Every new build we quote includes an energy specification, and clients always ask the same question: which upgrades are worth paying for?
Airtightness first. It is the cheapest thing on the list and the highest returning. Tape and membrane cost a few hundred dollars and cut heating demand more than any single product you can buy.
Insulation second. Going from code minimum to a continuous exterior layer typically pays back in six to nine years in this climate.
Windows third. Triple glazing is a genuine comfort upgrade, but on payback alone good double glazing plus airtightness usually wins.
Heat pumps fourth. Only once the envelope is sorted. A heat pump in a leaky house is an expensive way to be cold.
Solar comes last, not because it is bad but because it makes far more sense on a house that needs less energy in the first place.
