Cold water tap in bathroom

[Booldawg]

The bathroom sink tap has never been very good in its flow rate since we moved to the house in December. It has now got steadily worse and the water is barely trickling through. The tap is fed by the tank in the loft. Maybe there is a blockage that has got considerably worse? The cold water tap on the bath is fine, so I'm guessing that is fed by the main domestic supply.

[Hamish]

If you are connected to the domestic water suppy in the UK you cold water should not come from a tank in the loft. Get a plumber to come and look at it as you will be drinking stale water. Hot water is often supplied this way. Turn on the hot/cold taps and listen for the tank filling.

It is possible that the tap/pipe has become blocked up with lime scale - where do you live? is it a hard water area? (ie do you have trouble getting foam with soap)

[ck1]

I recently had a similar problem, the kitchen tap (which is fed from the mains supply) was fine but the other taps (fed from the loft) gradually stopped working over the space of a day. I have these little screw-off filters on the taps which make the water come out 'foamy', some residue from the tank in the loft had got into the system and ended up in these filters stopping the water coming out. Assuming you have similar taps this might be an easy place to start before paying �300 for a plumber like I did!

[buildersmate]

Hamish's comment about bathroom taps not being connected from the cold water tank is not correct - it is permitted (thought not a great idea). Ckl's diagnosos is almost certainly correct - limescale gradually blocks up the end of the tap where the water drops out because of gradually evaporation of droplets containing a bit of limescale every time you use the tap. Its much worse if you have those little in-line filters at the tap end that make the water appear to 'foam' as it comes out. Just have a clean them out every now and again. A water softener unit will help, but not justifiable to solve this problem alone.

[Booldawg]

Thanks for the answers. I've always been under the impression that the cold water in bathroom sinks is supplied by the tank in the loft as I remember always been told not to drink it as it will be stale. I'll start by cleaning out the tap filter. This seems to only be a problem with the cold water tap, maybe the hot water dissolves the lime as it flows ?