Summer Design Day

Cooling Design tab on Model Options dialog.

 

Day

Select the day of the month for the design day. The default day is 15, i.e. the middle of the month.

 

This data is only used to define the solar path over the design day and does not affect temperatures etc which are defined at site level.

Note: This same day of the month will be used for all months selected below when using the 2-Multiple design months Design temperature period.

Month (or Start month and End Month)

Depending on the selection at site level for Design temperature period, you can either select a single design month (when it is set to 1-Single design month) or a month range (when it is set to 2-Multiple design months).

 

When a single month is being used, the default design month will be 1 month after the month of mid-summer by default (July in the Northern Hemisphere, January in the Southern Hemisphere). When multiple months are being used, the default start month is the mid-summer month and the end month is 2 months later. This covers most design cases where peak conditions may occur significantly later after mid summer, especially when there are large amounts of South-facing glazing (in the Northern Hemisphere).

Important Note: If you are using the default 1-Single design month Design temperature period option the design temperature and humidity values used in the calculations will be the “Yearly” design temperatures set at site level under Summer Design Weather Data. This is true regardless of the month and day of month selected on the Cooling design calculation options dialog. You will therefore find that the outdoor air temperatures won’t change when changing the month with this option set. You must use the to 2-Multiple design months option to see seasonal variations of design outside air conditions.

Tip: Use the 2-Multiple design months Design temperature period option for a thorough analysis. DesignBuilder will sequentially test various monthly temperature and solar radiation profiles to automatically identify the peak cooling month on your project.

Day of week

This selection is used to identify the appropriate daily profile within the schedules to use for the Cooling design calculations. The day type should be the day when the most extreme conditions and highest cooling loads are expected. You should normally keep the 9-SummerDesignDay default option, especially when also running simulations. Select the day of week from the options: