Retrofit advice on improving the energy efficiency of historic buildings

We have produced a guidance document with information for improving energy efficiency and reducing CO2 emissions in historic buildings. This document also indicates whether different interventions will need planning permission or listed building consent.

Energy efficiency in historic buildings (2023) PDF

Retrofit, energy efficiency and historic buildings

Retrofitting Lewisham’s historic buildings in a sustainable way will help tackle the climate emergency. It can reduce heat loss, lower energy use, and support renewable energy.

These buildings are already sustainable. They are durable, can be adapted over time, and are built from materials that can be repaired and maintained, so they can last for a very long time. They also hold a lot of carbon from when they were first built.

However, the way they use energy can be improved. This will help keep them comfortable, healthy and affordable to live in.

There are many ways to retrofit historic buildings. The Council will support work that uses materials which are compatible with traditional building materials and protects the special character of the building or the conservation area.

Poorly planned or badly done work can cause damage. It may harm the building, affect people’s wellbeing, and fail to deliver the expected carbon benefits.

The importance of preventive maintenance

Preventive maintenance involves performing routine inspections and repairs. This helps stop your building falling into disrepair and avoids large, costly repairs later on.

For example, checking gutters regularly for cracks or blockages can prevent leaks. Fixing small problems early can stop them becoming serious issues.

Regular maintenance helps keep buildings in good condition.

Buildings in good condition that are dry, watertight and well maintained will need less energy to heat and run than damp, leaky buildings. Ensuring that the basic fabric (walls, roofs, doors, windows, chimneys) of a building is in good condition is the first step to preparing a project for energy efficiency improvements in a historic home.

The Energy efficiency in historic buildings (2023) advice note contains a list of small but effective actions that do not need planning permission or listed building consent, which homeowners can carry out to ensure their building is in good condition and using energy efficiently.

The Society for the Protection of Ancient Buildings (SPAB) also has a helpful calendar to remind you of small, easy maintenance tasks to carry out during the year to keep your building dry and in good condition.

The importance of a tailored, whole-house energy approach

Every historic building is different, and has aged differently over time. For that reason, some energy efficiency measures are more likely to be suitable or efficient for certain buildings than for others. For example, historic buildings with thick masonry walls are unlikely to lose heat through walls. However, they may benefit from draught-proofing to windows and doors, as well as loft and underfloor insulation, to ensure heat does not escape through other means.

Simple, regular maintenance can help most historic buildings. However, there is no single approach that works for all retrofit projects.

Each building is different. Retrofit work needs to be designed to suit the individual building and how it performs, including how it loses and retains heat.

A good retrofit starts with proper surveys, data and assessment. This helps build a clear picture of the building’s condition and energy performance. The right solutions can then be designed to improve energy efficiency.

Standard or ‘one-size-fits-all’ solutions are unlikely to work well and may not deliver the expected carbon savings.

This building-specific approach to energy retrofit is called a whole-house approach, and is recommended by Historic England. It ensures that the retrofit will be specific and tailored, leading to the most effective energy and cost savings.

Our Conservation Team recommend a whole-house approach to retrofit, and planning and listed building consent applications for large retrofit proposals will be asked to demonstrate that they have considered a whole-house approach.

More information on the whole house approach can be found on Historic England’s website: Whole Building Approach for Historic Buildings

The Sustainable Traditional Buildings Alliance (STBA) has a detailed advice note on what to consider when planning a responsible retrofit project in a historic building.

Where to find additional guidance and information

Historic England is England’s statutory adviser for the preservation of the historic environment. They have produced very useful guidance for homeowners wanting to improve the energy performance of their homes.

• Energy efficiency advice for homeowners: Energy Efficiency and Old Houses
• Retrofit advice: Energy Efficiency and Retrofit in Historic Buildings
• Technical Advice Note 18: Adapting Historic Buildings for Energy and Carbon Efficiency: Adapting Historic Buildings for Energy and Carbon Efficiency - Historic England Advice Note 18

The Society for the Protection of Ancient Buildings (SPAB) has produced technical advice notes on energy efficiency in historic buildings, covering subjects such as breathability and compatible insulation materials, floor, loft and rafter insulation, and general guidance on energy efficiency in old buildings: Search the Knowledgebase

The SPAB also runs a technical advice line to answer questions about the repair, maintenance and upgrading of energy efficiency in old buildings: Technical Advice Line

The Sustainable Traditional Buildings Alliance (STBA) brings together heritage, industry and sustainability organisations across the UK. It works to support a sustainable future for traditional buildings.

Their Responsible Retrofit Knowledge Centre is an online resource to help homeowners and retrofit professionals make informed decisions. It provides guidance and builds understanding of how to carry out responsible retrofit work on historic buildings.

The Responsible Retrofit Guidance Wheel is a detailed tool that supports a whole-building approach to retrofit. It shows how different measures are linked and highlights the key issues to consider for each type of work.