EPC Recommendations, Explained

EPC recommendations are a modelled list of measures that would improve the home's rating, generated from the assessor's data. Each recommendation, such as loft insulation, wall insulation, heating controls or glazing, appears because the model found a weakness it addresses. Each carries a modelled effect on the rating and an indicative cost range, and the list is ordered in a way that reflects the model's logic, not necessarily the best order for a real household.

The crucial point is that recommendations are generated, not designed. No one has checked, at certificate stage, whether wall insulation suits that wall, whether the heating system can accept a new control, or whether ventilation needs change. Recommendations are therefore a prompt for professional investigation, and the most valuable recommendation is not always the first on the list.

Recommendations work cumulatively in the model: each one is modelled as if previous recommendations were also carried out, so their individual effects cannot simply be added together. A recommendation modelled on its own may show a larger effect than the same measure shows after other measures have already reduced demand. Reading the list as independent savings, and adding them up, overstates the total.

Indicative costs are broad ranges for discussion, not quotations. They reflect typical costs at assessment, without site-specific factors such as access, heritage constraints, asbestos, or the need for ventilation work alongside insulation. A real quote for the same measure in a particular home can fall outside the indicative range for entirely legitimate reasons, and a quote inside the range is not automatically good value if its scope is thinner.

Rank recommendations by two tests, not one: modelled effect, and suitability for this construction. A high-effect recommendation that is unsuitable for a solid stone wall or a listed building should not outrank a lower-effect recommendation that can be done safely now. Ask a professional to check suitability, moisture and ventilation for each recommendation before any price is compared.

Check interactions between recommendations. Insulation recommendations interact with ventilation, heating recommendations interact with radiator sizing, and glazing recommendations interact with ventilation and solar gain. A recommendation that looks attractive alone may need companion work, and that companion work belongs in the same budget discussion, not discovered after the first measure is fitted.

In the UK, recommendations appear on the EPC itself, with modelled effects and indicative costs shown in the certificate format for the relevant nation. Scotland's format presents recommendations differently, with additional context, but the generated nature of the list is the same. A reader should not treat a Scottish recommendation list as a specification any more than an English one.

In EU member states, certificate recommendations vary more widely: some certificates carry detailed, costed renovation roadmaps, others carry a short list of generic measures, and some link to national renovation advice services. The EPBD recast encourages more detailed renovation information, but national implementation determines what a householder actually receives, so the depth of recommendations should not be assumed across borders.

One mistake is working through recommendations in printed order without questioning it. Printed order reflects model logic, which may place a disruptive, expensive measure before a cheap control improvement that would deliver comfort sooner. Reorder by suitability, disruption, and interaction, with professional input, rather than following the printout as a work plan.

Another mistake is treating indicative costs as a budget. A household that budgets exactly the indicative range, then receives quotes above it, may abandon a worthwhile measure, while a household that budgets the range as a ceiling may accept a thin-scope quote that omits ventilation or commissioning. Use indicative costs only to decide which recommendations merit a proper, site-specific quotation.

Keep the certificate recommendations page with notes on each: suitability checked, professional consulted, quote obtained, and decision made. That annotated list becomes a useful record for future owners, and it prevents the same recommendations being investigated twice without progress.

Ask a professional, for each recommendation you are considering: does it suit this construction, what moisture and ventilation checks does it need, what companion work does it require, and what evidence will be provided after installation. Clear answers to those questions turn a generated list into a real plan.