Almost started taking up all the new flooring this today. Turned on the tap this morning and noticed the water pressure was low. After all the work my first thought was we had a leak under the floor. Arrrghhh. After pulling out the washing machine and emptying two cupboards and calming down a bit I phoned the plumber who thought it strange and asked if any of the neighbours had the same problem. Turned out the the whole area was the same.
Glad I checked before ripping it all up.