The following data needs to be specified or derived in some manner. Software developers may use any acceptable method to determine the data. For instance, zip code could be entered and every thing else could be derived from this. Alternatively, state, county and city could be entered and the other variables could be derived from those. If the software allows for the parameters to be individually specified, then data validation should be employed to verify that the inputs are consistent with each other. Standard 90.1 Appendix B maps U.S. states and counties to the climate zones. Standard 90.1 Appendix D maps U.S. states and cities to additional climate information, including design temperatures.
Zip Code |
|
---|---|
Applicability |
All projects |
Definition |
One of approximately 44,000 postal designations in the United States |
Units |
List or text |
Input Restrictions |
None |
Baseline Rules |
Not applicable |
Latitude |
|
---|---|
Applicability |
All projects |
Definition |
The latitude of the project site |
Units |
Degrees (º) |
Input Restrictions |
None |
Baseline Rules |
Same as proposed design |
Longitude |
|
---|---|
Applicability |
All projects |
Definition |
The longitude of the project site |
Units |
Degrees (º) |
Input Restrictions |
None |
Baseline Rules |
Same as proposed design |
Elevation |
|
---|---|
Applicability |
All projects |
Definition |
The height of the building site above sea level |
Units |
Feet (ft) |
Input Restrictions |
None |
Baseline Rules |
Same as the proposed design |
DOE Thermal Zone |
|
---|---|
Applicability |
All projects |
Definition |
One of 9 thermal zones defined in ASHRAE 90.1-2004 and later. These are numbered zero (0) through 8. Used to determine building envelope and other criteria. |
Units |
List |
Input Restrictions |
None |
Baseline Rules |
Same as proposed design |
DOE Moisture Zone |
|
---|---|
Applicability |
All projects |
Definition |
One of three moisture zones defined in ASHRAE 90.1-2004 and later |
Units |
List: Moist (A), Dry (B), or Marine (C) |
Input Restrictions |
None |
Baseline Rules |
Same as the proposed design |
Time Zone |
|
---|---|
Applicability |
All projects |
Definition |
The time zone measured from GMT |
Units |
List |
Input Restrictions |
Typically derived from other inputs such as zip code or state |
Baseline Rules |
Same time zone as the proposed design |
Daylight Savings Time Observed |
|
---|---|
Applicability |
All projects |
Definition |
An indication that daylight savings time is observed. The schedules of operation are shifted by an hour twice a year and this affects of solar gains, temperature and other factors |
Units |
Boolean (True/False) |
Input Restrictions |
Typically derived from other inputs such as zip code or state |
Baseline Rules |
Same as the proposed design |
State |
|
---|---|
Applicability |
All projects |
Definition |
State where the project is located |
Units |
List |
Input Restrictions |
None |
Baseline Rules |
Not applicable |
County |
|
---|---|
Applicability |
All projects |
Definition |
The county where the project is located |
Units |
List |
Input Restrictions |
None |
Baseline Rules |
Not applicable |
City |
|
---|---|
Applicability |
All projects |
Definition |
The city where the project is located |
Units |
List |
Input Restrictions |
None |
Baseline Rules |
Not applicable |
Design Day Data |
|
---|---|
Applicability |
All projects |
Definition |
A data structure indicating design day information used for the sizing of the proposed system. Note that this information may not necessarily match the information used in the annual compliance simulation. |
Units |
Data Structure: contains the following: Cooling Design DB (1%), Cooling Design Wet-Bulb (1%), Heating Design Temperature (99.6%) |
Input Restrictions |
Must match climate data in Standard 90.1, Normative Appendix D. |
Baseline Rules |
Not applicable |
Weather File |
|
---|---|
Applicability |
All projects |
Definition |
The hourly (i.e., 8,760 hour per year) weather data to be used in performing the building energy simulations. Weather data must include outside dry-bulb temperature, outside wet-bulb temperature, atmospheric pressure, wind speed, wind direction, cloud amount, cloud type (or total horizontal solar and total direct normal solar), clearness number, ground temperature, humidity ratio, density of air, and specific enthalpy. |
Units |
Data structure |
Input Restrictions |
The weather file selected shall be in the same climate zone as the proposed design. If multiple weather files exist for one climate zone then the weather file closest in distance to the proposed design and in the same climate zone shall be used. Weather data should be representative of the long term conditions at the site |
Baseline Rules |
Weather data shall be the same for both the proposed design and baseline building |
Ground Reflectance |
|
---|---|
Applicability |
All projects |
Definition |
Ground reflectance affects daylighting calculations and solar gain. The reflectance can be specified as a constant for the entire period of the energy simulation or it may be scheduled, which might be appropriate to account for snow cover in the winter. |
Units |
Data structure: schedule, fraction |
Input Restrictions |
Default of 0.30 |
Baseline Rules |
Ground reflectance shall be the same for both the proposed design and the baseline building when it is specified to capture snow cover. When specific design features are incorporated to increase or reduce reflectance for the purpose of enhancing daylighting, there can be variation between the proposed design and the standard design, when appropriately documented. |