Cutting a garage floor for oil / inspection bay

Don't do it...your insurace policy will most likely not cover you for accidents...and the risk is quite high...that is why you don't see "pits" much any more, except at the oil change places.

I think it would be much safer to get a lift.

 

many municipal codes apparently forbid them outright in residential structures. a buddy of mine built a house and had a pit put in. when the town inspectors came out they went ballistic

it got filled in.

doody.

 

I have an old garage that was built during the 60's that has a pit, and I love using it. If you plan it well and size it the way you want it, taking into consideration, making it long enough to get in and out with a car above it on jackstands, then do it, but I would look into the permitting requirements as stated above. Just call the local inspection department and ask someone in residential inspections whether they are permitted.

"Permit, we don't need no stinking permit."

 

Doody,
A friend of mine did the same thing...but he put the pit in after the "final inspection" was done...I still think he was crazy to do it. All it takes is one foolish friend to trip and fall in.....

 

My parents have one in their house that was built in the 60's. It is great. We have used it for 30 years. When it is not in use, we leave it covered. Never had anyone fall in yet. I will admit that the Ferrari is a little tight on it given the narrow wheel base.

 

An inspection pit can be a good compromise if you've got restricted headroom, otherwise a lift is the way to go. I have been looking into the feasibility of a pit because I don't have the headroom & raising the roof of my garage would be prohibitively expensive.

The main things I have discovered (in addition to the other comments already mentioned) are that

- a pit it should be water-proof lined otherwise groundwater will seep in.
- many gasses (like fuel vapour) will collect in a pit, then when you get the welder out --- BOOM. You can also be "overcome" by fumes !
- it should be covered with thick wooden planks when not in use
- it should include a "ladder" set into the concrete (man-hole style) so you can get in & out


I'm still thinking about it, but it's a summer job.

 

Well then just HOW are serial murders supposed to dispose of the bodies?

 

Apart from the safety aspect which I agree is potentially quite dangerous, you don't get the added advantage of being able to ''stack' a second vehicle to gain space.

 

Can someone post a pic I am having trouble picturing what this pit is like. Thanks
Erik

 

Drive to the nearest "oil change" place, and ask to look in the garage. Take a peek under one of the cars they are servicing....

There will be a guy standing in the pit under the car, draining the oil, and possibly changing the oil filter.

 

I put a pit in when I built my garage. There were no questions asked when it was inspected. There is no danger of falling in as I have steel planks that are 4" U Channel welded together and in 18" wide increments.
I can drive my car onto a plank and remove all the others for access, or center the car over th pit and have full access underneath it from front to rear.
Being that you are using an existing garage, and there will be no inspection who cares? Cut the hole and have fun. There is nothing like standing up under your car.

 

I put one in when I got my 308. I cut the concrete 6'8" long X 3'8" wide X 7' deep. Then I formed up the sides and poured them solid with concrete (with rebar reinforcing drilled into existing slab) along with the floor. The net dimentions are 6' long X 3' wide and 6' deep. There are no gasses seeping out, or water seeping in. Just an occasional spyder.

While I was digging it, my wife kept coming out to the garage and looking at the hole getting bigger and bigger and deeper and deeper. Finally just before I finished digging she asked me, "is that hole for me? I said "yep".

In all reality though, I made a cover for it that is strong enough so I can drive over and still support the car if I had to, and light enough to move (aluminum). Also I put the ladder rungs into the forms when I poured it so they are permanent.

 

"There will be a guy standing in the pit under the car, draining the oil, and possibly changing the oil filter."

I thought thats just what they told you they did and billed you for it!

Sorry for appearing so cynical, but its lifes real observations and experiences that got me this way

 

Go with the lift if at all possibly. Not only can you then change oil in your garage, but you can work on other setions of the car and store it for short periods of time on the lift. You can also make a new space whenever you need for another car to fit in the garage in bad weather or when you travel. A pit is nice, but only one dimesional. Hope this helps.

 

Aside from liability aspects of a hole in the floor to build a pit you would need to
1 Cut and remove the slab
2 Excavate the pit while making sure the earth around it doesn't collaps into it while excavating - there's no room for shoring - this will depend on the type of soil in which you are excavating.
3 Dispose of concrete and excavated material
4 Form up and place reinforcing for the new walls
5 Pour the new walls
6 Wreck the wall forms and pour the floor - concrete companies also have minimum loads which you will probably not meet (extra cost)- you wil have two deliveries - one for the walls and one for the floor With some very creatitive forming you might be able to form and pour the walls and floor in one pour???
6 Not sure how you would waterproof the outside of the concrete walls - so you need to make sure you have good positive drainage away from the garage and that the watertable is way below the pit. Remember any liquids that enter the pit will need to be bailed or pumped out.
7 Construct some type of cover to close off the pit when not in use.
I really doubt a pit could be constructed for 1/4 the price of a lift. All things being equal I like the idea of a pit but considering the amount of work and cost I would go with a lift unless there are headroom limitations that prevent.

 

Yes, in which case the task list is:

- convince wife it's a good idea to rebuild the garage
- get planning permission
- store your cars, tools, motorcycle collection, beer fridge etc. somewhere else
- get a scaffolder
- get a roofer to remove your roof
- get a builder to build-up the walls
- wait around while the builders let you down
- make some calls threatening legal action unless they come back
- get the roofers back
- get the scaffolder back
- you are now ready to buy the lift

I never manage to get past the first task

& BTW, waterproofing is straightforward, there are several processes such as. polymer injection, membranes or liquid coating used frequently for basements etc.

 

The problem with old, traditional pits is that the brickwork lining absorbs oil and crap over the years and they can become a fire and health hazard. A UK company introduced a glass fibre liner pit some years ago and I decided to invest in one when I rebuilt my garage this summer. It wasn't cheap but it really is the dog's dangly bits. It comes in a range of depths to suit your height and has a sliding seat and tool tray, resesses for lighting/power outlets and a fire extinguisher (still to be fitted in my case!).

The construction method is dig half way to New Zealand (allowing for the crypt for the mother-in-law), lower in the liner and backfill with concrete - about 4 tons in my case - having included steel reinforcing panels on each side. I was lucky 'cos we live on sand so digging was easy. If it had been clay or rock it would have been another matter.

I positioned mine so that I could work on both sides of the car at ground level with ease and with the doors open. This was only possible because the garage is 30ft x 15ft. More difficult if its only a single car width.

The blue gadget is an adjustable width centre lift jack that I picked up from a local garage that was moving and was fitting out with all new lifts at his new premises. This allows me to lift both sides of the car at once.

The cover is 225 x 63mm roofing joist timbers (9 x 2.5inch) and plenty strong enough to park a car on. Come Christmas there'll be table tennis table in there as well.

If anyone wants more info let me know.

 

Paul

That looks great can you post supplier details? Also did you have to strengthen the sides to support the jack?

Mark

 

Mark

the supplier is Mechmate in Dunstable, +44 (0)1582 670500, run by a guy called Chris Praat. Give him a call and he'll send you all the info.

Underneath where the jack sits is solid back-filled concrete, apart from the 8mm or so of glass fibre pit liner. Chris supplies a jack support beam that sits on the same locations and claims will support a 2-tonne jack or axles stands, so no problem with a normal car.

If you decide to go ahead with putting one in, send me an email and I'll give you a few tips, although Chris is pretty good with his installation info. Tamping the backfill without either under filling, or overdoing it and pushing in the sides, needs some care. The electrics need working out before you backfill as well.

If you get down this way call in and have a look.

Paul

 

LIFT PRICES - Just for reference,
Used high-end lifts with lots of service life in them are pretty affordable.
I bought a used Nusbaum 7K lb lift w/installation for $2200 about 4 years ago.
Recently another Fchat member bought a used Monarch 6K lb lift w/install for $2500. HarborFreight & others sell inexpensive lifts for O($2200 to 2500) + installation.

Ignoring the legal/liability/safety issues, if all you're doing is oil & coolant changes, a pit works well.
However, it isn't very good for 308 maintenance. After doing a lot of work on 308 engines, I'd much rathar have a lift than a pit. You spend a lot of time going between the passenger wheel well & then accessing the top of the engine. With a pit, you're still on hands & knees to access the ends of the engine (doesn't gain you anything because the wheels are still supporting the car rathar than dropping down out of the way.), then straightening up to get under the boot. Also, with a pit you're going to have to jack the car up to get the wheels off for any kind of brake, wheel bearing, or suspension work.

Admittedly, a well designed, dry, & ventilated pit is better than Jacks/Jackstands/Ramps, & may be cheaper than a lift if you're investing a fair amount of sweat equity.

 

Totally agree that a lift will beat a pit everytime. From a cost point of view, even if you dig the hole and pour the concrete yourself, the glass fibre lined pit doesn't come cheap. All up in today's US money its close to $2000 by the time you've installed lighting etc. However the (only) disadvantage of a lift is that you need garage headroom which I didn't have.

Also, if you have the space, you can park the car and put it on axle stands alongside the pit rather than over it, and stand in the pit to access the wheel well which avoids having to go on your hands and knees. Admittedly only good for one side at a time, but probably better than nothing.

 

hoist hands down
i have worked with both
1-turns a 2 car garage into a 3 car,etc etc
2-can do much much more checking,cleaning/detailing and repairs compared to a pit than u will ever imagine
3-u can sell it anytime or take it with u when u move
4- won.t have a hole to reconcrete (liability)when u move

 

Does anyone make a lift for a 9-10 foot ceiling? Most of us have low garages, or at least I do. I could go up 9 feet, but every lift I've seen is for 12 foot ceilings