central heating pipes in stud wall

Try not to nail through them, that's all.

And a sleeving that will allow them to move in their notches without creaking and banging, is good, too.

Insulation a good idea, but not mandatory.

No problem. I did just this when installing my heating some 30 years ago, as I hate seeing pipes, or just boxing them in. I'd insulate them with the old felt sleeving if you can still find it - mainly to prevent creaking if it touches anything.

Use plastic barrier pipe (Hep2O etc.) inside the wall - converting to copper outside the wall if you wish. Avoid having joints inside the wall.

Why? Copper is known to have a long long life. Plastic not.

It's pretty inevitable there will be some. And using plastic in a mainly copper system makes for more joints.

But to put things in perspective, hacking into a plasterboard wall to fix a leak could actually be cheaper to make good than lifting a posh wood floor.

Plastic pipe has a 50 year warranty.

but does that notional "receipt required" 50years gtee include the fittings? (bends, Ts etc) and is it a "refund only the cost of purchase" type arsewipe gtee?

I like plastic pipe but hate marketing types... ;>)

Jim K

Would that be the same as the current crop of 'lifetime' warranties offered on cars?

There's evidence all around you that copper lasts well. And also plenty that plastic doesn't.

I hope not. Plastic pipe does not have an odeometer.

I use both. My CH was done in plastic as most of the ceilings were down when I installed it but I used copper when I installed the next door but one neighbour's CH .

I am happy with both installations.

The key advantage is that plastic can be cabled in - quick, easy, and reduces joints. Straight pipe in up to 6m lengths, coil in longer lengths but can be a pain.

OTOH - if I was doing the job again - I would take on the extra effort and expense of copper - just for the bomb-proof security against leaks inside the walls.

I can assure you it most certainly is!!

Took me less than an hour INCLUDING going to the BM to get a slip coupling.

whats the warranty on the O-rings?

Depends if your name is Drivel or not.

I have seen failed copper pipe, I have not seen failed plastic pipe (yet).

You don't need to use O-ring fittings on plastic pipe, my CH is plumbed in plastic with brass compression fittings, very cheap, vewy wewiabwel.

Manifold section by the boiler is copper though.

I would be inclined to put foil tape on the back of the PB in the partition though to make me feel better if the next owner didn't use a pipe finder. I'd also use electrical cable type routing rules for the pipe too, ie vert or horiz only from visible pipe entries so there's a chance of missing them for a half careful subsequent owner/tradesman.

I've had (some) plastic pipe in my house for over 20 years. I recently had to re-jig some of it - and the pipe *and* fittings were as good as new.

Absolutely not! By using plastic, you can have a single length from above the ceiling, down to where it emerges for the towel rad with no joints whatsoever *inside* the wall. That's far more difficult to achieve with copper because of its inflexibility. I would use copper push-fit to join up with the copper pipe, and the plastic would be barely visible.

True - but I'm not quite sure of the relevance!

You're going to make a neat, tight, right angle bend in the plastic to bring it out through the wall and into the fitting, without a joint?

No push fit joint is invisible. Only end feed copper fittings get close to this. But I'd have any as needed inside the wall, rather than on show anyway. With just a neatly made bend out of the wall to the fitting.

I'm afraid it depends on priorities. My idea for running pipes inside a wall is to get the neatest possible job. So no nasty push fit thingies outside the wall. I'd enough confidence in my soldering not to be concerned about leaks.

You shouldn't need a right-angle bend. You can bring the pipe out through the plasterboard at a shallow angle - particularly if it's behind a radiator.

If you need it to emerge at right angles to the wall, you've got the internal cavity (75mm or whatever) in which to form a radius.

I didn't say that the push-fit fitting would be invisible, but that the plastic pipe would be 'barely' visible - because only a small length needs to come out of the wall before going into the copper push-fit fitting. These fittings - in case you're not familiar with them - are nothing like the large plastic fittings, and are only a little larger than solder fittings and almost certainly smaller than compression fittings. Here's an example: