DIY Doctor UK DIY Forums

I have just moved into a 3 storey house with a old combi boiler. I would like a good hot water system to provide water to 2 showers and a bath. We have no loft space for gravity feed tank, and our mains cold feed is 15mm. Not great I know, it would be a mega job to replace with 22mm or bigger.
What system would do the job? We gave an old airin cupboard for a tank.
Advice please.......

I had a similar situation (1 bathroom, 2 shower rooms) but didn't use the W/Bosch combi boiler for everything (it really wouldn't have been able to cope). Instead it only services the taps in the kitchen and the bathroom. The two shower rooms use electric showers. This set-up seems to then allow a reasonable pressure to be maintained in all outlets.