Hello, This is My first post on here so please go easy. lol Im in need of some help and advice and i thought this would be a good place to start as im in ScrewFix every other day at the moment. My self and my wife bought our first home a few months back now and are currently in the process of completely renovating it. Its a semi detached Ex Council bungalow in Cornwall, we literally spent all the money we had in the world to get the mortgage, so before anybody tells me to just get a plumber in, the simple reality is we don't have the money to pay anybody for the work. The whole house needs re plumbing, we literally don't have any running water whatsoever at present and im just about to start the first fix stage routeing the copper pipe to where my sinks bath and boiler will go. The bungalow will eventually have a total of 7 rads, 1 bath 2 sinks,( kitchen and bathroom( and we will have a new combi boiler installed (professionally) My first question is that the old mains inlet was only 15mm copper coming off a 25mm MDPE Pipe with stop cock. Should i upgrade this to a 22mm pipe? Will this benefit? and do all boilers need a 22mm copper inlet and outlet? or can i go from 15mm up to 22mm for the boiler. i might add that the water pressure is seriously low where we live so i will be installing a salamder homeboost system. By doing this will this eradicate the need for a 22mm mains pipe from the MDPE outside? ive drawn a quick sketch of the plan, if anybody can cast an eye over it to see if this is viable that would be great.