Comfortable, warm homes that don't cost the earth

The 21st century homes event up in Muswell Hill last weekend was attended by around 100 people. There was a chance to hear from home owners who have improved the insulation of their homes, installed solar panels to produce electricity and/or to heat water and replaced their windows or boilers.  Local installers and suppliers were also on hand to talk about their services. On Sunday around 50 people made visits to local houses where some of these measures had been carried out.

Could the ladder host a similar event?  Are there houses that have substantially reduced their heating bills?  I would love to hear from you.