Timescale
The weather files for each decade cover a 30-year climatic period around that decade.
For example, 2020s weather files cover the period 2010 to 2040. 2020s are in the middle of the three decades (10s / 20s / 30s).
2020s and 2050s (NC)
New Construction projects assessed under the relevant standards should continue to use the 2020 weather files for mechanical ventilation, and the 2050 weather files for natural ventilation.
CIBSE weather files are available here: CIBSE Weather Data
2030s (RFO)
Refurbishment projects assessed under the relevant standards should use the Prometheus project, which contains 2030s weather files.
These can be found here: Prometheus weather data
18-Dec-2024 - Merged with KBCN000006. Prometheus link updated. Title updated. 04-Jul-2024 - Clarified that 2020 and 2050 weather files are still valid for the applicable standards and guidance applied to all relevant UK standards. Applicability to international standards removed and link to CIBSE weather data added.
