Economically feasible
Approved Document L, Conservation of fuel and power, Volume 1: Dwellings, 2021 edition incorporating 2023 amendments, states in relation to the term ‘economically feasible’:
The capital cost of a measure will be recouped in energy savings within a reasonable time. For the purposes of this document, economically feasible means that the measure would achieve a simple payback after one of the following.
- 7 years, for the installation of thermostatic room controls.
- 15 years, for any other measure.
Volume 2 defines it as when:
The capital cost of a measure will be recouped in energy savings within a reasonable time. For the purposes of this
document, economically feasible means that the measure would achieve a simple payback after one of the following.
- 7 years, for the installation of thermostatic controls.
- 7 years, for the extension of on-site low and zero carbon energy-generating systems which are required as consequential improvements (see Appendix D, Table D1).
- 15 years, for any other measure.
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