Hot and cold water pipe insulation

[orbit123]

Hi,
we're getting house fully re-plumbed at the moment and have open access to all the pipework. I'm keen to put insulation (just the foam stuff) over all the hot and cold pipe runs to insulate them. Its quite a big house and there are some big runs where hot and cold pipes are next to each other. The plumber doesn't seem sure its worth doing in the heated areas of the house, however, its hard to judge if thats because its not worth it or because he doesn't feel like doing it.

My thoughts are that we're better to stop heat loss/gain where we can and it would also stop the case where cold water ends up warm for for the first few seconds its switched on (we'll have hot water circulation).

Any thoughts or experience?

Would it be worth doing same with radiator pipes where they're between ground and first floors (we will do any below ground floor). I can see with these pipes that the heat lost from the pipe is still heating the house - however, it needs to heat the cavity, floor and carpet before it gets to the room?

Its not a huge job to do it as its all open but won't bother if it seems like waste.

thanks.

[Smiler.]

He's just being lazy.

The cold won't need doing unless there is a risk of zero or near zero temperatures.

The hot water & the heating flow & return should be insulated.