Tighting taps under kitchen sink doesn’t cut off water supply

taps

I have a set of taps similar to these under the kitchen sink that lead to a single mixer tap.

taps

My issue is when I try to turn off the water supply via these (trying both directions) it still flows strong, not a leak/drip but as if the taps don't actually have a full closed state.

Can this be possible would the taps only be for adjusting pressure?

(If not) Should I try to force the taps further, or is there a risk of doing more damage?

Or should I use the main water shut off (which is harder to get to in my appartment building)?

Best Answer

Those are supposed to be shutoff valves, but they are usually very cheap and I would not be surprised if the rubber washers are more like bricks.

If you need to do tap maintenance you will need to turn off the apartment's water. Unless you are in a condo this is really the building owner's job, not yours.

I stopped using this style of shutoff ages ago. You can get mini ball valves that are much better in every way for very small extra cost.