Why thermal comfort matters in education
Comfort and air quality are inseparable. A classroom can have well-ventilated, clean air and still be uncomfortable to learn in if it is too warm, too cold, too humid or too dry. Conversely, comfort interventions that ignore ventilation often make air quality worse — sealing rooms, reducing window opening, or compensating with cooling that limits fresh-air supply.
In schools the stakes are practical: drowsy children in over-warm afternoons, draughty rooms in winter, condensation on cold walls in spring, and staff complaints in upper-floor classrooms in summer. Treating thermal comfort as a proper engineering and operational question — not a perception problem — is what allows real progress.
The parameters that shape comfort
Thermal comfort in classrooms is influenced by a small set of parameters, all of which respond to the way the building is operated as well as how it was designed.
- Air temperature — the headline metric, but rarely the whole story
- Relative humidity — affects perceived warmth, dryness and mould risk
- Radiant temperature — surfaces, glazing and solar gain matter as much as air
- Air movement — gentle movement helps in summer, draughts cause complaints in winter
- Occupant activity and clothing — younger children, PE warm-ups and SEND needs all shift baselines
- Operation — when heating, cooling and ventilation actually run versus when they are needed
Overheating in school buildings
Overheating has become a defining school-comfort issue. Better-insulated buildings, larger glazed areas, denser occupancy and warming summers combine to push more classrooms above accepted comfort thresholds for longer periods.
Assessment usually follows CIBSE TM52 (non-residential overheating) or TM59 methodology where applicable, benchmarked against BB101 criteria for new and refurbished schools. The output is a clear picture of which rooms exceed limits, when, by how much, and what the most effective interventions are.
Improving comfort in practice
Improvement programmes typically combine operational measures, fabric and shading upgrades, and ventilation strategy changes. Active cooling is usually a last resort because of cost, energy use and the way it can defeat ventilation strategies. A structured comfort assessment helps schools choose the right combination for each building.
What we assess and measure
- • Temperature and relative humidity in occupied rooms
- • Solar gain, glazing and shading review
- • Occupancy patterns and room use
- • Heating, cooling and ventilation operation
- • Overheating assessment (CIBSE TM52 / TM59)
- • Benchmarking against BB101 and CIBSE Guide A
Recommendations and outputs
- • Written comfort and overheating report
- • Room-by-room comfort ranking
- • Operational and behavioural quick wins
- • Fabric and shading upgrade recommendations
- • Ventilation strategy adjustments
- • Evidence for capital and decarbonisation cases
Suitable schools and settings
- Upper-floor and south-facing classrooms
- Recently insulated or refurbished school buildings
- School halls and large-volume spaces
- Modular and temporary classrooms
- SEND settings with specific comfort needs
- Net-zero and decarbonisation programmes
- Schools responding to summer overheating complaints
- MATs standardising comfort strategy across sites
Frequently asked questions
What is thermal comfort and why does it matter in schools?+
Thermal comfort is the combination of temperature, humidity, air movement, radiant heat and what occupants are wearing and doing. In schools it directly affects concentration, behaviour, attendance and the comfort of staff. Classrooms that are too warm, too cold, too humid or too dry compromise learning regardless of any other intervention.
What is school overheating?+
Overheating is sustained exposure to temperatures above a recognised comfort threshold during occupied hours. In UK schools it is most common in upper-floor classrooms, south- and west-facing rooms, large-volume halls and recently insulated buildings without compensating shading or ventilation. CIBSE TM52 / TM59 provide the standard overheating assessment methods.
Is there UK guidance on classroom temperatures?+
Yes — Building Bulletin 101 (BB101) sets out summer and winter criteria for new and refurbished schools, including overheating limits. The Workplace (Health, Safety and Welfare) Regulations also apply to staff working temperatures. Comfort criteria are typically benchmarked alongside BB101 using CIBSE Guide A and TM52 / TM59.
How do you assess thermal comfort?+
We measure temperature and relative humidity in occupied rooms over a representative period, review building fabric, glazing and shading, and consider occupancy and use. For overheating-specific work, we follow CIBSE TM52 / TM59 methodology and benchmark against BB101.
Can comfort be improved without air conditioning?+
Often, yes. Improved shading, night purge ventilation, occupancy-aware scheduling, fabric and glazing upgrades, and better use of existing systems can deliver substantial comfort improvements before any cooling solution is considered. Air conditioning is usually a last resort in schools.
Ready to take a closer look at your school's air?
Tell us about your buildings and the rooms or year groups you're concerned about. A specialist will be in touch within one working day.