EPC Scotland | Property Certificates

WHAT ARE THE DIFFERENCES BETWEEN SCOTTISH, ENGLISH & WELSH EPC RATING SYSTEMS?

Regional variations in the methods used to calculate Energy Performance Certificate (EPC) ratings can often lead to confusion.

It's important to recognize that EPCs generated in different regions, such as Scotland and England, cannot be directly compared without considering additional information beyond the headline rating.

One significant difference lies in the approach to calculating the asset rating. In England and Wales, the EPC system derives the asset rating from a ratio of the Building Emissions Rate (BER) and Standard Emission Rate (SER).

This process involves multiplying the SER emissions of a reference building by 50 and then using a self-referencing linear scale to determine the associated band. The scale ranges from B to C with a fixed boundary at 50, and the top of the A scale is set at 0. The upper limit for this rating system is 150, but it is important to note that this is not a linear carbon scale, unlike the approach used in Scotland.

Conversely, the Scottish rating system calculates the numeric asset rating directly from the BER in kgCO2/m2 and assigns the associated band using a straightforward linear carbon scale from A to G, ranging from 0 to 100.

As a consequence of these differing calculation methods, buildings in Scotland often achieve lower ratings compared to similar buildings in England. This disparity may lead investors to favor England in their investment decisions. To make a fair comparison, it is crucial to look beyond the headline rating and consider the underlying energy usage.

The potential for misunderstanding arises when comparing buildings from the two regions solely based on their headline ratings. Sometimes, a building in Scotland may receive a lower rating than an equivalent building in England, which might mistakenly lead one to assume that the English building is more energy-efficient. In reality, a more accurate and representative comparison can be achieved by comparing the BER values rather than relying solely on the headline rating.

Advocates of the Scottish approach argue that it provides a clearer indication of a building's energy (and carbon) performance since it directly uses the absolute carbon figure for the rating. On the other hand, some find the relative rating system employed in England and Wales difficult to comprehend.

Understanding the nuances of these regional differences is essential for accurate and meaningful EPC comparisons.