We would like to be as eco-friendly as we can afford for the new house.
The frame incorporates a lot of insulation, but we will be adding more on the inside, with triple glazed windows to make the house as air-tight as possible. Ventilation will be provided by a whole house Mechanical Ventilation & Heat Recovery system, minimising heat loss while providing a comfortable environment.
There will be an air-source heat pump with under-floor heating, and a small wood burner in the living room for those extra cold days.
We would love to have PV panels on the roof, but do not think our current budget will stretch to it. However, the wiring will be put in during the build so that it can be retrofitted later with minimum disruption.
Update October 2013 - we have all the above, including the PV panels, paid for out of the VAT refund.