gas pipe in under floor or above ceiling?

[jack101]

Hi, i need some advice on where i should run the gas pipe inside a flat.

it will be lpg gas coming underground into the property via a yellow plastic pipe and terminating in the boiler cupboard which is at the far end of the flat and the kitchen is at the other end of the flat. i need to know how the gas pipe should be run so i can make plans for the other work. the flat has existing concrete floor with a track cut into it for foul drainage. the whole floor will have insulation laid on it and have screed poured over the top of underfloor heating pipes.

it is physically possible to run the gas pipe under the floor but im not sure if this is allowed and what kind of sleeve or duct is needed.

the alternative is to run the gas pipe above the ceiling which is gyproc on 4/5 inch timber on concrete (this is the floor of the flat above) the problem with this option is that there are steel beams supporting the concrete ceiling and i would have to drill through these to run the pipe. i dont know what the rules are about venting or ducting or joints in this pipe.

both options will need part of the pipes run in stud partitions at some point as well

on a side note the cold and hot water will have to run this way as well so whats best under floor or above ceilings? please answer for gas and water.

thanks

 

[unguided1]

put it in the screed and make sure you use plastic coated copper for the gas and then for the hot and cold pipes I always coat them in denso tape others on here will have different ways but thats how I would do it

 

[SafeGasInstall]

i have used before overflow pipe to protect hot and cold from concrete

 

[Bartdude]

I've used this kind of thing before,not with UFH underneath though but it might be helpful.

Pipe and Cabling Ducting - Manthorpe Building Products

 

[jack101]

put it in the screed and make sure you use plastic coated copper for the gas and then for the hot and cold pipes I always coat them in denso tape others on here will have different ways but thats how I would do it

thanks for the advice i should add:

it is not concrete screed, it is the self levelling type as seen on grand designs. i have no problem with protecting the pipe against corrosion, just thought i should give you all the facts.
what about cold water running through the screed, wont it heat up when heating is on?can i assume there should be no joins?

 

[jack101]

sorry i forgot to ask: is it possible to use iron or yellow plastic for the gas pipe? its lpg.

the hot and cold will be plastic pipe, still need protection or ducting?

 

[PlumbBobBob]

ducting is preferred in case of replacement in the future.plastic would be easier to replace because of it's flexability and lengths available so no joints in the ducting.

 

[jack101]

ducting is preferred in case of replacement in the future.plastic would be easier to replace because of it's flexability and lengths available so no joints in the ducting.

was that plastic for hot and cold or for gas?

 

[jack101]

im getting conflicting advice from gas safe registered folk. some say you cant run through the screed and some say you can. who to trust? why is there conflicting advice? noth cannot be correct.

 

[PlumbBobBob]

hot and cold. afraid i'm not gas safe so i don't want to comment on the gas side really. other chaps on here will be better able to guide you on gas side.

 

[Reg Man]

Jack: You cannot run MDPE plastic pipe buried in the ground through under the wall/foundations into the property. Correct Method is to bring it above ground external using a fibre glass ducted sleeve and transition fitting to convert it to steel or copper. Not a good idea to run PE inside the property.

 

[jack101]

yes i remember now that the lpg supplier told me that, i just forgot about it. the lpg gas enters the flat above ground. ive had it confirmed by gas safe register technical that it is ok to run coated gas pipe in the floor screed with 25mm min cover.
anyone have advice on the cold water pipe getting warm when the heating is on?

 

[AWheating]

you will need to insulate between the hot and cold pipework and the underfloor heating.

 

[nysk2008]

Dont forget there are differennt maximum pressure allowable pressure drops on LPG vs NG. Had a look in my book and it says about pipework in solid floors

Copper: Must be fully annealed and factory sheathed and is usually laid into the floor screed. Where it is laid in a concreate slab it should be placed inside a plasic sheath with no joins within the sheath.

Mild Steel: Must be fully protected with petroleum impregnated bandage or suitable bituminious paint

Stainless steel: Only factory sheathed corrugated can be laid.

if laid in concreate in addition to the method with copper it is possible to lay the pipe in a pre formed duct, with a protective cover over the pipe, alternatively another additional soft covering that will allow some movement may be used.

Dont forget, no compressions and joints should be to a minimum

Hope this helps

 

[aggis]

Sorry but I think you'd be best getting a Gas Safe Register Engineer to do the job.

 

[PlumbingSucks]

run the pipes on the existing concrete floor then lay the insulation for ufh ontop of that with it channeled out where the pipes run then your ufh on that then screed ontop. Pipes will be well insulated from ufh and not in contact with the screed. Still use coated copper for gas as laying on excisting concrete and mayebe 9mm lagging for hot and cold.

 

[Gray0689]

run the pipes on the existing concrete floor then lay the insulation for ufh ontop of that with it channeled out where the pipes run then your ufh on that then screed ontop. Pipes will be well insulated from ufh and not in contact with the screed. Still use coated copper for gas as laying on excisting concrete and mayebe 9mm lagging for hot and cold.

As above it's spot on
But do use lagging on hot and cold

 

[Dotty]

As has been said also, get a GSR guy in. Ask him about Tracpipe. Bit more pricey but what's that against peace of mind?