Isolation Valves

[ck1]

I've got a cold water outlet under my sink which feeds the dishwasher via an isolation valve. I need to add a second isolation valve for a second appliance, is there such thing as a 'double isolation valve' with compression fitting or what would be the best way to attach a second isolation valve?

[The Builder]

I guess you mean a washing machine valve (same as dishwasher valve).
Simplest way is to keep your existing valve and use one of these.........

http://www.screwfix.com/p/washing-machine-y-piece-bsp/81000