I am having a single-room extension built over my garage and need to decide on a heating system. Answers to similar queries in this forum all seem to advise extending the Gas Central Heating to provide radiators in the new room. British Gas advise that, because the existing boiler is over 13 years old and might not be capable of supporting the additional radiators, it would be better to replace it with a more modern and efficient one. This would require some re-routing of pipes and the total cost (excluding fitting out the extension) would be £3300. Given that the extension would be used occasionally rather than all-day/every-day, I am wondering if an electrical heating system might not be better. I have discounted electric storage radiators (ugly, hard to control and not good for evening use) and underfloor heating (wood floor) but what about modern, slim-line electric radiators with a good control system? I accept that the cost of electricity might be higher than for gas but I can buy an awful lot of it for £3300.