A school plant room can be replaced in the summer holidays if everything except the physical work is finished before the school closes. The survey, asbestos information, funding, design and orders belong in the months before; the holiday is for strip-out, installation, cleansing and commissioning, with the heating back in service before the building is occupied again.
This guide sets out that timeline step by step, using plant room and heating projects ComGas has delivered for schools in Surrey and London.
How long the work takes on site
The scope sets the programme. A plant room replacement on its own can be short. Work that reaches beyond the plant room takes longer.
- Three weeks: at Send CofE Junior School, Woking, the main plant room was replaced within a three-week programme: gas service alterations, new condensing boilers, a new flue and new controls, both designed by ComGas, and weatherproofing of the flat roof around the flue.
- Six weeks: at Our Lady of The Rosary School, Staines, the wider rebuild also renewed the plant room’s air supply and electrical distribution and removed the old feed and expansion tank.
- Two months: at St James Primary School, Elstead, a biomass installation was removed and replaced with gas-fired condensing boilers. Most of the extra time went on the strip-out.
- Twelve weeks: at Lowther Primary School, Barnes, an air source heat pump replaced the gas boiler installation, with new heating distribution, a new building management system and upgraded incoming electrical supplies.
Work that cannot fit inside a holiday can often be phased. At Loseley Fields Primary School, Godalming, a six-week heating distribution refurbishment was phased across classrooms, corridors and plant areas so teaching could continue.
The planning timeline
1. Survey the plant room
Survey what is there now: boilers, flue, gas service, pumps, controls, pipework and the route for getting old plant out and new plant in. The design, price and programme all start here.
2. Deal with asbestos early
HSE says that if a building was built or refurbished before 2000, you should assume it contains asbestos. Before refurbishment, a refurbishment survey must locate and identify asbestos-containing materials, including those hidden in the building fabric, before work begins on the premises or on equipment. The area must be vacated during that survey, and any removal that is required happens before the work starts. Ask the school’s duty holder for the asbestos register and management plan, and allow time for the survey and any removal well before the holiday.
3. Confirm the funding
Funding fixes the date. Eligible academies, sixth form colleges and voluntary aided schools can apply to the Condition Improvement Fund in an annual bidding round. Other schools should check the route with their local authority or trust. Confirm the funding before orders are placed, so the programme does not depend on a decision that comes too late.
4. Design the system, not just the boilers
New boilers need a flue and controls that suit them. Condensing boilers run at lower flue-gas temperatures and produce condensate, so a flue that served older non-condensing boilers is rarely suitable to keep. At Send, ComGas designed the new flue and the control strategy alongside the boiler replacement, so the plant was commissioned as one system. At Our Lady of The Rosary, the design also covered the room’s air supply and its electrical distribution board.
5. Order early and check lead times
Confirm lead times for boilers, flue components, pumps and controls before fixing the start date, and have the plant on site, or confirmed for delivery, before the school closes. A three-week programme has no room for a late delivery.
6. Strip-out
The old plant is isolated and removed first. The strip-out can be bigger than it looks: at Our Lady of The Rosary it included the redundant feed and expansion tank, and at St James it was the main part of a two-month programme.
7. Installation
The gas service is altered, then the boilers, flue, plant room equipment, controls and electrical supplies go in. Builders work and roof making good around a new flue belong in the same programme; at Send, ComGas weatherproofed the roof around the new flue within the mechanical package.
8. Cleansing
The system is cleansed before it is commissioned. At Send, Our Lady of The Rosary and St James, pre-commission cleansing was part of the scope, and at Loseley Fields the system was flushed and water treated before handover.
9. Testing and commissioning
New or altered gas pipework is tightness tested and purged before the appliances are lit; our guide to gas tightness testing and purging explains the order. After work on a gas appliance, regulation 26(9) of the Gas Safety (Installation and Use) Regulations 1998 requires the engineer to examine the effectiveness of the flue, the supply of combustion air, the operating pressure or heat input, and the appliance’s operation to ensure it functions safely.
10. Handover
At handover the school should receive written records. ComGas issues a CP15 record for the new boilers and a CP16 record for the testing and purging of the gas pipework, with record documentation for the school to keep with its building records. Our page on commercial gas safety certificates explains each record.
11. The first heating season
The first weeks after the school reopens are the first time the new plant runs under a full building load. Plan a check of the controls and room temperatures once the heating is in regular use, and add the new plant to a planned preventative maintenance programme. Our guide to how often commercial boilers should be serviced covers the servicing interval.
Working in a school
All our engineers and staff who attend schools hold enhanced DBS checks. Dates in a school are fixed by the term, so finishing on time, or early, matters. At St Pauls Catholic Primary School, Thames Ditton, ComGas carried out the mechanical and electrical enabling and reinstatement works for RAAC remediation and finished two weeks ahead of programme, so the school could return staff and pupils to their classrooms early.
Key facts
- Survey, asbestos information, funding, design and orders should be complete before the holiday starts.
- A plant-room-only replacement can be short: Send CofE Junior School’s was programmed into three weeks.
- Wider scope takes longer: six weeks at Our Lady of The Rosary, two months at St James, twelve weeks at Lowther.
- HSE says to assume asbestos is present in buildings built or refurbished before 2000; a refurbishment survey must come before the work.
- At handover, ask for the CP15 and CP16 records and keep them with your building records.
Frequently asked questions
Can a school plant room really be replaced in three weeks?
Where the work is confined to the plant room, yes. At Send CofE Junior School the strip-out, gas service alterations, installation, cleansing and commissioning were planned as one continuous three-week operation.
What if the work will not fit in the holiday?
Phase it. Heating distribution work can often be carried out area by area while the school is open, as it was at Loseley Fields. The plant room changeover itself is best kept to a period when the heating is not needed.
What records should we get at the end?
A CP15 record for the boilers, a CP16 record for the gas testing and purging, and record documentation for the installation. Keep them with your building records.
Planning a plant room replacement?
ComGas plans and delivers plant room replacements and commercial boiler replacement for schools across Surrey and the surrounding counties, as part of our wider mechanical services. See our work in education, or call 01252 214120.