can plastic pipes touch?

[Jennie]

Hiya,
I'm running two plastic hot/cold 15mm pipes into an extension to feed a shower/basin/toilet/utility sink.
One of the runs involves an elbow and passover so the hot can run horizontally above the cold.
How much effort should I go to with this passover? I'm using plastic pipe with brass compression fittings (and inserts). Is it OK if the pipes momentarily touch, or should I perhaps do the passover in copper and keep the two pipes separate?
Thanks for your advice?
Jennie

 

[kozak1968]

You should try to keep the pipes apart otherwise heat will transfer to the cold, no one likes brushing their teeth in warm water. You should lag hot and cold to reduce the tranfer of heat.

 

[Paulus]

:iagree: wholeheartedly.

 

[PlumbBobBob]

:iagree: x2

 

[Jennie]

What's best to lag with? Would it be the tubes of horsehair lagging?

 

[mcniven]

Any plumbing merchant or b&q will have the correct pipe insulation its like a length of foam cheap and easy

 

[AWheating]

ideally 13mm lagging in a heated zone, but unless its new build you can get away with less, but the thicker the better.