BREEAM HEA04 Thermal Comfort
Walker Energy Analysis carries out the thermal comfort modelling needed for BREEAM’s HEA04 credit, using dynamic thermal modelling in IES Virtual Environment. HEA04 is assessed across three components: thermal modelling itself, adaptability to a projected future climate, and thermal zoning and controls, and each one draws on the same underlying model rather than being a separate exercise.
The Three Parts of HEA04
Thermal modelling assesses current-day comfort, and which methodology applies depends on how the building is cooled and used. Mechanically cooled spaces are assessed using PMV and PPD, predicted mean vote and predicted percentage dissatisfied, standard indices for quantifying how comfortable occupants are likely to feel across a range of conditions. Naturally ventilated or free-running non-domestic spaces are instead assessed using the adaptive comfort approach from CIBSE TM52, and residential elements within a scheme are assessed using CIBSE TM59, each allowing more tolerance for indoor conditions since occupants in these buildings can adapt their behaviour, opening windows, adjusting clothing, in a way that air-conditioned occupants generally can’t.
Adaptability for a projected climate change scenario repeats the same assessment using future weather data, to demonstrate the building still performs, or can be adapted to perform, under a warmer climate. Where the criteria aren’t met under future conditions, we set out how the building has been designed, or could be adapted, to meet them later using passive measures rather than requiring the design to pass on day one.
Thermal zoning and controls assesses whether occupants have appropriate control over their own thermal environment, room by room, rather than a single building-wide setting that ignores how different spaces are actually used.
- Dynamic thermal modelling in IES VE, using the appropriate methodology for the building’s cooling strategy and use
- PMV and PPD assessment for mechanically cooled spaces
- CIBSE TM52 adaptive comfort assessment for non-domestic naturally ventilated and free-running spaces
- CIBSE TM59 assessment for residential elements within a scheme
- Future climate scenario testing, with adaptation strategy where current-day criteria aren’t met
- Thermal zoning and controls review, reported for your BREEAM assessor
Where This Overlaps With Other Work
The thermal model behind HEA04 is often the same model used for a TM52 or TM59 overheating assessment, and the passive design element of ENE04 depends directly on it. If any of that work is already happening on your project, tell us early, we can extend the existing model to support HEA04 rather than starting again.
Why Work With Us
We’re a specialist energy consultancy. This is the core of what we do, not a sideline. Every assessment runs through IES VE as standard, we turn changes around quickly, and results come back in a format your team and BREEAM assessor can use immediately.
FAQs
Q: Which methodology applies to my building?
A: It depends on the cooling strategy and use. Mechanically cooled buildings are assessed using PMV and PPD indices. Naturally ventilated or free-running non-domestic buildings use the adaptive comfort approach from CIBSE TM52, and residential elements are assessed using CIBSE TM59.
Q: What happens if the building doesn’t meet the criteria under future climate conditions?
A: We identify what’s driving the risk and set out how the design has been adapted, or could be adapted in future using passive measures, to meet the requirements later, rather than requiring the design to pass outright now.
Q: Is this the same modelling as a TM52 or TM59 overheating assessment?
A: Often, yes, or closely related. Where that modelling already exists for Part O or a standalone overheating assessment, we extend it to cover HEA04 rather than duplicating the work.
Q: Does every space in the building need to meet the same criteria?
A: No, HEA04 excludes ancillary spaces like circulation areas, storerooms and plant rooms. Assessment focuses on the occupied spaces relevant to the credit.
Get Your HEA04 Credit Secured
Talk to Walker Energy Analysis early, and get your thermal comfort modelling working across HEA04 and any related overheating or ENE04 requirements.
Does your project need something else?