The energy declaration will be an incentive for energy conservation. But the economical potential is perhaps more important for most owners. Saving energy can be very profitable.
Unfortunately to many consultants are using and suppliers are using non adequate tools (or even no tools at all) that gives unsatisfactory results.
Of course there are investment that are profitable enough to not need any calculations.
But generally you must get a picture of the buildings potential. The only reliable way is to make a calculation. Forget statistics and square meter values. Be skeptical to all who asks for square meters. Energy consumptions are dependent on building geometry, building physics, user behaviors, climate and installations. Selection of individual components can depend on factors that are unique for your building.
