GBIS – Great British Insulation Scheme, Nationwide

Measured across our retrofit programmes

  • 2,493homes with a post-works EPC
  • +11average SAP points gained
  • D → Caverage band movement
  • 99.6%finish at band C or better

Crawford & Co assessed and coordinated these homes. Figures cover every programme where works are complete and a post-works EPC has been lodged, September 2026, and are not specific to this project.

Overview

Crawford & Co Surveyors provides retrofit assessment and coordination under the Great British Insulation Scheme, which funds a single insulation measure in less efficient homes across the lower Council Tax bands, in both owner-occupied and rented tenures.

A single-measure scheme sounds simpler than a full retrofit and is in some ways harder. One measure has to be the right measure, and it has to be safe to install in a property nobody is going to return to — which makes the assessment, and the ventilation judgement that goes with it, the whole job.

Our assessors and coordinators are directly employed rather than subcontracted, and work to an in-house assessment and coordination system built above the PAS 2035 requirements across more than 25 schemes. Coordination runs on our own system with no per-property software fee, so scheme funding stays in the homes rather than in licences.

Ryan
Project Manager

Strategy

Fabric

GBIS typically funds one insulation measure — most often loft or cavity wall insulation, sometimes solid-wall, room-in-roof or underfloor. The assessment establishes which measure the property can actually take, and whether it can safely take one at all. Properties with cavity wall tie failure, existing damp, defective render or a roof in poor condition are not candidates for insulation until those defects are dealt with, and saying so is part of the service.

Service

Insulating a home without checking how it ventilates is the single biggest risk in a single-measure scheme. Ventilation is assessed alongside the insulation measure and provision specified where it is needed, because there is no second visit to put it right.

Renewables

GBIS funds insulation rather than generation, so renewables do not normally form part of the measure mix. Where a household is considering solar PV separately, reducing demand first is still the right order, and the assessment provides the baseline for that decision.

Vital Statistics

Properties in scope: 428 properties. Crawford & Co scope: Retrofit Assessment, Retrofit Coordination. Measures installed: External wall insulation, loft insulation, low-energy lighting. Each assessment records the property’s construction, its existing performance and the modelled improvement from the proposed measure — space-heating demand in kWh/m² per year, carbon in kg per year and estimated energy cost. Eligibility, tenure and Council Tax band are evidenced alongside the technical assessment.

Detailing

The paperwork is what the scheme is audited on, so eligibility evidence and the technical assessment are assembled together rather than separately. Our retrofit condition report was developed in house and approved by both the scheme provider and TrustMark. The work behind it contributed to our managing director’s appointment to the BS 40104 steering group — the British Standard for retrofit assessment. Where PAS 2035 leaves a technical question genuinely open, we take it up with the standard’s authors rather than guess.

Further Data

Standards

PAS 2035 / PAS 2030

Comfort

A single well-chosen measure in a poorly insulated home is a noticeable difference — warmer rooms, less heat lost overnight, a lower bill. A badly chosen one causes damp. That is why the assessment matters more in a single-measure scheme, not less.

Monitoring

Coordinators quality-check each assessment before installation, and post-completion documentation is prepared for TrustMark lodgement through secure data sharing.

Social Value

Naomi, Crawford & Co SurveyorsNaomiSocial value leadDuring this project Naomi was on a Building Surveying degree, funded directly from this contract.

Read about the apprentices, placements and interns we have supported

Contact CC-LTD on Whatsapp
Contact CC-LTD on Whatsapp TT