on the left side of the photo, the right side of the shop floor left to do yet, the rebar's from the vertical's on the pit, are bent over and tied into the floor rebar's. The last photo is of the forms coming off and before any tile or backfilling is done. Air suction lines are also run near the footing's, just above the tile line and is going into the pit walls in about four places and go up the wall and into the attic and out the end of the building. All the rest of the lines under the shop floor to the pit are not in yet and I'm not sure I have photo's of those. Once the pit was done, we laid insulation board in the pit, put in floor heat lines, and rebar and cemented in about 4 inches of concrete in the pit floor. We originally planned on going about two feet deeper with the pit, but as we dug it, the dirt kept collapsing and we got concerned the building walls would collapse in, so we shallowed it up, nothing caused problems. It took about two hours to dig for the pit, when we got to the end, we had two feet of water in the hole, took two sump pumps to keep the water pumped out so we could work. As for how many feet of tile, I recall about 2500 feet of dual walled tile under the shop floor and around the pit. The summer we did the pit, we were having a drought and it hadn't rained in a couple months enough to worry about, as soon as we got it done and the inside cemented, it started to rain a lot that fall, for a few months the sump never shut off to keep the water pumped away. The sump tube goes down about 8-9 feet below the footing level of the pit. Not sure if it helps at all or what you wanted, if you want something specific you'll have to ask and I'll see what I can do to find photo's for you.
Very impressive Randy, should last a lifetime. How do you think something like this would work? Bearing in mind we don't have issues with subsoil water or freezing temps. Cheers, Greg http://jacobprecast.com.au/Vehicle%20Service%20Pits.html
I don't know how thick the walls are for that, or what the dimensions are, but I do know of one guy that used a new septic tank without the lid for his pit, the walls were not very thick and it also wasn't rebarred very heavy, those only use mesh in them, for a septic they work fine, when he backed something over it, his walls buckled and it collapsed. I'm not sure I'd want one unless you had pilasters installed in the walls to help give it support, but it depends on what you plan on driving over it all the time with, the more weight you have over it, the more inward force you have on the pit walls. Its not uncommon for me to put two 70-80k machines over the pit at one time end to end and my floor is tied to the pilasters and pit walls, the shop floor is 8 or so inches thick, with two levels of rebar in it, the pit walls are 10 inches thick and pilasters are far thicker still, can't recall off the top of my head how thick but 16 inches rings a bell. I don't know anything about your ground, the wetter it is, the thicker you need to go on concrete, the heavier the machinery the thicker you need to go so the concrete won't crack or buckle. I was told by many that I went far overkill on everything, the concrete guys in the area told me maybe 6-8 inches for the walls and 5 inches for the shop floor would be fine and when I sat down and did the math, the overall cost to go far thicker was minimal and the strength was far greater and I told everyone, someday someone can break it all out and cuss every moment of doing it, but until then, it wasn't going anywhere or cause me a moments grief no matter what I put over it, I planned on doing it once was all. I think we also used six bag mix on most everything, not four bag mix, and I also hunted up a concrete provider that actually put in what I ordered, no fly ash, not 3 and a half bag mix instead of four, or five bag mix instead of six type thing. Before putting anything in to use as a pit, know how its build, what materials they put in for reinforcing and also how much, you still need a footing to set it on so it won't sink or be shoved into the ground deeper, I think my footing is two feet wider than the pit itself and a foot thick with a lot of rebar in it, like on six inch square's and two layers of them staggered. If your ground isn't very wet, that also plays into the equation, you don't need as much footing thickness or wall thickness but with anything over 15 foot I'd still want at least one pilaster on each side, those don't have to be very wide the shorter the pit is, but if you noticed the pilasters on one side of the pit are longer than the other, I was up against the building foundation and could only dig back so far on one side, so those are shorter, the other side wasn't an issue, I'm thinking the shorter one's are also thicker in width as well to compensate for the length of them. Queenslander, since I have idea of your area, climate or anything else, I'd suggest you go around and look in your area at pits, ask how they were done, ask what they drive over them with and compare it to you and what you plan on doing with it, and put over it for machines, that way you can tell if there are bows, cracks or whatever in the walls, floor and go from there ask questions to those local to you, most are more than willing to chat and tell you what they wished they'd have done differently or what they'd have changed. In my area, there are plenty of farmers dump pits for grain to look at, building walls for two story buildings and also pits to look at, not only the service pits, but also manure pits of every size shape and form. I just asked a lot of questions as to how others did it and then guessed from there. But I can tell you this much, the work is the same no matter how you do it, the material cost is minimal to go far thicker and stronger. Best of luck
Randy thanks for the pics I'm still in planing stage so the info will help.
Manure pits and service pits have different loads on them. A full manure pit has almost no side...And you can do virtually a static design load with FS on the pits since there is no dynamic load. Howard
When full and with ground around them your absolutely correct, when empty there is tremendous loads on them depending on how deep the pit is, when a pit is full and is sitting on top of the ground there is considerable loads to factor in to keep them from blowing out, like the several million gallon pit did near me two years ago, took out a road when it went, a couple buildings and killed a bunch of animals as they drowned, luckily nobody was killed in the ordeal, good thing experts designed it and the farmer wasn't held liable for it blowing or any of the millions in damage it did. Then it depends on how close the pumping equipment gets to the edge of the pit, like one did when the tractor and triple axle tanker collapsed the sides of the pit and the whole thing fell in, guess nobody figured that scenario into the strength of the pit walls, then there are few that the operators had a brain fart and drove the skid steer into the pit, good thing the new skid steer already had the cab door broken out, or else the operator might have gotten trapped inside and drowned, this way he could swim to the surface of the pit and someone pulled him to safety, course the skid steer didn't fare too well, I was told they had to pump the pit a week or so later and went in and fished it out, was also told warranty didn't cover that one, who knew right?? But the absolute best one ever was when a neighbor built his, and when it was done going through the final inspection and it failed miserably, the reason for its failure to pass the inspection was...................................get this the inspector even wrote it down, I got to see the inspection forms personally or I'd have never believed it..................................the vertical rebar's were set in the walls upside down and the wrong end stuck up out of the pit walls, to be torched off later?? At first the owner thought it was a joke, turns out he was wrong the idiot was dead serious, which brought about the discussion of how to determine which end of a stick of rebar was the correct end to put down and which end goes up?? Well after a few days of discussion and the failed inspection with not one but two inspectors, the head of the local government office came out to save the day........................he had to call the main office in the state and have a fourth inspector sent out who apologized profusely to both the farmer and contractor for any misunderstanding and inconvenience the first three had caused. So for future reference, to determine the strength of the wall in question, one needs to know that all the vertical rebar's are put in the correct way, those that are put in upside down weaken the wall and that was a direct quote from three inspectors, I wrote it down so I'd never forget it, and some think life itself can't be entertaining, it helps to have inspectors in the mix, there are days you get to learn a lot.
drainage and dewatering, with proper treatment is key...leachate is a terrible problem not only is silage or manure pits, but once you start building radioactive material waste cells the world get more complex. but shear loading is not rocket science. It is terrible when walls fail. I am far more concerned with dynamic loads than static loads due to my particular industry, Howard Howard
Randy that is to funny. The sadness in that is that those inspectors are in charge of the infrastructure that we are paying for DARO
Randy, you have a real well built pit there by the look of it.
Randy's service pit & shop remodel turned out real nice . Additions like this really shine for aging mechanics that don't need to be crawling around on hands & knees for the experience anymore . Myself approaching the age of aches & pains from this work look forward to an in ground service pit . I would like a combination style pit with traditional trench under the vehicle opening up on one end like an alignment pit for front end work . http://www.beeline-co.com/Content/A...-Ground-Design/-T-Style-Center-Pit-Model.aspx
Curious TD, what are you going to put in the T portion of the pit, tools?? You have a nice way of saying, we're getting old and fat and when laying on a creeper, tend to fall asleep instead of working. So since nobody ever told me about my very best portion of owning a pit, let me be the first to tell you guys what it is, this is something I've had to learn strictly on my own, without any help from anyone. It caught me by surprise one day shortly after we got into the shop and using it. Since it was "new" thing around the place, everyone had to try it out, which is fine, even before I got to try it out, everyone else beat me to it, which isn't surprising around here, but anyhow, when most everyone else was in the pit being totally amazed they asked me if I could hand them tools, which led to the new job of gopher, or simply translated can you "go for" this and that, at first it kind of ticked me off feeling like some kind of indentured servant and after about the third trip to go for something, it dawned on me, all I had to do was hand them tools and shut up and wait. Now this I could handle so while everyone else was being amazed by the pit, I was being amazed the work was getting done and I wasn't the one doing it per say, but then I got a promotion on my new found and created job, I located a five gallon pail, flipped it over and sat quietly and waited to be asked to go for more tools. Nobody said one word about sitting on a pail doing nothing, seems I had the most important job there was, to cater to their tool needs, after all I was doing something others considered important. So I'm going to take full credit creating a new job around my place with the creation of the service pit, its the go for guy and the job I like the most, its also the job you ask questions about if they can reach this or that, did they do this correct, didn't forget to do that, made sure they double checked this and tightened that and when on this job of the go for, nobody complains about the question asking portion, you can always say, I'm just wanting to know where your at on the job so I can have the tools you need "before" your going to need them. Now when you get good enough at this new job, like I have already, with the promotion and all, you get to thinking, something I don't do often, I've also learned some need added motivation while on the job, so I made a few calls and did something I generally don't do, called in the boy's girlfriends to visit while they worked. So in they came no questions asked, faster than lighting and twice as dangerous. So while chatting and asking questions myself, the guys needing to show like their working and doing something, I got my second promotion in a matter of weeks no less, I got the girls to go get tools for me to hand to the guys, now this took some training of sorts, but the most important part is keep the conversation moving and discussion going so nobody notices what's going on per say, and within a few weeks, on weekends now, I have someone else do the go for job and I've graduated, I get to work in the machining section of the shop and only need to monitor to make sure nobody is slacking off on my former job. Now that's the best part of owning a pit, and not one single person told me anything about it, it must be a secret of sorts, so don't tell anyone else. I've found wives can do the job, but catch on quicker as to what happened, but grandkids work too, they just take added monitoring to make sure they're doing the "go for" job correctly. I've also noticed you can hire people to do this job for you, depending on who's in the pit, you just have to put some thought to it first as to whom to hire and then work out scheduling. So before you invest in a pit, make sure your capable of managing all your newly created jobs, I'm learning it can be a stressor at times. LOL
Upgrading to led lights
Randy, very nice pit. I am in the early planning stages of a new shop. The information here is absolutely priceless!! I'm curiuos, since you are now using your pit, is there anything you would have done different on it? Say you pull a D6-7 size machine in over your pit and (for whatever reason) you end up needing/wanting to put a jack under the center of the machine and jack it up. How do you deal with that?
Bam, depending on how much of the total weight your wanting to pick up, there are several ways to do it, I know where the pilasters are at that support the pit walls, the floor is cemented onto those without any gap under them. I'd take some solid steel maybe two or three inches thick, lay a sheet down across the pit and drive the dozer over it and jack off that plate, or if the machine is wide enough to allow me a gap between the inside of the tracks and the pit wall, I'll just put a piece of steel in the lip on top of the pit wall, then lay a wider one over that that straddles the top of the pit walls, now I'm anywhere from 5 to six inches thick plate steel and jack off of that. I've had to remove transmissions after the dozer was tore apart, then I just jacked up the tracks enough to slide the steel or planks under the tracks and jack off of them. That's the reason why I poured the floor over the top of the pit walls rather than pour the walls full height first and the shop floor beside it, like many do. The way I did it, I have a wall that's 10 inches thick sitting on a footing that's a foot thick and pilaster that's also full height and there is no gap between that and the shop floor, if I'd shove anything anywhere or break anything, I'd like to see the jack that could do it, I certainly don't have anything that would take that load and bust the concrete even with a point load. The sheets we use are also at least a foot wide. If for some reason I needed to jack off something lower in the pit, I haven't done it, but I'd take a plate that was narrow enough to fit in the pit itself, and be at least six inches thick, and ideally four to six feet long and jack off the center of it, never needed this yet, but as they say its a plan in theory. To top that off, I'd take some of the weight off the machine with a use of my shop carry deck crane I can pull in right beside the machine that would be over the pit. I can't say enough how much I like the lip on the top the pit. I have already put planks over the pit in the lip, six to eight feet the length of the pit and laid a plate of steel over that, slid it in between the tracks from one end or the other and jacked off of that as well. Not sure the most weight so far I've jacked up over the pit at one time, but I have jacked up a dozer cross ways of the pit, and held it up on jacks while I did an undercarriage, worked great, the rollers were hanging over the pit and we impacted them off and new one's back on again. That dozer was over 15 ton, did the same thing with a trencher as well, pulled the roller frames off it and after I was done putting everything on new, put the track frames back on again, that machine was well over 15 ton too. I built a transmission jack that sits on the pit floor and we do transmission with that for trucks and semi's, only used it a few times and it needs to be completely redone, mainly due to needing something handier to use for that. Not sure I helped you any, but as of yet, we haven't come across anything we can't jack up or do over the pit, I really like to lower stuff down out of the machines into the pit, lay it on a wheeled creeper I built and roll it out the end, lift it out of the pit with the crane, like transmissions and torque converters if they require a lot of work to bring them out the top.
Yeah Randy , the pit would be two levels . The end (T section ) might be 3 to 4 foot deep X 14 foot wide give or take . Vehicle would roll out on the T section on H beams . This puts a lot of hard to get to items around chest high plus the wide pit allows you walk around in and outside easy when working on front or rear suspension . Would keep a tool chest and refrigerator in this area . The long narrow connecting section of the pit would be between 5 to 6 foot deep with steps going down to it . I might even add D ring's on the floor & walls as pull points for straitening out bent up stuff customers show up with . Something like that would make it a lot handier than crawling around under vehicles , I aint as tough as I used to be . :drinkup
Wow!!!!!!!!!!! I have two. Mine are 39?" wide, approximately 5' deep. I cover them with Oak plank 2-1/4" thick I cut out with a chain saw. Both had conduit poured in for lighting. Ventilation isn't a bad idea, but I don't have it. I do with portable lighting. I feel the most important features are good stairs, or ladder. They get slimy and your hands, and feet get greasy. Good climbing is essential. A shovel for speedy dry, a fire extinguisher, a bag of speedy dry, a good transmission jack, and two wooden boxes to stand on when the machine has a lot of ground clearance. I had in the now unused one cast in the concrete, cubbies to keep commonly used wrenches, grease guns, etc. The now used one lacks the space, it is missed. As for those who say you don't want one, I've stood up to do hundreds of projects, I work on a big truck, backhoe, There is a crawler parked on it now. We interrupt projects over it just long enough to service several vehicles, then another project rolls in. I would avoid a very long one. Mine are long enough to do 3/4 of a vehicle. Sometimes it is necessary to turn around. When they are too long it's easy to lose half a vehicle in the pit.
TD I've seen one similar somewhere, it only had stairs that went into the wide end sideways and the whole center section was much deeper, then on the end with the steel planks, they had a hydraulic lift that they could use to get the ideal height for working on the front ends of vehicles when in the pit itself. At the time when I looked at it, I didn't understand the reason the for the hydraulic lift, the guy who used it told me it the best part, he used it all the time, it was the only way in and out of the deeper center portion of the pit. He had a corded remote control to run the lift, so when he stood on it, he just raised and lowered it to the ideal height with the remote in his hand. That section must have been ten feet long that raised and lowered, thinking back it was pretty slick, at the time I never really paid much attention to his lift, was more interested in how the pit was built and what he would have changed if he could do it over again, his only reply was to have two more lifts, one under the vehicle in the deep portion and a second to use to get into and out of the pit instead of stairs. I've seen that lift style in another pit that serviced cars mostly, it was in a larger pit with storage in it, maybe 30 feet square and ten feet deep, then they had a portable powered lift, like an electric man lift to raise and lower where the guy worked, he could travel the length of the pit with it and get the ideal height with the touch of a button, he also had pressure evac system for waste oil and a hose and pump system for filling oil, his was even long enough he never had to climb out, he just rolled his lift ahead and raised up to put the oil in. The whole thing rode on a track system so it never got out of alignment going back and forth, his main thing was speed and efficiency of changing oil and doing repairs and servicing the bottom side of vehicles. Can't recall where that one was either, I've seen so many over the years, but some are really resourceful in getting them just the way they want them for their needs.
This is our blower set up. Never had a problem with fumes in 10 years have put 40 ton excavators over it and loaded tri axels.
If you consider using a pit versus using a lift, the truck over the pit can't fall once it is safely in place, where as, the truck on a lift has 3 or more feet to fall to the floor. While I was in the army, I saw an interesting version of an outdoor pit. I do not have a picture of it, but it was not a dug in the ground style, it was a ramp style that the trucks would run up, until it reached the level portion which the truck & trailer could easily fit on. They were made of concrete & always outdoors. Our brigade chief warrant officer (CW-4) would always put my HMMWV on that thing & condemn every U-joint on my truck every year. I will try to find a picture of it to better illustrate the main idea & difference.