Electric to mixer shower

We're in the process of doing up our first house and are looking at changing from an electric shower to a mixer shower, which would be fed from the combi boiler in the kitchen downstairs. We recently had the house rewired and the shower is now completely disconnected from the electricity supply, which we thought would make sense given our intention to change to a mixer shower.

As the shower currently only has a cold water supply, additional piping will be needed for hot water. My question is this: is it possible for a plumber to take a hot water feed from the hot tap in the bath, or will a dedicated pipe from the boiler be required?

We've just had the kitchen re-plastered and pipework boxed in so we really don't want to start drilling holes etc. for additional piping if we can avoid it!

Thanks in advance for any advice.

Jerturn,
As unlikely that bath will be on at same time as shower, I see no issue having bath and shower off same hot water pipe.
In fact I bet many houses have this - one hot and cold water pipe to bathroom, supplying bath sink shower and toilet (cold only).
SFK

Yes, no reason why not.

if it is a combi boiler then yes no problem doing what you suggest

Thanks all for your responses - much appreciated.

Had a plumber round last night who suggested replacing the bath taps to include a hose extension, which would serve the same purpose without having to route new pipes into the wall. We'll be getting the whole bathroom replaced, re-plastered and tiled when we have the money, so this looks to be the quickest and most cost-effective option for now.