Visited a 3 year old Wimpy house where the customers have a problem with the cold water flow in their two en-suite showers. They said that since the house was built they were'nt happy with the flow but now the cold is just a 'trickle'. Both showers are gravity fed (hot & cold) with no pump. The feed from the header tank enters the airing cupboard and T's off to 15mm under the floor boards to travel I should imagine 6 metres to get to each en-suite. The hot supply is 15mm from the storage cylinder as well. When I visited I did'nt have any tools as I was in my car and just went to have a look so nothing checked physically. Is this purely a bad design and any ideas for remedy.