Top 10 Retrofit and Decarbonisation Companies in the UK (2026)

Wates is one of the UK’s established construction and property-services organisations and has developed an end-to-end retrofit service focused heavily on social housing.

Its retrofit model supports housing providers with early project planning, funding preparation, property analysis, design, compliance and delivery.

Wates has publicly described its retrofit solution as PAS 2035 compliant and designed to help housing organisations progress towards long-term carbon-reduction objectives.

The company has experience delivering external wall insulation, loft insulation, low-carbon technologies and other energy-efficiency improvements across housing portfolios.

Wates may be particularly relevant to councils and housing associations requiring a contractor with the resources and supply-chain capacity to manage large numbers of properties.

EQUANS provides energy, regeneration and decarbonisation services for public-sector organisations, local authorities and housing providers.

Its retrofit support can begin before physical installation. Services may include feasibility studies, funding support, identification of suitable properties, energy and carbon analysis, net-zero planning and project delivery.

EQUANS describes its service as an end-to-end model covering the process from initial funding applications through to implementation.

The company has experience supporting large housing programmes where project governance, resident communication, reporting requirements and delivery across multiple properties are essential.

Its scale and broader energy expertise may make it suitable for public-sector clients requiring strategic support alongside practical installation.

Morgan Sindall Property Services delivers property maintenance, housing improvements and decarbonisation programmes across the UK.

The company works with councils and housing providers to improve the energy performance of existing homes through measures such as insulation, solar PV, low-carbon heating, ventilation, energy-efficient lighting and building-fabric improvements.

Its programmes can cover large numbers of properties and combine technical delivery with resident communication, compliance and project reporting.

Morgan Sindall Property Services may suit organisations requiring structured delivery across large housing portfolios while maintaining a resident-focused approach.

Mears Group provides housing management, maintenance and energy-improvement services across the UK.

Its retrofit capability includes assessment, design, coordination, building surveying and installation support. The company also works with PAS 2030, TrustMark and MCS-related delivery requirements through its internal teams and wider supply chain.

Mears combines retrofit work with its experience in housing maintenance. This may help housing providers coordinate energy upgrades alongside existing property repairs, planned maintenance and resident services.

Its project experience includes insulation, replacement windows and doors, ventilation improvements, solar PV and heating-efficiency measures.

Bell Group provides property, energy-efficiency and retrofit services throughout the UK.

Its retrofit offering includes assessments, coordination, insulation, ventilation, solar PV, air source heat pumps and other low-carbon technologies.

The company states that its retrofit services follow PAS 2035 principles and include qualified professionals across assessment, design and coordination roles.

Bell also places emphasis on resident engagement and communication. This is important when energy-efficiency improvements are carried out in occupied housing, where access, disruption and correct use of new technologies must be carefully managed.

Sureserve provides energy, compliance and low-carbon services to housing associations, local authorities and public-sector organisations.

Its retrofit services include planning, insulation, renewable heating, solar energy, ventilation, funding support, monitoring and aftercare.

Sureserve states that it has in-house retrofit coordinators and assessors and can manage multiple stages of the retrofit process. Its approach prioritises building-fabric improvements before additional low-carbon measures are introduced.

The company may suit housing organisations looking for a provider that combines retrofit installation with long-term energy services, monitoring and maintenance capability.

Sustainable Building Services specialises in residential retrofit and decarbonisation projects.

The company works with social housing providers, private landlords and homeowners and delivers whole-house schemes using PAS 2030 and PAS 2035 processes.

Its services cover retrofit planning, project delivery, energy-efficiency improvements and support for government-backed housing programmes.

Sustainable Building Services may be relevant to local authorities and housing organisations requiring a specialist contractor focused specifically on residential energy performance and decarbonisation.

Cardo Group provides housing maintenance, compliance, asset-management and retrofit services.

Rather than treating energy improvements as completely separate projects, Cardo integrates retrofit into wider property investment and long-term asset-management strategies.

Its services consider insulation, ventilation, heating systems, glazing, energy performance, planned maintenance and resident needs.

Cardo states that its approach includes PAS 2035 compliance, resident communication, performance monitoring and alignment with wider property-maintenance programmes.

This approach may suit housing providers that want to coordinate energy improvements with planned repairs, compliance works and longer-term housing-stock investment.

E.ON is widely known as an energy company, but it also supports energy-efficiency and retrofit programmes across the UK.

Its services include support with government-backed energy schemes, property upgrades and access to accredited installation networks.

Depending on programme eligibility and property requirements, improvements may include insulation, heating upgrades and other energy-efficiency measures.

E.ON provides retrofit support for homeowners and works with local authorities and housing providers on larger energy-improvement programmes.

It may be a suitable option for clients primarily looking to explore funding eligibility or access energy-efficiency improvements through a large national organisation.