floor pit construction

[KarlsGarage]

I built (scabbed together) a shop years ago and poured the floor with a pit in it. It was about 8 x 4 and worked great for the work that I was doing. Sandy ground in a mild climate so didn't have water problems. Only downsides were ease of access to it (short ladder), a friend that almost stepped into it, and spiders. Upsides, it worked great, was way cheaper than a lift, I could cover it and it didn't take any room up in the shop.
If I could afford either option now, I would go with a lift...

 

[russlaferrera]

As stated in my earlier post. Safety is an issue. But lets put that aside. Lets look at the pro and cons.

How deep? People are different heights.

How wide? Must accommodate different vehicle widths. Can you get around a trans jack when R&R a trans?

Tool accessibility. It is a problem getting need tools you forgot.

Limited use. Can not do much mechanical work on FWD vehicles , brake jobs, struts, tires.

Cost. It costs the same for a lift as a pit.

A pit requires no set-up. Just drive over.

Height & width. If you are tall, crouch. If you are short, build a sub floor. If you are fat...don't do transmissions.

Just one statement on safety. Vehicles do fall off lifts and vehicles do fall into pits. So IMO that's moot.

 

[Falcon67]

I think a pit is the pits, but around here it might come in handy when an F5 tornado is stripping your house off the foundation. Maybe.

I would get some trusses designed to provide some increased ceiling height. Should be able to get 9'+ in at least some spots or in the middle of one end.

Another idea is a small space say 20~24 wide would be to go clear span on one end for about 12'. Get a lift with a caster kit. Load the vehicle on the lift, spin the lift sideways (90 degrees) into the clear span area, lift away.

 

[slghmmr88]

Go ahead and build your pit and just call it a storm shelter, here is a link to a company that makes them especially for garage floors. To make everyone happy go ahead and ventilate keep it covered when not in use. http://www.flatsafe.com/

 

[c39er]

I love my pit! Drain/phone/fresh air/carpet and beer/ tool pockets. Used it for 20 years.

 

[bazzateer]

there are easier ways to get around height restrictions...you can frame a vaulted roof to gain enough to get the car lifted high enough to work on.

Not if you're restricted to a max building height of 2.5m.

 

[walrus]

I love my pit! Drain/phone/fresh air/carpet and beer/ tool pockets. Used it for 20 years.

Nice pit. Do you have enough ventilation to keep fumes from building up in there.? Otherwise the NEC would frown on the electrical in there

 

[nehog]

...
A pit requires no set-up. Just drive over.
...

A pit *must* be covered when not in use, and recovered after use. Not covering would be considered negligence and leave you open to a liability should anyone (even yourself) fall into it when it is left uncovered.

This factor alone was a killer for my idea of a pit, moving covering on and off the pit would be a lot of work. Not worth it--considering that it takes me a minute or two to set the lift arms.

 

[c39er]

Nice pit. Do you have enough ventilation to keep fumes from building up in there.? Otherwise the NEC would frown on the electrical in there

A lot of things would never be done if all the rules were followed. I believe in following most all rules. My pit is used only by me. Ventilation is excellent. The county now says I (we the area people)cannot touch build on/clear 65% of our acreage properties because of the county wanting to keep natural vegitation/plant life yet I still have to pay full taxes. Things like that make some people want to not quite follow all the new stricter laws-I built my pit the way I like it. I don't let anyone near it-or the shop for fear of all the extreme dangers my shop could pose!

 

[bazzateer]

You could get killed by walking out the front door of your house, but we all still do it. It's not inherently dangerous, and neither are pits. Constructed properly, maintained properly and used properly (inc covering when not in use) they are perfectly safe.

 

[A_Pmech]

You could get killed by walking out the front door of your house, but we all still do it. It's not inherently dangerous, and neither are pits. Constructed properly, maintained properly and used properly (inc covering when not in use) they are perfectly safe.

Aye.

I have a pit and wouldn't trade it for a lift. Lifts take up too much dedicated floor space and I don't like the basic design of the standard 2-post lifts. There are too many videos of vehicles falling off of the arms for me to want to get under one. The basic flaw with vehicle lifts is that there is no positive means of engaging the lift arms to the vehicle, they rely on friction only. That may work fine for a floor jack, but I don't consider transferring that technology to a lift to have been a smart idea.

When auto and lift manufacturers develop an industry-standard jacking point which POSITIVELY ENGAGES the vehicle to the lift as the aircraft industry did many years ago AND locate those points so that the vehicle will be stable at any CG location, I'll consider buying one. One does not jack a 300,000 lb. 777 by relying on friction alone between the jacking point and the jack stand.

http://www.airliners.net/photo/China-Southern-Airlines/Boeing-777-21B/1212249/L/

Until then, I find it really hard for a 5' wide vehicle to fall on me when I'm in a 30" wide pit.




(There is a glaring safety violation in the photo, but it doesn't involve the jacks. That operation should be done in a hangar, not out on the ramp unprotected from the wind!)

 

[Falcon67]

Go ahead and build your pit and just call it a storm shelter, here is a link to a company that makes them especially for garage floors. To make everyone happy go ahead and ventilate keep it covered when not in use. http://www.flatsafe.com/

If we have money during construction, my wife would be wanting one of those. But I'm not sure you want a "safe house" area under a building that might well be laying on top of you after the storm. If the lid opened up and it came with a multi ton hydro jack to raise the lid, maybe. My first thought was trying to slide that lid open with 10,000 lbs of scrap lumber and roofing piled on it.

 

[blkhonda1991]

Not if you're restricted to a max building height of 2.5m.

i imagine a height limit of 7.5 feet is probably very rare restriction, at that point you can barely build a shed

 

[bazzateer]

i imagine a height limit of 7.5 feet is probably very rare restriction, at that point you can barely build a shed

Not at all rare. I was refused planning permission to build my garage 4m high (at the peak). This leaves me with the option of spending money I don't have on an appeal or new applications for permission or building within permitted development regulations for which planning permission is not required. These regulations state that if building within 2m of the property boundary the building must not be more than 2.5m high. See section 8 on the link:

http://www.planningportal.gov.uk/uploads/miniguides/outbuildings/outbuildings.html

My plot is 6.5m wide. To build it higher under permitted dev't would leave me with a 2.5m wide garage. I'll stick with the 6.5m wide x 10.5m long x 2.5m high thanks.

 

[ihredo4]

Would you be able to go down. I don't know the ruling but if they say 2.5 meters where does that start? Ground level. Is it possible to have the building built into a rise in the ground to keep you below the 2.5 meter yet have a floor that would be below grade at that reading? Does that make sense. Maybe you can beat them at their own game.

 

[Justanoldguy]

i imagine a height limit of 7.5 feet is probably very rare restriction, at that point you can barely build a shed

2.5m does not equate to 7.5ft.
More like 8.2ft

 

[Shadowdog500]

Does anyone know anybody thats experienced these problems? I do hear you on the falling in thing, from that point of view yeah I can see the danger. From a fuel vapour/exhaust gas point how common is this sort of accident? I guess you could always build in a cage for a canary like the old miners used to detect poisonous gas!

I know of one back in the late 80's. One of the Mechanics(weren't Techs then) at the Golden Nugget Casino's fleet service garage in AC dropped a drop light(weren't florescent then) while in the pit and started a fire. I heard he was burnt pretty bad, and burned his lungs. I worked nearby and saw the ambulances, but didn't see him.

I've been in a pit and it was ok but I would at least put in good ventilation, and have a quick exit if things go bad.

I have a lift and like it much more. If you buy a heavy duty lift that meets or exceeds ALI standards, and use it properly, I believe you are safe.


Pits aren't exactly idiot proof either:

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Chris

 

[Britwrench]

Having worked on vehicles using pits and lifts, I would never use a pit again.
With the lack of access, I would rather jack the vehicle up and use stands if a lift was not available.

 

[bazzateer]

Would you be able to go down. I don't know the ruling but if they say 2.5 meters where does that start? Ground level. Is it possible to have the building built into a rise in the ground to keep you below the 2.5 meter yet have a floor that would be below grade at that reading? Does that make sense. Maybe you can beat them at their own game.

Could be done but then I'd have all sorts of drainage problems. The rear alley is the vehicular access to the garage and is on a east/west slope with the garage door on the north side of the alley. The slightest rain turns the alley into a river, if the garage is lower than the alley it will flood. I will be putting a trench drain across the entrance but even this may not cope with the deluge we often get here.

 

[sneezer41]

Baz, mebee I didn't look deep enough but the fancy graphics called for an eave height of 2.5m and a total height of 4m, implying that you could have a sloped roof that did what you want. Not uncommon here to have a height/distance related rule

 

[bazzateer]

Baz, mebee I didn't look deep enough but the fancy graphics called for an eave height of 2.5m and a total height of 4m, implying that you could have a sloped roof that did what you want. Not uncommon here to have a height/distance related rule

That's if the walls are more than 2m from the boundary. Mine are basically on it so the total building must not exceed 2.5m. Click on 'page' 8 on the links 'interactive' bit.

 

[sberry]

You got to do what you got to do, having said that the only reason I would want a pit was regularly servicing big trucks. A hoist is one of those things there is no good way around, especially given that so much of routine work is wheels, brakes, etc. As for safety hoists are well proven and a couple of video on the internet travel far, a fool can drive into a pit too, has happened a lot of times as has falling in them. I like being able to walk under, climbing in and out would get old in a hurry.

 

[Justanoldguy]

Having worked on vehicles using pits and lifts, I would never use a pit again.
With the lack of access, I would rather jack the vehicle up and use stands if a lift was not available.

So you would rather lie on you back under the car than stand up and walk around under it..

 

[Charles (in GA)]

(There is a glaring safety violation in the photo, but it doesn't involve the jacks. That operation should be done in a hangar, not out on the ramp unprotected from the wind!)

While I'm not crazy about jacking out doors, its quite acceptable according to the maintenance manual, provided it is pointed into the wind and it doesn't exceed the specified amount. On a calm day its not an issue.

Charles

 

[Shadowdog500]

(There is a glaring safety violation in the photo, but it doesn't involve the jacks. That operation should be done in a hangar, not out on the ramp unprotected from the wind!)

What do you expect, they are in China! They are not exactly known for thier safety practices.


Chris

 

[mustangmccance]

the biggest problem I see with the op's proposal is he already has said that it is not allowed by his local code. yeah he might get away with it but if some inspector comes by when he is not expecting it during or after construction the risk is not worth it. the op is in canada so he will need to review his building codes but a low height 2 post lift could be installed as has previously been posted with an open truss design like a steel building has. you would have to check if there are restrictions in the roof slope, if not you could build a fairly steep roof which would give you better clear space inside. just a thought.