stopcock / removing kitchen sink

[phantos02]

Hi Folks

I have no plumbing knowledge to speak of so appreciate any advice...

I need to gut my kitchen ready for re-wiring, re-plumbing, plastering, and fitting of new units, this will obviously involve disconnecting the existing sink. Is it sufficient to turn off the water supply to the sink only at the mini valves supplying the mixer tap (believe I can just do this with a spanner, doing a quarter turn?) or is it essential to turn off the water supply altogether at the mains first?

The reason I ask is because the mains stop-cock tap under my hallway floor seems to turn and turn but the water will not go off. So I don't want to have to pay a plumber twice IYSWIM, once to fix the stopcock and a second time to do all the rest of the plumbing for the kitchen. I'm thinking it would be better if I could remove everything I need to in the kitchen first and then have one visit, during which he can fix the stopcock.

Sorry if it's a stupid question!!

 

[Softus]

Is it sufficient to turn off the water supply to the sink only at the mini valves supplying the mixer tap

It's quite sufficient as long as they work.

(believe I can just do this with a spanner, doing a quarter turn?)

Er, I can't match your description to any valve I've seen.