Looking to install new heaters in our 2 bedroom flat. The spaces to be heated are as follows: - 1 double bedroom - 1 single bedroom - 1 medium sized (about 30 sqm) open lounge/dining/kitchen space We need the heaters to be as energy efficient and cost effective as possible. The flat is north facing and at ground level, so we've got also a damp issue that needs to be tackled with the new heating system.