Building footings over main gas and electric pipes

[holmslaw]

@ holmslaw, another exaggerated post from you, in such circumstances my official advice is always to have the mains relocated as am professionally bound to do so, I write to the homeowner specifically recommending that such a mains pipe is relocated and if they choose to do otherwise that is their responsibility,

So in your letter do you tell them that a contained gas leak could cause an explosion that would blow the house down and kill anyone in the vicinty. Or do you say it would be inconvenient and if it did leak we would move the main. I don't think courts look kindly on people who play russian roulette with other peoples lives.

What do your insurers think of your 'get out' clause?

the reality is though that there are probably millions of gas mains that have been built over and they operate quite happily and safely,

Until they explode, thats why there's a bit of rush on to replace old gas mains.

I suspect that there are many more accidents or leaks caused by dodgy gas fitters connecting up boilers or fires incorrectly or by people working on gas who shouldn’t or whatever.

Thats got nothing to do with building over gas pipes.

No one is denying there is a risk (as there is with practically everything in life).

You obviously don't understand or care about risk assessment, its about balancing cause and effect. And you causing an explosion with the effect that peolpe die doesn't balance.

Official advice is to relocate, reality is more often than not somewhat different though.

You mean for callous irresponsible people such as yourself.

I sleep extremely well at night thank you for asking.

I suppose you do with your could'nt care less attitude.

 

[freddiemercurystwin]

Oh dear you’re really getting in a bit of a tizz about this aren’t you? I’m quite happy with the stance I take, your continual bleating on won’t change the way I approach this. Feel free to continue getting blue in the face old chap.

 

[theoldun]

Many people refer to underground gas pipes as gas mains, and we all know that by this they mean an underground gas pipe, how ever the pipe in question is not a gas main with a possible pressure of 7 bar, but a gas service at a pressure of between 30 to 70 mb.
We would agree that it is illegal to build over a gas main, how ever it would be very unlikely that anyone would build over the top of a gas main as gas mains are either in the verge, public footpath or public highway. A gas main under a private road will have an easement attached to the owners deeds of said road.
A gas main and gas service are two different animals and we fully understood that even though FM called the gas pipe by it’s common name we knew that he was referring to a gas service..
We note that the post by holmslaw states
Quote; (The line of the service pipe must be on a line at right angles to the main and direct to the meter position. The line must take the shortest possible route but may require diversion to negotiate obstructions. The service pipe must not be laid under any buildings including garages). End of quote.
However holmslaw does not finish the regulation by including: (If this is not possible, then a dimensioned drawing must be produced to record the actual route).
Just couple other points. The OP does not know whether there is a foundation or footing under the present garage door as he has dug no trial holes Possibly there may already be a found there. When pulling founds we often pull across the front of a a garage especially if it is integral.
The builder, developer would have installed the ducting under garage and the gas transporter would have laid the service. We feel sure that no gas transporter would have laid a service with a possibility of a contained gas leak that could cause an explosion.
oldun

 

[DarrenSL]

Thanks to everyone who has contributed to this thread.

Taking all the facts together I think the best option for me will to simply move the meters to a more convenient place within the garage i.e. closer to the front. I'm pretty sure there are no foundations so I'll probably go with a pvc cladding option and avoid the issue of laying foundations over the gas pipe.

The gas pipe will be beneath the garage but that's where it is already so hopefully NatGrid won't have an issue with moving the meter. (I could argue that if they consider it so dangerous, they should be moving the meter outside for free )

Thanks again.

 

[LM1980]

I know this thread is two years old but I want to clear up a lot of miss information and inform those who read this in the future the correct facts.

Firstly a gas pipe, gas service pipe and a gas main are three different things.

1) A gas pipe is what is installed after the gas meter inside your house/building.
2) A service pipe is what supplies gas to your meter from the street.
3) A gas main is the pipe that runs down your road supplying the service pipes.

In brief the gas main and service pipes can have anything between 24mb to 75mb of gas pressure in a low pressure main and in a medium pressure main it will be anything over 75mb.

For gas pipe installed in a house/dwelling the following regulation/document is applied
BS6891:2005 + A2:2008. This document covers copper, steel and polyethylene (PE) which is yellow.

All three types of gas pipe can be buried although copper and steel need protection from corrosion.
PE pipe is plastic and requires no protection under normal installation. Old steel gas service pipes tend to have PE pipe slid up the middle to save digging up the old service pipe. This steel sleeve adds protection but is not a genuine sleeve for the PE service pipe and there would require adequate sleeving if required/demanded.

The regulations are not completely clear cut on buried gas pipes/service pipes under buildings, however.

If you know your service pipe comes down your drive to a meter box on the side of your house and you decide to build an extension over it the following applies.

Don't listen to your builder.
Don't listen to the building control officer.
These two people don't know the correct regulations or where to find the correct information.

Your builder if digging near a gas service pipe cannot use a mechanical digger within 0.5meters of it and must hand dig around it. If the builder exposes the gas service pipe, PE or steel they must inform the responsible person of the house/property and stop work immediately.

Builders, building control officers will just tell you that it is ok to build over it. WRONG WRONG WRONG.

As the responsible person (the home owner) you must do 1 of 2 things, or both. Call a Gas Safe registered gas engineer. Go to www.gassaferegister.co.uk and find a local registered gas engineer.
They will advise (if they know, which they should like I do) to call national grid or who ever looks after the gas mains/service pipes (0800111999). These people are the gas transporter and are responsible for all gas pipe work infrastructure up to the isolation valve before the meter. The gas meter belongs to the supplier. Your installation belongs to you.

In my area it is National Grids responsibility to look after the service pipes and gas mains. They are very helpful. You, the home owner/responsible person or the gas safe registered engineer will tell them that your builder as uncovered the service pipe to your house. They will demand you stop the builder from working and that your turn of the gas at the meter and all appliances etc.

They will send out someone to survey what has been uncovered and may uncover more to expose more pipe.

Firstly they will say your meter must be moved. Although, depending on the depth the pipe is buried may affect his decision. However, most service pipes are not at the correct depth of below 375mm from the surface as I know all to well.

If deeper, like deeper than 1 meter or more you can build small foundations either side of the pipe before putting foundations over it. However this will not be the case trust me.

I have seen builders lay a foundation under the service pipe and build a lintel over the top. This is not adequate. The service pipe would need to be sleeved first by Nation Grid. They will not do this however for a number of reasons.

1) If the service pipe is PE and has fittings, like elbows, couplers etc then you cant build over it as you can't builder over pipes with joints. BS6891:2005 (yes this is normally used after the gas meter) states regulation 8.15.1 table 4 that PE pipe with fittings can not be build over or be installed under a building.
2) The service pipe is not your property and you cannot not conceal it from inspection. Your drive can be dug up, you house cannot without damaging the foundations.
3) Tha Gas Act 1995/2000 comes into play and this is one big document riddled with dos and don'ts.

You also have IGE/TD/4 which covers gas service pipe and gas mains etc. I have not read this document as it cost £165 and I have purchased loads of these documents in the past at a cost of thousands of pounds.

If your builder decides to build over the gas pipe in anyway and even if the building control officer signs off on it this situation will bite you in the arse.

The pipe will either get squashed or the joint that 9 times out of 10 that puts the service pipe at a right angle to the meter box may crack and leak gas. The gas will build up and up and up until the ground is saturated with gas and only has one more place to go, YOUR HOUSE. You wake up one morning, if you are alive and you turn a light on, or the kettle. You will more than likely be killed within 1000th of a second from the almighty gas explosion. You and your family will be killed.

The ground will hold a massive amount of gas before seeping upwards.

The gas transporter, supplier and an half decent builder, gas safe registered engineer will tell you not to build over any form of gas pipe. If you do and, because you can in some situations and it isn't done correctly then you may be screwed.

99% of the time no gas service pipe or mains gas pipe will ever be built on. You can put a gas pipe downstream (after the gas meter) of the gas meter under a structure but only as long as you protect it correctly by following the regulations in place for the type of installation you have.

Gas suppliers and companies like National Grid are fighting to have a clear cut regulation added to the Gas Safety (installation & Use) Regulations 1998 to prohibit any gas pipe being build over.

Just don't do it. Simples.

 

[noseall]

The last post was really interesting.

 

[Klondike]

I can fully understand the reasoning behind keeping gas pipes protected/away from house extensions. But....our extension was built some thirty years ago. Now we are being told that we have to pay to now have the supply diverted and our drive way dug up. Can the gas board do this retrospectively.
The regs all seem to be very confusing depending on which one you read.
Can we sue the council for allowing this to be done all those years ago?
Did this regs apply in 1987.
Thanks.