Making indoor air quality a design responsibility
Indoor air quality is often considered late in a construction programme, when the finishes are installed, handover is approaching and someone needs to arrange testing. By then, many of the decisions that determine the results have already been made.
BREEAM UK New Construction V7.1 gives project teams further reason to address air quality earlier. Its Hea 04 requirements connect the indoor air quality plan, ventilation design, material selection and post-construction testing. The practical value comes from managing those activities together.
For fully fitted assessments, Hea 04 offers five standard credits and up to two additional exemplary credits. The indoor air quality plan is worth one credit and forms a minimum standard for ratings of Very Good and above. That recognition was introduced with Version 7. The V7.1 changes develop the requirements further, particularly around professional competence, ventilation pathways and testing arrangements.
A plan should influence what gets built
V7.1 requires the indoor air quality plan to be prepared by a suitable IAQ professional, defined as someone with at least three years’ experience in IAQ monitoring. The same competence requirement applies to post-construction measurements.
This places greater emphasis on practical experience. An effective plan needs to anticipate how pollutants could enter or accumulate within the completed building, and how construction activities, material choices and ventilation arrangements could affect the outcome.
The evidence requirements also matter. At completion, the project team must demonstrate how the plan influenced design, specification and installation, within the scope of the credits being pursued. A generic document issued at the start of a project will have limited value if nobody takes responsibility for implementing it.
Air intake locations need a defensible basis
One significant V7.1 change is the removal of the simple 10 m separation option from the ventilation-pathway methodology.
The remaining routes reference recognised design guidance and allow pollutant dispersion modelling to inform intake and exhaust locations. This does not make modelling compulsory for every building. It does mean that a distance on a drawing should be supported by an appropriate assessment of the ventilation arrangement and surrounding pollution sources.
That is particularly relevant on constrained urban sites. Roads, delivery areas, car parks and neighbouring exhausts can influence the air reaching an intake. Their effects depend on source characteristics, building geometry and airflow, as well as separation distance.
Filtration needs the same attention. The criteria specify a supply-air classification of at least SUP 2, with filtration selected according to outdoor air quality. The methodology also calls for consideration of appropriate gas-phase filtration where significant gaseous pollution is identified. A particulate filter cannot be assumed to address nitrogen dioxide or other gaseous pollutants.
Low emission products still need verification
Construction-product emissions remain a substantial part of Hea 04, with two standard credits and up to two exemplary credits available. V7.1 also updates aspects of the paint, coating and wood-product requirements, so specifications and evidence schedules should be checked against the applicable manual.
Product compliance and completed-building performance answer different questions. Emission certificates describe products under specified test conditions. Room concentrations reflect the combined materials installed, their quantities, the space available and the ventilation provided.
A building can therefore contain compliant products and still experience elevated indoor concentrations. Substitutions, late decoration and changes to ventilation arrangements can all affect the result. Material evidence should follow the products actually installed.
Testing flexibility needs careful use
V7.1 allows measurements to be completed within the first two weeks of occupancy where pre-occupation testing is prevented by programme constraints. Pre-occupation testing remains the preferred arrangement.
This flexibility may help project delivery, but sampling still needs representative conditions and a justified strategy. Testing after occupation also introduces potential contributions from furniture, cleaning and occupant activities, which need to be considered when interpreting results.
The formaldehyde and TVOC criteria remain important checks on the completed building. They do not provide a comprehensive assessment of every aspect of indoor air quality or a guarantee of performance throughout occupation.
The practical opportunity is to use Hea 04 to establish a clear chain of responsibility: assess external sources, inform ventilation design, control material selection, manage installation and verify the completed spaces. Testing then becomes the final check on a process that has been managed throughout the project.
That approach gives the credits a useful purpose. It also gives building owners a stronger basis for maintaining indoor air quality after handover.
Sources
BRE Global Ltd. BREEAM UK New Construction Version 7.1.0, SD6074, issued 26 August 2026. Hea 04 Indoor air quality. Read the Hea 04 technical manual
BRE. Summary of changes BREEAM New Construction V7.1, PN748-1.0. Hea 04 Indoor air quality, page 9
