About to replace old lead/copper water pipe with MDPE pipe - Questions

[diyenthusiat]

Hello everyone.

 

Thanks for a great forum.  This is my very first post, so apologies for any mistakes.  We have been living in a large semi-detached house (1930s) for over 5 years. About 18 months ago, I called out Yorkshire Water because our water flow/pressure was low. They did a number of tests and concluded that the flow from our kitchen sink tap is around 8-10 ltrs per minute, but the outside boundary test showed that Yorkshire Water's actual flow rate is 35-40 ltrs per minute.  They said the reason for the low flow rate on our side is because we most likely either have old lead or copper pipes feeding into the property.  They advised that although they are responsible on the street side, any change pipework within our boundary is our responsibility.  So fast forward to present time, we're thinking that due to the pressure being so low it might be worth changing to an MDPE pipe.

 

The MDPE pipe size I'm thinking of is 32mm, rather than 25mm but a builder said it won't make any difference because the incoming connection from Yorkshire Water is either only 25mm or it will have a small lead pipe connection to which the MDPE pipe would need to be attached to.  But I've read in a few places that having a larger diameter pipe makes a big difference.  Could someone please advise if this matters?  Also another point worth noting is that the distance between the water connection on street and our stop tap is 25 mtrs, so not sure if having a bigger pipe has any impact on the amount of flow we would be able to get.

 

Finally, based on what I find out on here, if I did decide to go 32mm, what connectors would I need to correctly connect it to either a 25mm or lead pipe?

 

Thanks in advance