Retrofit Navigator.

UK households on low incomes can have insulation, heating and heat pumps installed at little or no cost through government-backed schemes. The two that matter most to installers are ECO4 (the Energy Company Obligation, funded by energy suppliers) and Warm Homes: Local Grant (WHLG), run through local councils. Councils can also widen eligibility through LA Flex — for example, households on a low income without benefits, or with a qualifying health condition.

For a retrofit installer, every lead starts with the same question: does this household qualify, and for which scheme? The answer depends on the property's EPC band, the household's benefits or income, the property type, and which council the home sits in — and each council runs its own version of the rules.

Installers typically check eligibility by hand: a spreadsheet of criteria, a scheme PDF, a phone call to the council about local flexibility. Every household is checked from scratch, rules change without notice, and the evidence for a decision lives in someone's inbox. Mistakes surface weeks later as rejected applications.

The brief was to design a platform that turns eligibility into a repeatable, auditable check — one place where an installer's team captures a household, sees instantly which schemes it qualifies for and why, and moves straight into the application.

We started from the rules, not the screens. Every ECO4 and WHLG criterion became a structured, versioned rule — EPC rating, household income, qualifying benefit, property type — with a global rule set maintained by the platform and council overrides for LA Flex routes. An eligibility result is therefore always explainable: each criterion shows as met or not met, with the value that decided it.

We then designed the product for three roles and two plans, and built the flows end to end: installers checking households, installer admins running a team, and a platform admin maintaining councils and rules. An MVP / Full switch shows exactly which features sit in each scope, which made the build estimate easy to discuss.

Installer workspace

• Dashboard — eligibility checks, submitted applications, approval rate and grant value secured, with a six-month trend.
• Customers — every household with its council, EPC band, benefit, income and a 13-stage pipeline from New lead to Funded / closed; search by name or postcode and filter by status.
• Add customer — the council is detected automatically from the postcode, so the right local rules apply from the first check.
• Eligibility check — ECO4 and WHLG evaluated side by side against the current council and global rules, each criterion explained, with a one-click re-run when details change.
• Applications — apply for a scheme straight from the result and track each submission through review to approval.

Platform administration

• Councils & rules — each participating council with its schemes (ECO4, WHLG, LA Flex), a global rule set and council-level overrides for LA Flex income, health-condition and referral routes.
• Rule builder — add, edit and remove rules through a form rather than code; every change is versioned, with a readable history of what changed and when.
• Installers and users — the organisations on the platform, their teams and roles.

Scoped for delivery

An MVP / Full plan switch runs through the whole product: in the MVP, features such as council rule management, reporting and document storage show what the upgrade adds instead of opening. The same split drives a phased build estimate, so the client sees what launches first and what follows.

The result is a working model of the whole product — three roles, the complete eligibility logic for ECO4, WHLG and LA Flex, and the application pipeline — together with a phased MVP and full-scope estimate. It lets a retrofit business or a scheme operator run the workflow with its own team from day one. Client names and figures in the screenshots have been changed.

The same approach — rules as versioned data, explainable decisions, discovery before the first sprint — carries over to any grant, benefit or funding eligibility product. See how we run the first step on our discovery phase page, or how we take a product to launch as an MVP.