What are VolDECs?

DSC_0083VolDECs (Voluntary Display Energy Certificates) are a new and innovative voluntary operational energy performance rating scheme for non-domestic buildings. Initially designed for commercial office buildings these are now being developed for other sectors. The ratings are based on relatively simple data, making them inexpensive and quick to produce.

VolDECs have been developed as commercial office buildings don’t have an appropriate means of measuring and highlighting energy performance in a relatively simple and consistent way. In particular, there are issues associated with the landlord and tenant energy split and the lack of relevant benchmarks to enable performance to be measured and compared sensibly and consistently.


Our VolDEC approach

Our new approach separates tenant energy use from that of the landlord and the common parts of the building (with the data being displayed either individually or on the same certificate). This provides property owners and operators with cost-effective, user-friendly energy ratings for areas of a building that they control or manage, and are able to improve.



Left – Whole Building (Landlord only) VolDEC – download sample certificate

Right – Landlord-Tenant VolDEC – download sample certificate


VolDEC methodology

DSC_0079Based on mandatory Display Energy Certificate (DEC) methodology and making use of relatively simple data, the scheme allows energy managers to easily and inexpensively identify the energy performance of their building(s) relative to other buildings they operate or others in the same sector. VolDECs also use more granular benchmarks than statutory DECs to give a more robust rating for performance.

The VolDEC story so far

The VolDEC story so far has been summarised in a paper and presentation ‘The Development of a Voluntary DEC Rating Scheme’ that the team presented at the CIBSE Technical Symposium in 2015.

Partnership project

The VolDEC scheme was originally developed by a working partnership between the National Energy Foundation and Phil Jones of Building Energy Solutions. Subsequently Carbon Descent took over NEF’s role and developed the webplatform version of VolDEC.