Pipes under the Celotex - but how to fix?

[Steve2381]

Hi all
Working on my extension... concrete slab is down, and the builder has put DPC polythene over the floor, then his 100mm of Celotex insulation.
On top of that goes the screed.

I have a hot and cold feed to the kitchen sink and ground floor WC to put it.

He wants it run under the Celotex cut in a groove, because their is underfloor heating pipes going all over the top of the Celotex.

Problem is.. how can I fix the pipes? I can't drill the concrete slab for clips as that will make a hole in the DPC.
Using 22mm copper with felt insulation should make the pipes quite sturdy when they are laid, but the run is 6M and I don't want rattling pipes.

The gas man is coming out to lay a copper gas across to the fire later this week, and I believe the plan is to do the same for that.

All I can think is to make sure the grooves are cut in the insulation as a neat tight fit, with the felt pipe insulation helping to hold them still.

Once the screed is in place, the ends of the pipes will be solid anyway.

Any input welcome!

Thanks, Steve

Untitled

• Steve2381
• 7 Jan 2013
• 1

 

[CBF]

hot & cold pipework should be accessible or removable you need to use something like

http://www.polypipe.com/plasticplum...olyplumb-manifold-system/barrier-pipe-in-pipe

 

[Steve2381]

Mmm... can't run copper gas through that however.
Plus... hate plastic pipe. Just a personal thing.

I can't run a duct. As it will interfere with the under floor heating runs. Plus I don't want a duct lid running across my tiled floor.

Its never simple is it

 

[JohnD]

it is especially important to avoid joints in pipes that you can't get at.

 

[CBF]

taken from the water regs

7.—(1) No water fitting shall be embedded in any wall or solid floor.
(2) No fitting which is designed to be operated or maintained, whether manually or electronically, or which consists of a joint, shall be a concealed water fitting.

 

[Steve2381]

OK. So there is no way possible to run copper piping in the floor at all?
I know that you can't bury joints in the screed etc, but I can't put a duct in the screed - as that will still be under the tiled floor (and therefore still unaccessable) and also mess up the under floor heating.

Therefore its impossible then surely for the gas guy later this week to install a gas pipe to the fire?
He told me he was going to run it in copper under the Celotex.

I suppose we could install a duct in the screed for the gas as well... but that then trashes the planned underfloor heating layout.

I think I will let the builder stick the pipes in how he likes instead (he offered to do them) then and they can take the blame if its wrong.
I thought I was making a better job if it, but apparently not!

Thanks

 

[JohnD]

Why not run the pipes round the edge of the room, either in a floor duct avoiding the UFH, or behind a battened skirting, with no plaster behind?

 

[Steve2381]

Can't do the skirting thing - too many external doors in the way.

There is no route that doesn't cut across the underfloor heating. That is why I think the builder suggested the pipe went under the Celotex (which is obviously wrong)
Plus one side of the room is curved, so a duct around that will be a nightmare to install.

Oh well. Not sure what I am doing now!

 

[CBF]

the water regs apply to potable water ie hot & cold not heating which is why you can screed over the heating pipes, you can use what i suggested for the pipes which gives you no joints under the floor & it can be removed, you say you don't like plastic pipes what do you think the pipes for your underfloor heating are made of ? if you let your builder do what he wants then what happens if you have a good building inspector & he won't pass the pipework ? or you have a leak in 5 yrs time who is going to smash up your loverly tiles & screed floor to repair it ? do the job right & do it once.
hair felt lagging is not enough of a protector either concrete & screed will eat straight through that,
you can run gas the way you want providing it's tracpipe or plastic coated copper & the joints must be soldered (not compression) & protected not with hair felt & the pipe must be fully tested for leaks before the screed goes down but your RGI should know this.

http://www.ukcopperboard.co.uk/lite...on-Tips/Domestic-gas-installation-testing.pdf

 

[CBF]

it's sometimes funny what is classed as accessible with regard to water pipes for example pipes inside a stud wall are accessible, a duct in the floor with a removable lid then tiled over are accessible, cut two channels in a plastered wall for a shower if you plaster over them before tiling they aren't accessible but just tile over them then they are accessible

 

[Steve2381]

Tracpipe is madly expensive, and seeing as my lottery numbers haven't yet come up, I won't be using that.

Protected copper pipes in the screed have worked fine for the last God knows how many years... its how my extension was done 15 years ago.

But.... regs are regs so I will have to play along nicely.

As for felt lagging not being enough... They were going in/under the Celotex, not in the concrete/screed.

Thanks for the advice

 

[doitall]

Plastic coated copper for gas, it has to take the shortest road from one side to the other, but wasn't there a reg about not being in the same floor with underfloor heating.

Plastic pipe in conduit satisfies the water regs (you can buy pipe in pipe) again I would run it around the edge.

Clearly a duct in the screed will cover the regs for all the services.

As for letting the builder chuck them in, crazy idea.

 

[CBF]

Protected copper pipes in the screed have worked fine for the last God knows how many years... its how my extension was done 15 years ago.

As for felt lagging not being enough... They were going in/under the Celotex, not in the concrete/screed.

people said the same about smoking, things change.

yes i know they were but you were still laying them on the concrete base & hair felt isn't a protective sleeve

 

[Dan Robinson]

Go one - say it a few more times... it might sink in .

 

[CBF]

Go one - say it a few more times... it might sink in .

i very much doubt it