We wish we had done this years ago. Our power bill has halved!, Our house is dry and warm. People keep asking what heating we are using as its an old Villa but totally warm now. The heatpump only needs to be on 18 now instead of 26 as the air is dry, and the place only takes moments to heat.
I would recommend any older drafty villas that have not had this service, to make it a priority 🙂