General advice on chasing in pipework needed.

[Sharpey]

Hello all.

I have a few general plumbing questions I was hoping you guys could help with.

I have to get some radiator and water pipes fitted soon to go in to a cloakroom. I wanted to have the pipes installed under the ground so they're hidden. My dad is doing the plumbing and it's possible he might use plastic pipes for both heating and water.

What I want to know is...

1) When the pipes are laid underground, do they need to be insulated in any way? The holes are going to be filled with concrete. If so, what is used to wrap around them?
Are there any issues regarding having water/heating pipes next to each other?
I read somewhere that water pipes are not allowed to be chased in to a wall, is this true and does the same apply to floors as well?

2) Are plastic pipes any thicker than copper ones? I wanted to fit a couple of small chrome radsnaps on the two heating pipes protruding from the floor and was wondering whether they could fit on to plastic pipes as well as copper (sorry is this seems like a daft question).

That's it really. Any help would be appreciated.

 

[PhillCO2]

You can get plastic covered copper piping which I believe is suitable for concreting over. You can also use the PVC piping.
The tails out of the radiator should be copper which you can then connect onto plastic with pushfit or compression connectors.

Personally if it is possible I would cut out a channel and put in a 2 inch galvanised steel trunking just below surface level and run the pipework in that. You can concrete or tile over the top once the lid is on but it then makes it much easier to inspect or replace at a later date in the event of leaks etc.

I'm not a plumber by trade though so the pros may advise otherwise.

 

[Sharpey]

That steel trunking sounds like a plan Phil, thanks for the reply.

I have actually decided to have the water pipes outside now against the wall as I have found out you can get chrome plated pipe so it should be possible to make a neat feature out of those.

As for the heating pipes, I still intend to have them inside the ground. I have a coil of plastic pipe, and you mention that this can be connected to the towel rail radiator via pushfit/compression connectors. The thing is, I want all the fittings/pipes etc to be quite discreet and the same colour (chrome) so do you know if such things are available?

Also, a lot of people say you shouldn't have a bend if you are planning to concrete in pipes. I am probably misunderstanding what is meant by this, as you need the pipe to bend upwards to come out of the ground no? If I decide to use copper pipes for the heating could I not just have a soldered joint for the pipe coming out of the ground, would that suffice? Could I cover it in Denso tape and concrete over that if I decide not to go the trunking route?

Sorry for all the daft questions!

 

[PhillCO2]

I would say your best option for the radiator in that case would be to get some chromed 15mm copper. Use this for the tails out of the radiator down to the floor. You can then connect this onto the PVC pipe with a pushfit or compression fitting, bear in mind the pushfits tend to have a larger profile but the compression fits need room to get a spanner in to tighten them.

You can get the compression fittings in brass or chromed variants, I don't see any issue with bending the pipe up to 90 degrees using a proper pipe bender/bending springs.

Personally in this situation I would probably come down from the radiator into the trunking in chromed copper with a 90 degree bend on to bring it in line with the PVC pipe sat in the trunk and then get a straight coupler on. Push or compression by your choice. I would be tempted to put a straight compression fit with a valve on there then it can be easily isolate if you need to remove the radiator/radiator valves in the future.
You can get some nice looking chromed wall clips for the pipework from most shops too if you are making a feature of it.

The pipe out of the radiator should always be copper though even if it is just a short 'tail'

 

[seco services]

The pipe out of the radiator should always be copper though even if it is just a short 'tail'

Why's that ?

 

[PhillCO2]

The pipe out of the radiator should always be copper though even if it is just a short 'tail'

Why's that ?

It's not a rule it's just prefered by most plumbers I have ever dealt with. Some have said the copper pipe is more robust against accidental damage, others just because it looks better especially with radsnaps due it not being as flexible.

 

[seco services]

It's not a rule

ok

 

[dcawkwell]

Put the plastic pipes in conduit.

What's wrong with a nice wooden floor?

Hat concrete floors cold and a hell of a mess if they need to be taken
up for any reason.

 

[Sharpey]

Right, thanks again for the replies. A lot to mull over.

The floor is actually concrete so I've no choice in that matter.

I will think this over and update when I have made my mind up but it's beginning to make more sense to me now.

 

[Sharpey]

Hi again. OK, I've read up on this a little more and it would appear there is no real consensus on what the best method is for burying copper pipes in concrete.

I am thinking a wooden box within the concrete channel with a plyboard lid in line with the surrounding floor (again, I've read confliicting reports on using steel near copper so opted for this method). Does this sound OK?

I will then have plastic pipes running within, have two copper tails connected vie elbows. Maybe use a couple of pipe clips within the box to suspend the pipes and give them support.

Does this sound like a plan? Is there anything I need to be made aware of?

If so, does any one have any tips on the best type of wood to use for the box, as I will be using concrete to make good on the sides and beneath. Also, any general tips on how to get the box right and level would be appreciated.

Thanks.