Hi,

Either I am really stupid, or tumblr really doesn’t show the date when a message was sent. So, if it has taken me ages to reply to your message, then apologies.

To answer your question, if you are doing a major renovation, you should add about 25% to the total cost for energy-related measures. If you are not doing work anyway, then this turns into 100% and then it depends on all sorts of things like size of house, finish/spec etc.

The key question is how deep a retrofit would you be interested in doing? You don’t need to retrofit to passivhaus to considerably improve the comfort in your home and reduce your bills.

If you would like to find out more about some of the less extreme projects we have worked on, feel free to drop us a line on info@greentomatoenergy.com.

Tom