Sorry one last related question on this. We've been given option to either just replace the boiler and gas supply pipe to it or do a full replumb of the central heating and new rads. We're on 8mm mircobore now. I don't have any experience of either and wondering to what extent the house can be put back afterwards without damage to flooring/walls etc. Basically we can't afford to fully refurbish property but would like to get the fundamentals right i.e. electrics and central heating/hot water but not if that means living with holes in walls, floors not put back or damaged. I imagine this is an issue for a lot of customers? We could save and try to do full refurb in one go but I think I'd rather do it in bits and less bothered about cosmetic look of the place to an extent but can only live with so many pipes exposed etc