Really low water pressure

There are a few variables so this is just a rough guide:

Normally if your kitchen sink tap has a good water flow the problem may be inside the property, also check if the bath has an issue as if the flow is reasonable it may be the pipework to the taps. If the flow to both is poor I would check that your "stop cock" in the road is fully open and also the tap usually located by the kitchen sink is fully open so you get the maximum water flow.

Some houses have a cold tank in the loft and a valve that is used for cold water (this is different to a hot water cylinder) check this has water and is not frozen or not working.

Speak with your neighbours and confirm that they usually have reasonable water pressure and if that is the case contact your water company.

Hope that helps.

If you have a good pressure downstairs the problem is in the house so a job for a plumber or yourself rather than the water supplier.

First thing to check is the filter inside the tap, it should (easily) screw off the front and hopefully will be full of muck that’s causing the trickle. Post a picture of your tap if you can’t figure out how to get the filter out & I will tell you.

Failing that -

I sorted a similar issue at my house yesterday. The flexible tap hoses had clogged up at the nut.

If it’s only the 1 basin having the issue, It may be worth checking there.

Picture isn’t the best as that’s the cold hose, the main issue was the hot but I went from 3lpm to 9lpm after clearing it.


(edited)

If all the other taps in the house are working fine the problem must be the tap itself (probably furred up) or there is a shut off valve somewhere along the feed pipe to the tap that is partially closed. It doesn't sound like the problem is anything to do with your water supply.

I will check the hose and pipe and let you know if that is the problem. Thanks

Is it direct from the mains or do you have a cold water tank (Nothing to do with a possible heating header tank) in the loft.

The VERY first thing to establish is if the sink is fed from the mains water supply directly or from a tank in the loft. There is no point talking to your water supplier in the first instance if it is the latter.
Nobody can give you advice without knowing this. (edited)

The sink is fed from mains water supply

OK, then if you have good pressure downstairs there is a restriction between the two. Do you live in a hard water area?

You say the taps in the bathroom, is there a loo in there as well, how quickly or otherwise does that fill?

At the risk of stating the obvious, this is only your problem if you are buying your property, not renting.

could be faulty basin taps. call an experienced plumber round.

Could be the taps. We purchased some new bath taps and the water was so slow coming through. Father in law sent them back and ordered some others which allowed more water through and were alot more powerful.

A lot of taps come with a reducer valve inside the tap housing, this restricts the flow to save water, usually fitted to bathroom sink taps, as a lot of people leave them running when cleaning teeth etc, and washing hands. You can check by taking the tap apart, and removing the plastic reducer.

Your flexible pipes to your sink taps should have their own isolator valve on each one.

As it an unknown try locating under sink, they should be easily accessible.

They will either be a flush style round circle with a slot for say a screwdriver to turn or a valve you can use with your fingers. Either way which ever option make sure that the slot line follows the line of the pipe or the valve ble/red follows the direction of the pipe, this will ensure both are open fully.

Google isolation valves so you know what you are looking for.

Stop playing the with mains stop cock, especially if you have a combi boiler and other people are in the house potentially going to be using hot water.