As above, just been decorating my downstairs cloakroom. I've replaced the toilet and sink but since replacing the sink I seemed to have lost water pressure from the hot tap.

The old sink had individual hot / cold taps and although the pressure from the hot wasn't as good as the cold it was fine for washing hands etc..... However, I've put a mixer tap in there now and a lot of the pressure has been lost.

Now the only other changes / alterations i've made to the pipework is that i've added an extra isolator on the pipes, due to the location of the sink it was difficult getting to the original one so I've kept it in place (fully open) but put another one further up the pipe. Would this make a difference on the pressure going to the tap? The pipe is standard 15mm copper and have used speedfit connector to route it. Someone has advised to possibly put a gate valve(?) in place rather than an isolator as it doesnt restrict flow when open?

I'm by no means a plumber so feel free to shoot me down!!

Cheers
Chris