Ying li panels 12 and an aurora inverter. internal insulation bubble foil battens,bubble foil air gap then 12mm foil backed plasterboard works as DIY project too costly if done by contractor. Optimal roof insulation. Would like to do more but cannot find anything that can be justified by cost. Will be taking all rainwater into victorian soakaway well soon will lead to a rebate on my Anglia water bill.
I have house in multiple occupation,my flat and five bedsits. I have internaly dry lined with bubble foil and tow air gaps this has helped to keep energy bills down to less than £1500 a year,given three kitchens and bathrooms i am satisfied. Hot water is by two gas multipoint brittony heaters. There are seven balanced flue baxi wall heaters most not used since insulation. I have looked at alternative heating systems but none work from a cost point of view. Condensing gas central heating would cost probably £7000 plus to install may use less gas but the heaters we have require no maintenance,one is forty years old and passes test every year and the multipoints will last 25 years...condensing boilers 12 years if your lucky!