Timing model Option

Data tab on Model Options dialog.


You can specify schedules in DesignBuilder using two approaches:



Generally if you start to find the Typical workday timing mode too restrictive you should switch to Schedules mode.


See also the Timing, Schedules, Profiles and Holidays Tutorial


You can also request:

Timing HVAC + natural ventilation operates with occupancy

Select this option if all heating, cooling, natural ventilation and DHW operation follows occupancy.


This option is only available if Timing is set to Typical workday.


Note that HVAC operation data can modify the HVAC operation even when Timing HVAC + natural ventilation operates with occupancy is set. For example:



These differences are applied as 'modifiers' to the basic occupancy schedule because HVAC systems generally switch on and off based on the occupancy time but with differences. e.g. Heating systems are often switched off in summer, they may operate during weekends when the building is unoccupied and they will often have a preheat period to get the building up to temperature before occupancy.

Internal gains operate with occupancy

Select this option if lighting and other internal gains operation follows occupancy. If you wish to enter specific schedules for lighting and/or other internal gains you should uncheck this option. For example there may be low levels of emergency lighting and some IT equipment usage while the building is unoccupied.