Risk of overheating in the Netherlands (TOjuly) | Airios
top of page

Risk of overheating in the Netherlands (TOjuly)

Background information TOjuly.


A short lesson in history about the introduction of this requirement: The RVO had W/E Advisors investigate the criterion and limit value to limit the risk of overheating in new-build homes. The report 'Limits of summer comfort in new homes in Building Decree' was the result and formed the basis for RVO.nl to include TOjuly in the building regulations.

If a new-build home only complies with BENG 1, 2 and 3, a problem may arise in the summer. The house can become too hot. For this reason, the requirements of TOjuly (TO = Temperature Exceedance) also come into effect.


This means that from that moment on, a new-build home must not only meet the BENG requirements, but also those of TOjuly. An environmental permit is only issued when a home meets both requirements.

The TOjuly has been definitively adopted with an amendment to the Building Decree regulation.


The definitive limit value for the risk of overheating has been clarified and set at 1.20 and applies to new-build homes without active cooling. The limit value is higher than the previously determined limit value of 1.00.


The requirement to limit the risk of overheating in new-build homes will take effect on 1 January 2021.


Overheating illustration

bottom of page