RIBA Pushing for Mass Retrofit


The Royal Institute of British Architects has recently issued a report urging the United Kingdom’s government to retrofit homes in England’s interwar suburbs.

The report, titled “Homes for Heroes,” calls for the creation of a national program to retrofit over three million homes built between 1919 and 1939. Most of the retrofits will focus on insulation, as the improvements are believed to help cut carbon emissions and tackle fuel poverty.

“Without reducing our domestic operational energy consumption, the U.K. will miss its net zero carbon target,” explained RIBA President Simon Allford. “There can be no further delay in embarking on a national program of home retrofitting, which will transform U.K. housing, creating warm and cheaper to heat homes while bringing health and wider societal benefits.”

Homes for Heroes

According to the report, what caused the recent retrofit initiative were observations made on the homes’ poor insulation, solid wall construction and high gas reliance which have led to much higher prices tags in terms of energy consumption. In 2021, it was found that 17% of households in interwar suburbs were in fuel poverty, proportionally higher than the overall national rate of 13%.

What’s more, is the carbon emissions released from the 3.3 million homes in the suburbs that have not yet been privately retrofitted currently account for 12% of the total 77 million tons of CO2 produced each year by the country’s housing.

In additional research, officials found that only 10% of interwar homes achieve an Energy Performance Certificate (EPC) above Band C. An EPC is a measure of the overall efficiency of a home, for which the best rating is A and the worst is E.

If current Band D rated homes were retrofitted to achieve Band C performance, households would save 483 pounds (about $658) per year under the 2022 energy price cap. The effort would also reduce England’s total carbon emissions by 4% and could play a key role in helping to meet the UK's 2050 net-zero carbon target, according to RIBA.

“Implementing decarbonization measures across homes in an area can catalyze wider change in community engagement and employment programs,” said Allford. “In light of recent gas price increases, moving to low-carbon heating such as heat pumps could make a significant difference to residents of interwar homes.”

To achieve these retrofits, RIBA has suggested a “fabric-first” strategy, involving the insulation of walls to effectively deploying heat pumps, and outlines effective funding mechanisms—from tax levers, to grants, to allowances for landlords.

The program is also slated to create 5,000 full-time, green jobs every year for the next ten years.

Homes for Heroes follows the RIBA's Built for the Environment report that it issued in collaboration with Architects Declare. The report sets out ways to decarbonize the industry and calls on governments to overhaul building codes to better regulate the energy performance of buildings.

Additional UK Retrofit Plans

Just a few months prior to RIBA’s announcement, the London Energy Transformation Initiative (LETI) released a Climate Emergency Retrofit Guide to aid in retrofitting homes throughout the U.K. to meet national Net Zero targets.

According to reports, the Climate Emergency Retrofit Guide was created with the help of more than 100 architects, engineers and building experts regarding best practices in home retrofitting and how existing homes can meet the U.K.’s Net Zero targets.

In looking at practical ways that homes could successfully meet approaching climate change targets, LETI identified specific energy uses and categorized existing homes into four different types (constrained or unconstrained): mid-terrace, semi-detached, detached and apartments.

The guide also sets out six key principles for retrofit best practices. Of them, the guide specifies creating a “whole house Retrofit Plan,” which must follow the LETI Retrofit Process:

  • Set out key building information, constraints, risks and opportunities;
  • Set out the key works proposed along with related strategies and details;
  • Set out the sequence of work;
  • Be appropriate in its level of detail and intervention for the project;
  • Include a plan for monitoring and reporting energy consumption; and
  • Stay with the building.

The guide is free to access and targets 60-70% total energy consumption reductions for the average home in the U.K. While the percentages could sound high to readers and retrofitters, LETI reports that its team of experts looked over the country's current housing stock, renewable energy production and grid capacity to define a realistic goal.

LETI’s level of retrofit reportedly closely matches the AECB Retrofit standard in terms of both space heating demand and final EUI. The best practice model is as follows:

  • Fossil fuel free home;
  • Energy use intensity of 50 kWh/m2/yr (with an additional 10 kWh/m2/yr for constrained retrofits);
  • Space heating demand of 50 kWh/m2/yr (with an additional 10 kWh/m2/yr for constrained retrofits);
  • Hot water demand of 20 kWh/m2/yr (with an additional 5 kWh/m2/yr for homes <75m2); and
  • Renewable energy where 40% of roof areas are covered in PV panels.

In addition to outlining retrofit options, the guide also touches on potential risks associated with poor retrofitting, such as building damage.

The guide is designed to be used by architects, engineers, Local Authorities, social landlords, energy professionals, contractors and clients.

Several organizations that have endorsed the Retrofit Guide include: the Royal Institute of British Architects (RIBA); Architects Declare, the Architects Climate Action Network; the UKGBC; and the Chartered Institution of Building Service Engineers.

A full copy of the guide can be viewed here.

LETI reports that following its recent publication, the organization intends to produce a separate retrofit guide for non-domestic buildings. Previously, in January 2020, the organization published a Climate Emergency Design Guide, which sets out requirements for new buildings to achieve climate targets. Since its publication, the document has been downloaded more than 60,000 times in 100 different countries.


Tagged categories: Carbon dioxide; Carbon footprint; EMEA (Europe, Middle East and Africa); EU; Europe; Good Technical Practice; Government; Maintenance + Renovation; Maintenance programs; Program/Project Management; Project Management; Renovation; Residential; Retrofits; Royal Institute of British Architects (RIBA)

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