Retrofit at scale is not sold door to door. It is contracted — through frameworks, obligations and public procurement — and understanding that structure explains where the work in this industry actually sits.

The three routes money reaches a property

  1. Supplier obligation (ECO4). Energy suppliers are legally obliged to deliver a set volume of efficiency measures. They rarely install anything themselves; they contract managing agents, who contract installers, who subcontract assessors. The obligation is the pressure that makes the whole chain move.
  2. Public grant programmes. Central government allocates funding to social landlords and local authorities for decarbonising their stock. That money is spent through procurement, which means frameworks and tenders rather than quotes.
  3. Private and able-to-pay. Smaller, but growing — homeowners commissioning work directly, often starting with an assessment and a plan.

What a framework is, and why it matters

A framework is a pre-approved list of suppliers a public body can call off from without running a fresh tender each time. Getting onto one is slow and paperwork-heavy; being on one means being invited to bid for work that never reaches the open market. This is why large retrofit contractors invest so much in framework applications, and why smaller firms often subcontract to those who are already on them.

What is actually assessed in a bid

  • Accreditation and certification — TrustMark registration, PAS 2030 for installers, PAS 2035 roles evidenced.
  • Insurance at the levels the contract specifies, which are usually higher than a small firm carries by default.
  • Capacity — can you deliver the volume, with named people.
  • Social value — increasingly heavily weighted in public procurement: local employment, training, apprenticeships.
  • Quality and compliance history.

Where assessors fit

Assessors rarely hold the head contract. The realistic route into funded work is subcontracting to a managing agent or a principal contractor who already has it — which means being findable, being accredited, and being able to turn work around at volume without compliance failures. Audit performance matters more than price at that level: a contractor whose assessor gets certificates rejected loses more than they saved.

What this means if you are a homeowner

Mostly that the offer arriving at your door has travelled through several hands, and the incentives at each stage are worth understanding. The assessment should be independent of whoever wants to sell you the measures. That separation is written into PAS 2035 for good reason.

If you are an accredited assessor looking for subcontract work, we are building a nationwide network — see joining our assessor network.