Two packages, one school, still open
Two linked heating packages delivered consecutively with optional overlap. The main school strips out two gas boilers and installs two 18 kW high-temperature heat pumps on the retained low-loss header, heating only. The annex strips a combi and installs a 5 kW heat pump with a 170 litre unvented cylinder for heating and hot water. The school stays open throughout.
- Client
- Oakridge Primary School
- Site
- Lavender Lane, Nottinghamshire · NG12 5BX
- Work type
- Mechanical and electrical, heat pumps
- Reference
- BAI-RAMS-OPS-DCB-001
- Sector
- Education
- Status
- Draft for review
Illustrative example: fictional project and parties.
Two packages, linked but distinct
Two installation streams run with different system arrangements and different complexity. The main school is the critical path because it carries the electrical-load-monitoring hold point and the retained low-loss header integration. The annex follows, or partly overlaps where labour and supervision allow.
The main school supply strategy must be confirmed by formal load monitoring and validation before final energisation design is signed off. This is hold point HP-01, the single critical-path dependency. No energisation, commissioning or handover until it closes.
Five stages, eight hold points
Pre-construction first, then main school strip-out and install, then the annex. Final commissioning and handover close out both packages together. Eight mandatory gates run the sequence; HP-01 sits at the front, not the back.
| Hold point | Signed off by |
|---|---|
| HP-01 Electrical load monitoring, before energisation design | NICEIC and BuiltAI |
| HP-02 Area release before works in each zone | School and BuiltAI |
| HP-03 Safe isolation proven before any strip-out | BuiltAI supervisor |
| HP-04 Gas capped at appliance points | Gas Safe engineer |
| HP-05 Pressure testing before fill or commissioning | BuiltAI supervisor |
| HP-06 Electrical inspection and certification | NICEIC electrician |
| HP-07 Unvented cylinder safety, discharge and G3 checks | G3-qualified installer |
| HP-08 Final commissioning across both packages | BuiltAI and client |
Both packages follow the same discipline: isolate, strip out, install, connect, test, commission, handover. The detail differs; the discipline does not.
RAG-rated, four by four
Severity from 1 to 4 times likelihood from 1 to 4, banded into green, amber and red. Controls are applied to drive every initial-rated risk into the green band before work begins.
Seven activities carry stricter control than the standard regime: load monitoring, gas isolation and capping, boiler strip-out, heat-pump lifting, retained header integration, unvented cylinder safety and the live-school overlay. Each carries a named hold point or a competent-person requirement.
Three registers, forty-two hazards
General project risks plus task-specific registers for each package: general 7, main school 21, annex 14. Initial scores reach red across many activities; controls drive every residual into the green band before work commences.
| Hazard | Initial | Key controls | Residual |
|---|---|---|---|
| Unsafe energisation from incorrect assumptions | 12 Red | Formal load monitoring, validation hold point HP-01 before energisation design | 4 Green |
| Working in a live school environment | 12 Red | Segregated zones, agreed access, no unattended tools in pupil areas | 4 Green |
| Lifting and positioning the 18 kW heat pumps | 12 Red | Mechanical aids, planned lift route, exclusion zone, competent operatives | 4 Green |
| Hidden service strike during penetrations | 12 Red | Check drawings, inspect both sides, controlled and supervised drilling | 4 Green |
| Unvented hot water safety risk | 12 Red | Install to manufacturer and unvented requirements, verify safety kit and discharge, HP-07 | 4 Green |
| Gas hazard during boiler isolation | 12 Red | Competent operative, isolate before dismantling, cap at appliance point | 4 Green |
Residual position: zero red, zero amber, all hazards reduced to the green band once controls are in place.