Two linked work packages delivered consecutively with optional overlap: Main School — strip out two existing gas boilers and install 2 × 18 kW high-temperature ASHPs feeding the retained low-loss header on a heating-only basis, with existing DHW retained; and Annex / Nursery — strip out the combi and install 1 × 5 kW ASHP plus 170 L unvented cylinder for heating and DHW. The school stays open throughout.
Two packages. One school, still open. The Main School is the critical path because it carries the electrical-load-monitoring hold point and the retained-LLH integration. The Annex follows — or partly overlaps where labour and supervision allow.
Combined Method Statement and RAG-rated Risk Assessment, prepared by Built AI for the two-package decarbonisation heating upgrade at Oakridge Primary School. Issued in draft for consultant and client review prior to mobilisation.
Two parallel installation streams with different system arrangements and different complexity profiles. The Main School is the critical path; the Annex follows or partly overlaps where labour and supervision allow.
Boiler plant replacement, retained LLH, heating-only.
Combi replacement, ASHP + unvented cylinder, heating + DHW.
External ASHP plant on dedicated pads, primary pipe route into the Main School plantroom, and a separate compact arrangement at the Annex / Nursery. The school operates throughout — segregation, deliveries and noisy works coordinated with Estates.
Most hold points in this RAMS gate a single phase. One gates the whole project — and it sits at the front of the programme, not the back.
The Main School supply strategy must be confirmed by formal load monitoring and validation before final energisation design is signed off. This is the single critical-path dependency for Package 01. No final energisation, no commissioning, no handover until this hold point is closed.
Pre-construction first, then Main School strip-out and install, then the Annex. Final commissioning and handover close out both packages together.
Survey confirmation, RAMS approval, access agreement, electrical load monitoring, plant location confirmation.
Isolate gas, electrical and heating. Drain. Remove two boilers and redundant flues. Cap gas at appliance points.
External ASHP supports and units. Primary pipework ~25m × 2. LLH tie-in. Electrical first-fix and second-fix.
Combi removal. Cap gas. External 5kW ASHP. 170L unvented cylinder with safety kit. Heating + DHW services.
Both packages tested, certified, handed over. O&M issued. Estates and operator training delivered.
Both packages follow Isolate → Strip-out → Install → Connect → Test → Commission → Handover. The detail differs but the discipline is identical.
Procurement and practical delivery references for both packages. Final confirmations sit against six dependencies that must be closed before mobilisation.
2 × 18 kW high-temperature ASHPs · External support arrangement (plinths, AVMs) · Primary pipework (~25 m × 2) · Mechanical tie-in to retained LLH · Electrical supplies, isolators, controls.
1 × 5 kW ASHP (external) · 170 L unvented cylinder (internal) · Safety kit (expansion vessel, PRV, tundish, discharge) · Heating + DHW pipework · Local electrical supply.
Primary flow/return pipework · LLH tie-in fittings · Pipe supports + brackets · External UV-protected insulation · Internal lagging · Drains, vents, commissioning points · AVMs · Condensate drainage · Penetration sealing.
Electrical supply, isolators, containment · Controls wiring · Protective devices · Test instruments and certification · Temporary monitoring kit for load validation · Final connection materials.
Lifting aids · Core drilling kit · Pipe fabrication tools · Electrical test equipment · External access platforms · Temporary barriers + signage · Floor protection · Drain hoses + containers.
Final ASHP location confirmation · Pipe route confirmation · LLH tie-in strategy · Main electrical supply post-validation · Annex discharge route · Local electrical connection points.
Mandatory quality control gates. HP-01 (load monitoring) sits at the front of the programme; the rest follow the natural sequence of strip-out, install, test, commission, handover.
Main School supply strategy confirmed by formal load monitoring and validation. No final energisation design until closed.
Each work zone formally released by the school before works commence. Barriers and signage in place.
Gas, electrical and heating isolations proven before any strip-out begins.
Gas safely capped at appliance points before affected areas are left unattended.
All new pipework pressure-tested and recorded before fill or commissioning.
Electrical inspection, testing and certification complete before energisation.
Annex unvented cylinder safety kit, discharge and commissioning checks complete before handover.
Final commissioning complete across both packages before client sign-off.
Schools are the most sensitive live-occupied environment we work in. Pupil safeguarding, access control, deliveries, noise, and term-time / holiday timing all sit on top of standard CDM controls.
Works delivered in an active school. Segregated zones, agreed access, no unattended tools or materials in pupil areas. School operations protected.
Lockable storage. End-of-day security checks. No pupil access to plant, materials, drilling areas, or external ASHP zones during working hours.
Disruptive works (drilling, deliveries, ASHP placement, cutover) prioritised for school holidays where programme allows. Quieter activity acceptable in term time with school agreement.
Planned delivery windows. Banksman during reversing. Exclusion zones at offload. Out-of-hours delivery route used where pupil drop-off / collection coincides.
Time noisy works carefully — avoid morning registration, lunch and home-time. Dust sheets, local extraction, RPE for cutting. Communicate disruptive activity in advance.
Fire extinguishers in plantroom and at hot-work zones. Permit for hot works if required. Daily end-of-shift fire check. School muster point known to all operatives.
Seven steps for the Main School, four for the Annex. Each procedure has an objective, numbered method and gating note. Hold points are referenced inline so progression discipline is unambiguous.
Area release is HP-02 — formal sign-off required.
Safe isolation is HP-03 — no strip-out until closed.
Gas capping (HP-04) closes before area is left unattended.
Lifting plan in place before any boiler arrives on site.
No insulation closure before pressure test passes (HP-05).
HP-01 + HP-06 both required before any energisation.
Commissioning sign-off feeds HP-08 (final acceptance).
Same isolation discipline as Main School — no shortcuts because package is smaller.
Condensate route verified before commissioning.
G3 compliance is HP-07 — discharge and safety controls verified.
All four hold points must close before handover.
Severity (1–4) × Likelihood (1–4). Score banded into Green / Amber / Red. Controls applied to drive every initial-rated risk to ALARP and into the Green band before work begins.
Low risk — acceptable with standard controls.
Score 1–4Medium risk — active management and supervision required.
Score 5–8High risk — strict controls, permits, competent supervision and review.
Score 9–16General project risks plus task-specific registers for each package. Initial scores reach Red across many activities; controls drive every residual into the Green band before work commences.
0
None remaining once controls are in place.
0
None remaining once controls are in place.
All
All residual risks reduced to Green / low-risk working level.
Activities where the consequence of failure justifies stricter control than the standard supervisory regime. Each one carries a named hold point or a competent-person requirement.
Critical-path dependency. HP-01 must close before final energisation design. Competent NICEIC engineer only.
Each package starts with gas isolation; ends with gas capped at appliance points. Gas Safe operative for any modification or recommissioning.
Two existing boilers (Main School) plus one combi (Annex). Manual handling and exposed-services exposure during removal.
Mechanical aids for the 18 kW units; controlled lift for the 5 kW. Exclusion zones throughout.
Hydraulic interface of the new system. Tie-in points confirmed before cutting; staged installation.
G3-qualified installer. Full safety kit, discharge route verification, commissioning of all safety controls.
Pupil safeguarding, segregated routes, term-time vs holiday programming, deliveries co-ordinated with school.
Minimum PPE for the works plus the supplementary safety equipment held on site. Emergency arrangements confirmed at induction and reviewed if site conditions change.
No operative starts work without attending the briefing, agreeing the safe system of work and signing this record. This document is currently in draft status — final approval signatures from the consultant and client follow review.
This RAMS briefing was delivered in full and all operatives confirmed understanding of the content.
Oakridge Primary School representative — area release and area-by-area sign-off.