Best way to plumb hot and cold water in a house - Qualpex or alupex, lagged or not?

JamesGCo

I am currently having my 1970's bungalow renovated.

I assumed that the hot and cold water piping would be done with pre-insulated alu-pex type but they have used qualpex with is fed through a black protective pipe (not lagged) and there is no lagging on either hot or cold. I would assume that the pipes being laid on the subfloor should be insulated, perhaps not necessarily the cold water but definitely the hot pipes. The contractor tells me that most plumbing is done this way! but that sounds wrong to me.

I spoke to one plumber I know and he says that as far as he would be concerned the standard nowadays is to use pre-insulated Alu-pex for both hot and cold throughout the entire house, including upstairs, that's the way the company he works for have been doing it for years.

what are other peoples opinions on this?

Tom44

Simply

Which would you genuinely think is better, insulated or non insulated ?

The answer is now the industry norm.

I've no problem with qualplex if done right, with copper where solid runs are required (hot press) been an example.

Alupex is a semi rigid pipe and looks well.

dathi

taken from the building regulations part L TGDs

2.2.4.1 All hot water storage vessels, pipes and ducts associated with the provision of heating and hot water in a dwelling should be insulated to prevent heat loss. Hot water pipes and ducts within the normally heated area of the dwelling that contribute to the heat requirement of the dwelling do not require insulation (except those referred to in paragraph 2.2.4.4). Pipes and ducts which are incorporated into wall, floor or roof construction should be insulated

JamesGCo

Thanks,

I couldn't get my head around why you wouldn't naturally lag everything, it's not exactly expensive and you only have one chance to do it.

Thanks for the Reg quote.