Retrofit Done Right

Retrofit Done Right

Retrofit is the process of making significant changes to an existing building to improve its performance in some way. This can involve a wide range of interventions, from upgrading the building’s energy efficiency to improving its accessibility or functionality. Most of the time people intend to improve energy efficiency so we’re going to focus on this here. Ways of improving the energy efficiency of a building are often phrased as an Energy Efficiency Measure [EEM].

Our preference is for a fabric first retrofit approach which means insulate, draught strip and upgrade the existing building fabric as much as possible.

When considering an extension or new build project something that is often missed is that an existing building may not need to be extended or a new building built from scratch to create the extra space desired. An existing building may just need to be reconfigured and remodelled. There is often the perception that more space is better but building more space costs more money and also costs more in environmental impact. We feel that trying to reduce our consumption of materials and energy is important. Key issue to consider is that we can often function perfectly well with the space we already have, albeit laid out slightly differently. Sometimes it’s better to remodel what’s already there than to build afresh. Retaining existing buildings and reusing as opposed to demolishing and rebuilding is often a more energy efficient way of doing things as the amount of energy used to build is reduced. This isn’t always the case and individual circumstances need to be considered on a case by case basis.

As a homeowner of a fairly typical 1930’s house, that was purchased in 2011, without any insulation and the original single glazed windows, we understand the costs, challenges and disruption that occurs when completing a retrofit project. We are part of the way through a phased, full house deep retrofit, not to Passivhaus / EnerPHit standards, mainly as we can’t afford to, but also the loss of internal room space taken up by internal wall insulation is too big. There is already a large reduction in energy use, energy is being monitored and recorded each month. Other big benefits that have been observed, is that occupant comfort and health levels have increased, as the building retains heat for longer, super important ventilation is controlled, which means the house is nicer to live in. It really does make a difference.

Unintended consequences and PAS 2035

When remodelling and reconfiguring existing spaces it’s really important these are improved with energy efficient upgrades as part of a coherent and well considered, holistic retrofit strategy. You need to look at the entire building or space to ensure everything is thought through. Ideally, don’t just focus on a small part of a building or space but rather the entire building or space. There are often easy ways to upgrade parts like exposed floors, walls, roofs, glazing, unused chimneys and working out ways to reduce unwanted drafts, as part of a remodelling project.

With any retrofit project there are risks. Sometimes adding in Energy Efficiency Measures can create unintended problems, such as damp and condensation issues + several other problems. If an entire building or space isn’t considered as a whole and the risks not understood and dealt with appropriately irreversible damage to the building fabric can occur and a poor quality environment created which can affect occupiers health and wellbeing.

PAS 2035 / 2030 is the recommended standard for retrofitting to dwellings and is published by the British Standards Institution. At the moment PAS 2035 / 2030 is not mandatory for private dwellings but it is mandatory for public dwellings such as social housing etc. It is likely it will probably become mandatory in the future for private dwellings but will likely be difficult to control and police. As full CIAT members we automatically qualify as Designers under PAS 2035 but not for older, traditional buildings with solid walls and without modern damp proofing methods. These types of building behave very differently to modern sealed buildings and need to be approached differently, and the different risks understood. Further study and a separate qualification is required to be a certified PAS 2035 Designer for older, traditional buildings. We are pleased to report that we have recently [July 2024] achieved the PAS 2035 Level 3 Award as a Designer in Energy Efficiency Measures for Older and Traditional Buildings. It’s likely that PAS 2035 will become mandatory at some point over the next few years and being able to provide services that align with the intention of PAS 2035, for all building types and Clients is well worth doing.