Shower option in attic ensuite

I'm converting my attic and having an ensuite installed. I was hoping for an electric shower with integrated pump ie Triton T90 but as the tank is lower than the shower, the plumber said this option wasn't possible and has suggested putting in a T80. My sister has a T80 and it's pretty useless. Another option is to have a negative head pump installed. Could this only be installed for the shower in the attic ensuite or will it have to be hooked up to the rest of the house's showers, etc. Any recommendations?

Your plumber has adviced you correctly.

The negative head pump can be piped just to that shower and hot water to WHB,(I assume you will have hot water at tap). You could get cold water from mains.

negative head pump and shower is much more expensive than an electric shower.

You may need pump to get hot water to tap or use a mains fed undersink water heater.

Thanks DaveyJones. Would it mean then having a switch to activate the pump in the hot press or would the pump come on automatically once the power shower is activated?

You would have a fused spur (switch) servicing the pump. the pump should have a constant live. The pump has built in flow switchs that will detect the movement of water (when you turn on shower) and activate pump. So it would be automatic.