Home Garage work pits - mrmender
We have just had planning permission for a extension to our house, which will include a large double garage/workshop.
I'm toying with the idea of getting the builder to dig me a work pit and get a proper manufactured, fiberglass liner fitted,
Anybody any opinions for or and against also do i need permission for one?
Home Garage work pits - L'escargot
I've got one (brick walls and concrete floor) that was put in at the same time as the property was built and the main niggle is that I have to back the car halfway out of the garage to be able to get into the pit. Ideally the pit needs to extend, say, 1m beyond one end of the car plus whatever length is needed for "stairs". I have to move my car first to expose some of the pit and then put a stepladder into the pit. I then have to lift the steps out again once I'm in the pit. The depth needed will depend on how tall you are and whether you're prepared to stoop. I guess (but only guess) that the ideal depth would be equal to 6" less than your height. Some years I get a couple of inches of water in the bottom (at the beginning of summer if we get a prolonged downpour) but this is only because of the particular soil conditions that we have. In any case a fibreglass liner should prevent this.
Home Garage work pits - rg
I mentioned the possibility of one being installed to my builder when we had extension work done some time back.

He said that the building regulations are quite tight on them, and the foundations of the house would need to be strengthened considerably.

However, if you dug your own, I guess that they wouldn't know.

Ditto L'escargot's comments - I had a basic one at my old house, and length and access is more important that at first one may realise.

Home Garage work pits - tr7v8
These are the people you want & I believe they get round the planning regs as well.

Home Garage work pits - pmh
You will need a professional surveyors comments re building regs approval, although as a rule of thumb I believe that a line at 45deg from the bottom of the existing house foundations should not intersect with the pit, although I imagine that this will depend upon the structural nature of the pit walls. Not a problem if it is built on piles.

I second all that has been said about length and location within the garage. I have a 3.5 car garage ( L shape, wide single at front, with 2 cars wide at rear), with the 8' long pit towards the back of the front section. This works well if the back of the garage is clear, but can be restrictive during the winter when the convertable is stored in the rear section. Access is using a ladder cut to length at one end, although in retrospect I think I would go for a stepped end for easy access if you have the length.

Do not believe that a builder will be able to make it perfectly waterproof without proper tanking. A fibreglass lining will overcome this though. I fortunately installed a sump at one end with a fall along the length, which allows a submersible pump to be conveniently sited. And it needs it during the winter!

The most useful addition that I made is the inclusion of several ducts in the floor slab to allow electricity, water and pump outlets to be concealed. Lighting fittings should strictly meet the high specification flameproof requirements which can be very expensive! A petrol spill can be very dangerous!

Ventilation is not an issue that I considered, but should be probably be a requirement particularly if heavy vapours are likely to present (eg butane, propane LPG?).

Make sure that you build in the facilty to put boards over the pit that will be flush with the floor when in place. 4 ft scaffold boards (they double up with my scaffold tower) are ideal.

Ideas that I would include in any future redesign would be
1. longtidudinal rsj rails on both sides to allow a movable cross rsj or U section that can take a trolley jack. This would make working on suspension problems much easier.
2. make use of the natural fall of the ground for drainage/ventilation rather than pumped. This would be possible in my case as natural level of back garden is 2m below the garage floor.
3 a narrow pit is actually more useful than a wide one if you have the garage width to play with (see 1 above) as it allows jacking when vehicle is offset.

pmh (was peter)

Home Garage work pits - pmh
Not a problem if it is built on piles.

Should say.... Not a problem if house and garage are is built on piles.

pmh (was peter)

Home Garage work pits - mare
Depends on lots of things:

Do you need permission? - ask your architect / designer or if they don't know, call the planners. More than likely they will not want any extra work. If you described the extension in the original application as a garage / workshop then you should be ok. Their main concern would be the potential for a domestic garage to become a place of business.

Do get the builder to do the pit, doing it afterwards would be a nightmare. Obvious advice is get the change agreed before he starts, you will need soem redesign.

As regards the pit, you need to figure the length and depth: i don't know, but i suspect that they may be a depth over which some precautions may need to be installed if you're doing it properly. That may not apply to domestic garages though.

The actual construction of the pit could be blockwork with a concrete base or all concrete. it will depend on the local ground and water conditions. You may want to waterproof it or resign yourself to not using it when it rains. Also consider drainage of the pit and ramp the garage floor such that water runs away from it (doh!). Also consider how you cover it so it doesn't present a hazard when it's open and doesn't have a car over it.

Sorry for long post, HTH.
Home Garage work pits - mare
Ah, posted same time as pmh, read his post instead
Home Garage work pits - local yokel
Do check what the ground water levels are/have been in winter. I couldn't have one here as the water comes to within 24" of the surface every winter. Hope you are on chalk.
Home Garage work pits - trancer
Planning permission
Building regs
Correct Depth for one may not suit another
Fibreglass liners
Ventilation concens
Power points
Access when in use
Safety covers when not in use

Wouldn't it be easier, safer, more convienient, or maybe even cheaper to just get one of these instead?.


Far more useful I think as wheels would be unweighted allowing removal, height is adjustable so would be suitable for anyone or for jobs that you want at eye level or lower. When you move you can take it with you or sell it on, try doing that with a pit that potential house buyers may be put off by.
Home Garage work pits - local yokel
You do of course need a higher ceiling for a lift, and some people may be using roof space above a good-sized garage for a studio/office etc.
Home Garage work pits - Group B
Wouldn't it be easier, safer, more convienient, or maybe even cheaper
to just get one of these instead?.

Fine as long as you've got enough headroom in a domestic garage, which is often limited.

Home Garage work pits - Aprilia
I built my own pit some years ago. No planning permission required in my district at that time.
Cut out part of garage base slab with a concrete cutter.
Dug down about 6'6" and put a plastic liner in. Laid a 6" concerete base, then built up sides with blocks. Welded up a 4" angle iron frame for the top, with tines off to the sides so that it could be concreted in. Then use 4" boards to cover the pit. Couple of lengths of I-beam drop in place if I need to use a transmission jack etc. Took 3-days work start to finish.

Did this some years ago and its been dry as a bone, never seen a drop of water in it.

Think about how much you will realistically use it - no point in spending £1000's (if you employ a builder) to do the odd oil change.
There is a Spanish company (begins with 'F' I think - maybe Fagor??) make some lovely little single-post portable lifts you can wheel around - they are quite powerfull (I've worked under an S-class using one of these).
Home Garage work pits - Galaxy
A friend of mine bought a large house the other year with an equally large garage.

The garage has a very well built pit covered by wooden boards when not in use.

He discovered it when he went to view the property; the estate agent hadn't even noticed it!

I don't think the then current owner was into cars, either.
Home Garage work pits - Galaxy
Wouldn't it be easier, safer, more convienient, or maybe even cheaper
to just get one of these instead?.

If you do make sure that you get one that runs on 240 volts.

I'm not sure that they will let you have a 415 volt supply in a house.
Home Garage work pits - tr7v8
Lots of lifts are 3 phase 415V, which will cost a few bob to get installed just for a hoist! Some are available with single phase motors though as i know someone with one.
Very envious of you guys, wish I had a pit!
Home Garage work pits - madf
I have a pit in a garage 16metres wide x 7 metres deep. The pit is mounted in the central bay and is about 1.5metres deep. So under a car you have to stoop a little.. whch can be inconvenient but not painfully so. There is a recess cut into the side walls about 25cms square to enable boards to be places across. (old railways sleepers recessed to fit the floor recess). The boards are covered by a length of marine ply to flush the surface with th garage.

Removal and replacement of the above are a pain: railway sleepers are not light. And they have to be placed when up in the next garage recess.

Things to consider:
1. ground water (see prior posts ) ours is mounted at the top of a small incline
2. water drainage into pit from garage or wet cars.. (I have drilled drainage/aeration holes in the ply cover .. still gets damp in the winter)
3. Car wheel widths. If too wide a pit , a small car's wheelbase may not be wide enough to straddle the hole. SWMBO's Peugeot 106 only just scrapes along - 2 cm clearance either side. Very careful driving required.
4. Alignement with garage door. Surprisingly basic but ensure it is situated in middle of door opening. Whoever built ours managed to offset it by about 300cms.. makes entry and exit over the pit a little more challenging.
5. Access for electricity. I have a wall mounted power point within 3 metres. OK for extension reel. You may wish to consider built in facilities and lights. Professional installation of waterfprooed heavy duty facilities.

I don't have steps in or out just jump in/out but a small set of steps - removeable only - permanent would be in way.. are very useful

If like me, you use twice a year, lots of features are nice to have. If a frequent user, then essential.
Home Garage work pits - pmh
On the point of ventilation and fumes, the following makes for a salutary lesson! How many of us have changed a sender unit???


Read the final Apppendix for case histories.

pmh (was peter)

Home Garage work pits - Collos25
Under health and safty pits are no longer allowed in commercial premises how this effects a private individual I do not know.
Home Garage work pits - bell boy
Under health and safty pits are no longer allowed in commercial
premises how this effects a private individual I do not know.

ive just rung vosa and told them this and that all their commercial testing places need shutting today and they put the phone down................
For less than 2 grand you can buy a 240 volt mobile scissor hydraulic jack that allows wheel free access this might be worth a consideration but personally i would prefer the pit method but wouldnt use the glass fibre shell route i would rather go the apprilia way and dont forget if you get it dug out as the footings are being dug a kabota can do it in no time and you could use concrete reinforced walls all delivered by one big concrete mixer
Make sure you estimate your cubes correctly for the concrete last time i had 3 cubes delivered they only gave me 2 as the driver had skimmed me and it caused lots of problems as i couldnt get another cube till the next day and the first lot was well on the way to going solid
Home Garage work pits - mare
and you could use concrete reinforced walls all delivered by one big concrete mixer

pedant mode on:

Reinforced concrete is reinforced by steel. That is a different ball game from simply pouring a load of concrete into a hole or shutter.

Mass concrete may be fine for what you want though

pedant mode off
Home Garage work pits - corblimeyguvnar
Reinforced Concrete can be delivered in a big mixer (not value for money unless you are having a large load though), no need for steels, the mix contains fibres which dramatically increase the strength of the slab/block. Whether this would be suitable for a pit though I cannot say.
Drink Lager, Talk Piffle !
Home Garage work pits - Collos25
ive just rung vosa and told them this and that all
their commercial testing places need shutting today and they put the
phone down................

All new buildings are not allowed pits even the rail repair sheds have now purpose built work sheds with no pits they have been removed.Have you seen a main dealers with a pit these days.Certain existing premises have been given a dispensation for a short time to change but an employee has the disgression to refuse to work in it.But like all regs in the UK some will comply and some will not.
Home Garage work pits - L'escargot
Do check what the ground water levels are/have been in winter.
I couldn't have one here as the water comes to
within 24" of the surface every winter. Hope you are
on chalk.

It's not just ground water levels that can be a problem if you are on clay. We're on clay and what happens is that during the summer the soil cracks vertically to a depth greater than that of the pit. If we get a period of drought followed by a period of heavy rain (usually in early summer) the rain sinks through the cracks and gets into the pit. It's not a problem between autumn and spring (or during a wet summer) because frequent gentle rain causes the cracks to close up. It took me about 3 years to figure out why the pit got water in it some years but not others.
Home Garage work pits - mrmender
Thanks guys for all you advice. I will mull it all over a G&T on the flight back from Khartoum tonight.
Those ramp thingies are ok a friend has one but where do you store it when not being used (in a pit!!)
Drainage should not be a prob as i live on the side of a hill & next door is about 20Ft lower than us
Cheers MM
Home Garage work pits - pmh
Dont believe that being on a hill solves all your drainage problems! The ground at the back of my prperty is about 2.5m- 4m below the pit and I can still get more than 1m of water in the pit sometimes! This is in solid impermeable clay! We have done some investigation and have come to the conclusion that we are directly on the line between 2 ponds in the village, one of which feeds the other! The level in the pit seems to correlate with the level in the pond even though it is more than 100m away.

This is why I would try to install a direct 4" drain pipe out the pit bottom if you can, having a digger to hand makes all things possible.

pmh (was peter)

Home Garage work pits - Hugo {P}
A Cheap solution to those of you who have flooding pits may be to:

1) dig out the floor and replace with a concrete floor with .3mm DPM.

2) then, tank the sides by rendering then applying Thoroughseal to them. Ensure that the membrane coming out the floor is cut back and the thoroughseal is painted over this using a fillet approach.

A builder should be able to do this for you for a modest sum.

Home Garage work pits - wemyss
Actually Andy makes an interesting point. If I was still working (heaven forbid) I wouldnt dream of building anything which came under the edicts of 'working in confined spaces'
It really all began after the tragic deaths of three or four men working on the building of Carsington Reservoir which some of you may remember. One man went down a manhole and collapsed with toxic gases. The others followed to rescue him and all died. There is a memorial to them on site always arranged out with flowers to this day.
Legislation came into place and it was Draconian. At our Government Establishment we had always employed a man permanently working on unblocking drains etc.
I had to send him on 'Working in Confined Spaces Course' and also fitters who had to enter steam boilers.
But then came the fine detail of the law which includes that any person working below a depth of 1 metre on a manhole must have a gas detection machine. He must have safety harness with a winch to pull him out if necessary and a helper always with him.
But what about when the man is on leave etc?. Eventually I gave up and simply called in a Contractor.
Excuse my ramblings but I would not be surprised if Andy is correct in stating that pits are no longer allowed in commercial premises. If this extends into private residences I have no idea. The legislation for ourselves came under H&S at work but...I once remember a Contractor of ours who was prosecuted for falling off a ladder at home and injuring himself.. Sounds unbelievable but when he finally returned to work this is what he told us and he was a genuine type of guy.

Home Garage work pits - mrmender
Please don't start quoting HSE Regs i get enough at work
Before enteringa confined space the following MUST be done/ A tool box talk (TBT) with all concered. A risk assesment to make sure that the job has to be done by a person entering a confined space and there are no other options. Then you must obtain a gas free certificate, then All electrical sources must be isolated and certified. Then you can write A Hot work permit. With standby crew with BA set & fire extinguishers.
All i want to do is tinker with me motor!
Home Garage work pits - wemyss
Pretty good Mr Mender but don?t forget the fuses should be on my desk and also any equipment which is locked off means the keys must be deposited with your line Manager.
And of course COSH could also be involved so I hope you have all the technical sheets available.
And you just want to tinker with your motor.
Why not take up another hobby ?.
Home Garage work pits - Drash
My dad's homemade pit (concrete lined, recessed sleeper lid) is only about 5 feet deep but it has a seating arrangement which can be useful - it's just two batons fixed in the long walls about halfway up with a plank across. Loose enough to move with the backs of your legs, but wide enough it doesn't rotate and fall out, and it functions as a step down aswell. Not so great for getting a lot of leverage but easier on the back than stooping all the time. Don't know if that's a standard on shop bought ones but I find it useful addition.
Home Garage work pits - madf
I forgot to mention mine has a DPM with brick walls and a concrete floor: hence presumably no water.. The recess for sleepers is lined with removable plastic (ex sacks) to prevent the sleepers going damp and rotting . I still treat the sleepers every 3-4 years to hold back the rot.
Home Garage work pits - Sofa Spud
Re: health and safety considerations with pits. If an employee has the right to refuse to work in a pit surely they should have a similar right to refuse to work under a ramp! In my limited experience of working in pits or under lifted vehicles I think I worried less when in a pit!!!
Home Garage work pits - No FM2R
Its related to gas and fume collection not big wieghts dropping on your head.
Home Garage work pits - mikk
Mechs were taking a fuel tank off and the pit filled with vapour without them realizing.
There was a flash back to a heater and men lost their lives in the pit. This was a public service vehicle and it never got into the press.
All it needs though is a slight fuel leak, still air in the pit and the heavier than air fuel vapour sinks to the bottom of the pit.
Then either a spark or vapour spilling out of the pit to an ignition point.

Home Garage work pits - L'escargot
I checked my pit yesterday and the combination of a dry period followed by the recent heavy rain had resulted in about 1/2" water at the bottom. It wasn't deep enough to warrant getting out my submersible pump so I just ladled it out into a plastic storage bin using a plastic dustpan. I have an oscillating desk fan on a shelf in the pit to circulate the air to complete the drying process.

Regarding the pump, can you get pumps that don't need priming and which will reduce the level down to almost zero? Mine needs to be in quite a few inches for it to become primed (I usually have to prime it in a bowl of water first and then quickly transfer it into the water in the pit) and it then stops pumping at about 1/4".
Home Garage work pits - pmh
My current pump with an internal level switch (not the old style floating float switch on a cable)made by Stuart Turner is by far the best I have used. All previous pumps (3 over 10 yrs) have needed priming. I used to prime them by forcing mains pressure water down the outlet side of the pump. Worked every time. The only way to get zero depth clearance is to put a sump in the bottom of the pit.

pmh (was peter)

Home Garage work pits - Collos25
Just been chatting to a building regs man at a UK council I do work for and as I said before pits are a no no as it would be in contravention of the building and health and safety regs and it would also be a criminal offence for the builder to build one for you as he would be building something that could endanger life. But who cares about rules and regulation Two Jags being the being the Icon we should all follow.
Home Garage work pits - mrmender
No wonder Fred Dibnah had to close his pretend coal mine!
Home Garage work pits - Mondaywoe
Bear in mind that Reliant Robin owners have health and safety issues with pits...........

Home Garage work pits - mrmender
Robin owners need to go on a hse course before getting in!

Ask Honest John

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