It appears there are two major ways to reduce energy consumption of buildings from fossil fuels:
- Renewables are to be part of the consideration when planning a new build and have become mandatory.
- Building regulations have been tightened to improve energy efficiency of all constructions.
Where the chicken or the egg comes in, is where the two issues are off balance.
To require excessive installation of alternative technologies on a construction while its insulation level is suboptimal is a waste of resources, money and energy; its impact turns out to be dramatic once the lifespan of such a wrong decision becomes part of the consideration > footprint.
Modern, existing and proven insulation and construction technologies allow energy reductions of 70 to 90% compared to existing regulations which is far beyond what current building regulations require. However, once those highly efficient technologies are implemented the decision requirement to use “renewables” on such a construction, be it PV, solar, heat pumps, wood chips, etc. comes much easier because the cost impact of such devices will be less dramatic: It is a simple fact that demanding less energy reduces the necessary scale of investment into alternative energy generating devices.
Of course and very important, it reduces running cost, it lessens emissions, it improves comfort and well being. Now, who would mind all that?
Consequently, even though building regulations do not cover what is possible it makes sense to go way beyond such requirements and make up for that in the long run; in this case I believe it is the egg that should come first.