Many historic buildings are designed to function in ways that can conflict with modern construction methods and standards. Due to a lack of understanding, work on these structures can inadvertently cause lasting damage if not undertaken correctly. At StudioFolk, we have handled numerous historic building refurbishments and have seen these issues arise again and again. In many cases, the problems we encounter could have been entirely avoided had the work been properly planned and executed.

This article highlights some of these issues to assist those planning energy-efficient renovations, thermal improvements, or other architectural work, particularly in listed building conservation, renovations, or extensions to historic buildings.

The Urgent Need for Retrofitting

With 80% of the buildings that will exist in 2050 already built, and existing buildings accounting for 17% of the UK’s carbon emissions, retrofitting is a critical part of the effort to reach net-zero.

Historic buildings, often predating modern regulations, typically suffer from poor insulation, single-glazed windows, and outdated heating systems, making them significant contributors to the UK’s energy consumption and more challenging to retrofit. Improving their thermal performance through retrofitting can reduce energy consumption by up to 60%, leading to substantial cost savings and lower carbon emissions. However, such projects require a skilled approach to preserve the character and integrity of these structures, especially in listed building conservation, historic building restoration, or when working within conservation areas and other protected sites.

StudioFolk_Historic Building Refurbishments_Listed Building Renovation — Listed buildings are protected in their entirety, so require a considered approach to retrofitting.

Key Considerations for Retrofitting Historic Buildings

Retrofitting a historic building is not a one-size-fits-all process. Therefore, it is always advised to first seek advice from a qualified professional. Many organisations, including us at StudioFolk, will offer free initial advice to ensure projects start on the right foot. Each building presents its own set of challenges and opportunities, and several factors must be carefully considered before undertaking works:

1 Understanding the Building’s Fabric and Heritage

Every historic building is unique, with its own materials, construction techniques, historical significance and protections. Before starting any retrofit project, it is essential to conduct a thorough assessment of the building’s fabric. This includes understanding whether it is a listed building, how the building was originally constructed, identifying any existing issues such as dampness or structural weaknesses, and recognising the features that contribute to its heritage value.

Many home renovation or home extension projects will face similar issues, such as dampness caused by lack of maintenance, brickwork defects, or inappropriate products used for previous building works. In such cases, an experienced architect should be able to identify and address these issues. For more significant projects like heritage building restoration or listed building conservation, we work closely with specialist historic building surveyors to get a detailed overview of the existing structure and identify issues that may be hidden within the fabric of the building. It is important that all existing latent issues are addressed, or at the very least known, before any additional works take place. In our experience, missing out this key step is the number one source of issues we come across.

2 Balancing Energy Efficiency with Heritage Conservation

One of the key challenges in retrofitting historic buildings is striking the right balance between enhancing energy efficiency and preserving the building's character and fabric. For instance, adding insulation to walls or replacing windows can improve thermal performance but may also negatively impact the building's condition, appearance, and historical value if these works are not sensitively undertaken. Listed building protections, as well as restrictions in certain conservation areas, often limit the extent to which prominent features can be altered, a topic we explore further below.

Modern materials, typically designed to be impermeable, water-resistant, and airtight, must meet high-performance standards set by modern building regulations. However, many historic buildings are constructed with solid wall construction that relies on a certain level of air and vapour permeability to function properly. Adding an impermeable layer to either side of a solid wall can hinder air movement, restricting the wall's ability to dry after wet weather. Additionally, improperly specified insulation—such as in roofs—can increase the risk of condensation within the structure. Both issues are often hidden and can become complex and costly to address if discovered too late.

Aesthetically, modern insulation often needs to be thick and installed around or within existing structures to comply with current regulations. This requires careful consideration and detailing to ensure historic features are not impacted, and consistent thermal performance throughout the building, minimising cold bridging, condensation, and temperature variations.

Every building is unique, and at StudioFolk, our team is experienced in tailoring innovative techniques and materials to provide the necessary thermal improvements without compromising the health or integrity of the building.

3 Navigating Planning and Regulatory Requirements

Retrofitting historic buildings often requires navigating a complex web of planning permissions, listed building consents, and regulatory approvals. This process can be daunting, but it is crucial to ensuring that the retrofit is legally compliant and respects the building’s heritage status.

One frequently occurring issue is the confusion over whether other existing parts of a building need to be upgraded to modern building regulations as part of the proposed works. This is because whilst all new elements (windows, insulation doors etc.) should meet modern standards, in many cases the remainder of the existing historic building will not meet these standards – for example, thermal performance of walls, or the size and arrangement of a staircase.

The building regulations are wide-ranging and cover everything from accessibility, thermal performance, ventilation, and fire safety, so ascertaining exactly what the requirements are can be complex and will vary depending on the scope of the works being undertaken. The simplest approach is to seek professional advice from a suitably qualified architect to support this and establish the requirements at an early stage. This is particularly true for listed buildings and scheduled monuments where their protected status will sometimes be in conflict with the building regulations requirements, limiting the extent to which wider upgrades can be made. This requires close liaison and agreement with the relevant conservation officer and building control authority to agree on an acceptable way forward.

At StudioFolk, we aim for a best practice approach to building regulations compliance, often advocating for compliance beyond the standards set out in the regulations, and we take a ‘whole building’ approach when we design. This means that we carefully consider the impact of our interventions on the performance of the building as a whole and actively seek cost-effective opportunities to improve the quality and internal living environment. We have a track record of guiding clients through this process, ensuring that all necessary permissions are obtained and that the project complies with both local and national regulations. Our deep understanding of planning policy, and our collaborative approach to design, allows us to anticipate potential challenges and address them proactively from the outset.

4 Sustainability and Long-Term Performance

Sustainability is a fundamental part of a successful retrofitting project. It’s not just about reducing carbon emissions in the short term but also about ensuring that the building performs well over its lifetime. This means designing for durability, minimising environmental impact, and potentially ensuring works can be easily reversed or replaced in the future.

There are a number of factors that impact the life of a material. When selecting materials, it is important to consider both durability and suitability for its context. For example, selecting appropriate materials for rooms with higher humidity, such as bathrooms and basements, or finishes that are breathable to prevent flaking or hard wearing in areas of high traffic.

Local ecology should also be considered when selecting materials, such as insulation that is resistant to rodent damage. If early ecological surveys indicate that bats or other protected species may be present in the area, alternative products and detailing may be required, such as bat-friendly roofing membranes.

At StudioFolk, we design with a 100-year timeframe in mind. This means that where possible, we select natural products with long lifespans such as stone, ceramic and timber, ensuring robust detailing to prevent unnecessary weathering or decay. With all of our projects, but most importantly for our listed building or scheduled monument work, we ensure that our interventions are reversible where possible, to allow for future change and adaptation.

StudioFolk_Studio Craft_Historic Building Refurbishments_Listed Building Renovation — Consideration of the durability and adaptability of materials during the design stage.

During our design process, we also work closely with conservation officers and heritage consultants to ensure that any interventions are in line with best practice conservation principles and guidelines. An example of this is guidance produced by the Society for the Protection of Ancient Buildings (SPAB), as well as organisations such as Historic England, who have recently released guidance on ‘Adapting Historic Buildings for Energy and Carbon Efficiency’ (July 2024), providing valuable insights for those undertaking retrofit projects.

How StudioFolk Can Help

Retrofitting historic buildings is a complex and nuanced process that requires a deep understanding of both architecture and heritage conservation. At StudioFolk, we pride ourselves on our ability to deliver high-quality retrofit projects that enhance the energy efficiency of historic buildings while preserving their character and significance.

Our team of London based architects is dedicated to working closely with our clients to develop bespoke solutions that meet their specific needs. We work across London and the surrounding areas such as Kent, Surrey, Berkshire, Buckinghamshire, Sussex, Oxfordshire and Hertfordshire. Whether you’re looking to retrofit a Grade II listed townhouse or a historic commercial property, our experienced team can guide you through every step of the process.

Get in Touch

If you’re considering a retrofit project, we would be happy to discuss it with you and provide advice. Visit our contact page or get in contact with our team via our email address - hello@studiofolkarchitects.com

How to Renovate Historic Buildings