The verdict in three sentences
For a London firm of 8 energy assessors carrying out 4,000 jobs a year, a tablet app for site surveys and reports costs, as a 2026 order of magnitude, GBP 22,000 to 38,000 and ships in 4 to 5 months. It removes evening re-keying, produces reports on the same day and lets each assessor fit in 1 to 2 extra jobs a week. The non-negotiable point: the app does not replace the approved EPC software, it connects to it and feeds it clean survey data.
What the app does and what it leaves to the approved software
EPCs must be produced with approved RdSAP software, now on RdSAP 10, and lodged on the government register through an accreditation scheme. The classic mistake would be to try to rebuild everything. The custom app handles everything around the calculation: booking, on-site surveys, photos, the other inspections and delivery to the client.
| Module | Core version | Full version |
|---|---|---|
| Online booking for estate agents and solicitors | GBP 2,500 | GBP 4,500 |
| Assessor scheduling and route optimization | GBP 3,000 | GBP 5,500 |
| Offline tablet survey (rooms, dimensions, heating, glazing) | GBP 5,500 | GBP 8,500 |
| Geotagged photos and defect annotations | GBP 2,000 | GBP 3,500 |
| Report templates for EICR, gas safety, floor plans | GBP 3,500 | GBP 6,500 |
| Connector to the approved RdSAP software (survey import and export) | GBP 2,500 | GBP 5,000 |
| Client portal and invoicing | GBP 2,000 | GBP 3,000 |
| Field testing and go-live | GBP 1,000 | GBP 1,500 |
| Total | GBP 22,000 | GBP 38,000 |
How feasible the connector is depends on the EPC software vendor: some offer an XML import or an API, others only a file import. Check this before signing, as it is the item that varies most.
Where the time goes today, and what changes
An assessor completes 2 to 3 jobs a day on average. The time lost is not on site but before and after the visit.
| Task per job | Paper or spreadsheet workflow | With the app | Gain |
|---|---|---|---|
| Preparing and confirming the appointment | 10 min | 2 min, automatic SMS reminder | 8 min |
| On-site survey | 45 min | 40 min, guided checklists | 5 min |
| Evening re-keying of survey data | 25 min | 0 min, synchronization | 25 min |
| Sorting and inserting photos | 15 min | 2 min, automatic attachment | 13 min |
| Formatting and sending the report | 20 min | 5 min | 15 min |
| Total excluding EPC calculation | 115 min | 49 min | 66 min per job |
With 66 minutes saved per job and about ten jobs a week, each assessor frees around 11 hours a week. Part of it ends the evening re-keying sessions, the rest fits in 1 to 2 extra jobs.
Trade-specific requirements
Several constraints must appear in the specification:
- Full offline mode: basements, underground car parks and old buildings often have no signal.
- Audit trail: timestamped survey data and photos, kept for years for accreditation scheme quality audits and disputes.
- Assessor accreditation: the app blocks assigning a job to an assessor whose accreditation has lapsed.
- Insurance and complaints: one-click export of a complete file speeds up the response to a complaint.
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Tom, managing director of an energy assessment firm in London (fictional illustrative case), employs 8 assessors and charges an average of GBP 110 per job across EPCs and related inspections. He invests GBP 32,000 in the app, plus GBP 3,500 a year for maintenance and hosting.
Assuming a cautious one extra job a week per assessor over 44 working weeks, the firm completes 352 more jobs a year, i.e. GBP 38,720 of additional revenue. With a 50 % margin on these jobs, the gain reaches about GBP 19,400 a year, plus the re-keying hours removed. The project pays back in about 2 years on extra jobs alone, faster if assessors fit in two extra jobs a week.
FAQ
Can the app calculate the EPC itself?
No, the EPC must be produced with approved RdSAP software and lodged through an accreditation scheme. The app prepares the survey data and sends it to the approved software, saving about 25 minutes of re-keying per job on average.
How long does the project take?
Allow 4 to 5 months as a 2026 order of magnitude: 3 weeks of scoping with two assessors, 10 to 12 weeks of development and 3 to 4 weeks of testing on real jobs.
Which tablets are needed?
A mid-range Android tablet or iPad, GBP 300 to 600 per assessor, is enough. A rugged case and a power bank help for days of 3 jobs without recharging.
Can estate agents book directly?
Yes, a portal lets agents and solicitors pick a slot, upload documents and download reports. Firms that open one often see 30 to 50 % fewer booking phone calls.
What happens if the EPC software vendor changes its format?
The connector should be covered by the maintenance contract, GBP 2,500 to 5,000 a year as a 2026 order of magnitude. A format change usually takes 2 to 5 days of work.
Let's scope your project. Tell us how many assessors you have, your job volumes and your EPC software: we will price the scope, an indicative budget and a field rollout schedule. Detailed quote within 48 h. WhatsApp +221 77 596 93 33.
Mohamed Bah
Fondateur, Kolonell
Passionate about digital and entrepreneurship in Africa, Mohamed has been helping Sénégalese businesses with their digital transformation since 2020. Founder of Kolonell, he believes every SME deserves a professional and accessible online présence.
