Designing out unintended consequences when applying solid wall insulation FB 79
BRE (Building Research Establishment) is an independent, research-based consultancy, testing and training organisation, operating in the built environment and associated industries.
On 31 March 2016, BRE published Designing out unintended consequences when applying solid wall insulation (FB 79), written by Colin King and Caroline Weeks.
The guide points out that around 80% of the existing housing stock will still be in use in 2050, and so if we are to achieve targets to reduce carbon emissions, it is important that efforts are made to improve the performance of these buildings. Refurbishing solid walls with externally or internally applied insulation can help reduce heat loss, but it can also cause problems such as condensation and mould growth if it is not installed correctly.
FB 79 provides advice about how to assess potential risks and reduce the likelihood of long-term problems, including:
- Surveying and assessing risk and existing ventilation.
- Detailed design.
- Quality assurance on site.
- Adopting an integrated approach.
The 24 page guide is intended for surveyors, designers and installers, but it will also be useful for clients and householders, helping ensure expectations are realistic as they commission an appropriate team of professionals to undertake installation.
Its contents are:
- Introduction and background.
- Types of unintended consequences.
- Causes of potential problems with solid wall insulation.
- Tackling the causes of unintended consequences.
- Conclusions.
- References.
[edit] Related articles on Designing Buildings Wiki
- BRE and Willmott Dixon project to retrofit of a 1920s semi-detached house.
- BRE articles on Designing Buildings Wiki.
- BRE Buzz articles on Designing Buildings Wiki.
- Building Research Establishment BRE.
- Cavity wall insulation.
- Cold bridge.
- Condensation.
- Floor insulation.
- Insulation specification.
- Insulation.
- Roof insulation.
- Solid wall insulation.
- Solid Wall Insulation: Unlocking demand and driving up standards.
- U-value.
- Wall insulation and moisture risk.
[edit] External references:
- Reducing thermal bridging at junctions when designing and installing solid wall insulation (FB 61).
- Conventions for calculating linear thermal transmittance and temperature factors (BR 497, 2nd edn).
- Understanding dampness (BR 466).
- Thermal insulation: avoiding risks (BR 262).
- Fire performance of external thermal insulation for walls of multi-storey buildings (BR 135, 3rd edn).
Featured articles and news
UKCW London to tackle sector’s most pressing issues
AI and skills development, ecology and the environment, policy and planning and more.
Managing building safety risks
Across an existing residential portfolio; a client's perspective.
ECA support for Gate Safe’s Safe School Gates Campaign.
Core construction skills explained
Preparing for a career in construction.
Retrofitting for resilience with the Leicester Resilience Hub
Community-serving facilities, enhanced as support and essential services for climate-related disruptions.
Some of the articles relating to water, here to browse. Any missing?
Recognisable Gothic characters, designed to dramatically spout water away from buildings.
A case study and a warning to would-be developers
Creating four dwellings... after half a century of doing this job, why, oh why, is it so difficult?
Reform of the fire engineering profession
Fire Engineers Advisory Panel: Authoritative Statement, reactions and next steps.
Restoration and renewal of the Palace of Westminster
A complex project of cultural significance from full decant to EMI, opportunities and a potential a way forward.
Apprenticeships and the responsibility we share
Perspectives from the CIOB President as National Apprentice Week comes to a close.
The first line of defence against rain, wind and snow.
Building Safety recap January, 2026
What we missed at the end of last year, and at the start of this...
National Apprenticeship Week 2026, 9-15 Feb
Shining a light on the positive impacts for businesses, their apprentices and the wider economy alike.
Applications and benefits of acoustic flooring
From commercial to retail.
From solid to sprung and ribbed to raised.
Strengthening industry collaboration in Hong Kong
Hong Kong Institute of Construction and The Chartered Institute of Building sign Memorandum of Understanding.
A detailed description from the experts at Cornish Lime.
























