Daniel Smith
hi Ivan Providing the outside tap you would like installed is on the other side of a cold water feed from inside i.e straight out from under the kitchen sink then this is a fairly straight forward job. you require a check/non return valve a length of 15mm copper, a few fittings and of course the outside tap its self if you haven't already purchased this based on the outside tap coming from under neath the sink you should expect to pay between £50-£100 i hope this helps Dan
