2020 and 2050 weather files

The weather files with reference to the 2020s will cover the 30 year climatic period around that decade, i.e. 2010 to 2040, with the 2020s being the middle of the three decades (10’s/20’s/30’s).  Therefore any projects that will be completed before 2025 should use the 2020 weather files for mechanical ventilation and the 2050 weather files for natural ventilation.