INDUSTRY COMMENT


powered anemometer, with intermittent extract fans remaining an exception where a vane anemometer can still be used. For new properties, airflow test and commissioning results are expected to be provided to Building Control within five days of the final test. Testing requirements may also apply to certain new systems in existing properties, including new c-MEV systems, major changes to these systems and some mechanical ventilation fans with longer or more complex ductwork.


It will not be enough to simply say a system has been installed. Contractors and housing providers will need records showing that the system has been commissioned correctly, that airflow has been measured properly and that results have been passed on to the relevant authority.


The equipment point is also important. Powered anemometers are significantly more expensive than the kit some smaller contractors may currently use, so this could have cost and training implications. The evidence trail needs to be built into the project from the start.”


• Energy performance changes will raise the stakes for ventilation products


The Building Regulation changes also sit alongside wider energy and carbon performance requirements, including low- carbon heating, on-site renewable electricity generation and new energy assessment methodologies such as SAP 10.3 and the Home Energy Model.


EQMAX_"Now in stock"_BSEE_half horizontal_175x260_1.qxp 03/08/2026 11:58 Page 1


For ventilation, one of the key technical changes is the tightening of Specific Fan Power requirements. Continuous MEV will move to 0.5W/(l.s) for new builds and 0.7W/(l.s) for existing builds, while continuous d-MEV will have a standalone value of 0.3W/(l.s). MVHR will


move to 1.4W/(l.s) for new builds and 1.5W/(l.s) for existing builds.


Specific Fan Power is essentially the


relationship between fan power and airflow. The lower the number, the more efficient the fan is at moving air.


Some of the limits are becoming harder to meet, which will affect manufacturers, consultants and specifiers. Products that do not meet the new requirements could fall away from specification routes, so product choice and performance data will need to be checked carefully. The wider direction is towards more airtight,


more energy-efficient homes. That is positive, but it also means ventilation cannot be under- specified or value engineered out without increasing risk elsewhere.”


• Handover, maintenance and resident understanding are becoming part of the picture


The final area housing providers and developers should not overlook is handover. Where building work takes place, information about ventilation, fuel and power, overheating and on-site electricity generation should be provided to the owner in an appropriate format. The updated guidance also includes expectations around fan checks, inspections, maintenance, commissioning and summer bypass testing for MVHR systems. A ventilation system is only effective if it is installed properly, commissioned properly and understood by the people responsible for it afterwards.


For social housing providers, this is particularly important because the resident may not have been involved in the specification or installation process. Good handover should explain what has been installed, how it should be used, what


For organisations


commissioning new homes, major refurbishments, system upgrades or higher- risk building work, the updated standards could have a significant impact on project planning, contractor selection, design coordination and compliance records.


maintenance is required and what evidence has been provided. The regulations are not just changing what systems need to achieve on paper. They are changing how ventilation is designed, evidenced, installed and handed over. That is why competence, early planning and proper documentation will matter more than ever. envirovent designs, manufactures, installs and commissions ventilation systems for new build, social housing, residential and commercial projects. The company also offers NICEIC- approved domestic ventilation training for installers looking to build competence ahead of the 2027 changes.


AVAILABLE TO ORDER NOW


YOUR NEW IDEAL WATER HEATER IS NOW IN STOCK


10 MODELS Hot Water from the UK’s


commercial heating market-leaders.


To view our full range of products visit:


idealcommercialheating.com/hot-water Read the latest at: www.bsee.co.uk Ideal EQMAX hp BSEE Oct26.indd 1 9/9/26 13:08 BUILDING SERVICES & ENVIRONMENTAL ENGINEER OCTOBER 2026 27


OUTPUTS: 20kW to 120kW


STORAGE::: 210 to


538 litres *Terms & conditions apply


Designed for replacement


& refurbishment projects.


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38