temperatures described below then the Contractor or a heating expert should be asked to consider if the building is overheating. This will require investigation of operative temperatures and comparison with design predictions. The Contractor is required to monitor the indoor environment by recording temperature and CO2 as well as energy consumption as described in Annex 2I: Controls. Performance in use temperatures for assessment of summertime conditions shall be monitored in typical north, south, east and west facing classrooms and in other key spaces, such as: atria, dining spaces, libraries, learning resource centres, admin and head teacher’s offices, server rooms and reprographics rooms, and recorded as part of Building Performance Evaluation, See GDB Section 2.14.6: Building Performance Evaluation (BPE) and seasonal commissioning. Performance in Use Standard for Overheating The following performance in use (PIU) criteria shall be used. It shall be possible to demonstrate within spaces that are occupied for more than 30 minutes at a time that, during the school day, the average internal air temperature does not exceed the average external air temperature measured over an occupied day by more than 5ºC; both temperatures being averaged over the time period when the external air temperature is 20ºC, or higher, except when the diurnal temperature range (lowest temperature from the previous night to the maximum daytime temperature the following day) is less than 4ºC. The buildings shall be able to achieve temperatures within the acceptable range when windows, fans and ventilation systems are operated to reduce summertime temperatures, and the space has the intended number of occupants, numbers and types of computers, data projectors and other ICT equipment. Note: overheating criteria are for the thermal comfort of occupants and are not applicable for equipment such as in server rooms. The extra heat loads from cookers in food and Bunsen burners in science that occur intermittently should be considered separately. If a space fails the PIU criteria above and the internal recorded air temperatures exceed Tmax for Cat III, the Contractor shall examine the temperature records
temperatures described below then the Contractor or a heating expert should be asked to consider if the building is overheating. This will require investigation of operative temperatures and comparison with design predictions. The Contractor is required to monitor the indoor environment by recording temperature and CO2 as well as energy consumption as described in Annex 2I: Controls. Performance in use temperatures for assessment of summertime conditions shall be monitored in typical north, south, east and west facing classrooms and in other key spaces, such as: atria, dining spaces, libraries, learning resource centres, admin and head teacher’s offices, server rooms and reprographics rooms, and recorded as part of Building Performance Evaluation, See GDB Section 2.14.6: Building Performance Evaluation (BPE) and seasonal commissioning. Performance in Use Standard for Overheating The following performance in use (PIU) criteria shall be used. It shall be possible to demonstrate within spaces that are occupied for more than 30 minutes at a time that, during the school day, the average internal air temperature does not exceed the average external air temperature measured over an occupied day by more than 5ºC; both temperatures being averaged over the time period when the external air temperature is 20ºC, or higher, except when the diurnal temperature range (lowest temperature from the previous night to the maximum daytime temperature the following day) is less than 4ºC. The buildings shall be able to achieve temperatures within the acceptable range when windows, fans and ventilation systems are operated to reduce summertime temperatures, and the space has the intended number of occupants, numbers and types of computers, data projectors and other ICT equipment. Note: overheating criteria are for the thermal comfort of occupants and are not applicable for equipment such as in server rooms. The extra heat loads from cookers in food and Bunsen burners in science that occur intermittently should be considered separately. If a space fails the PIU criteria above and the internal recorded air temperatures exceed Tmax for Cat III, the Contractor shall examine the temperature records
Annex_2F_Mechanical_Services_and_PHE__Technical_Annex_.docx