Climate Design Tools 

The University of Idaho Integrated Design Lab produced a series of climate design resources to help assist in the conceptual and early design of passive strategies.  The creation of these tools was funded by the Idaho Power Company and was developed into two generations of spreadsheet calculators that are capable of analyzing building loads and the energy consumption impacts of a range of different design strategies.  With the permission of IDL-Boise, IDL-Bozeman has adapted these tools to reflect six reference cities in Montana.  You can download the tools for each of the six cities in Montana at the bottom of this page.

Currently, there are seven different calculation spreadsheets that span across two different generations of tool development:



Heat Gain Calculations

Cross Ventilation

Stack Ventilation

Night Ventilation Thermal Mass



Balance Point Calculation

Passive Solar

Earth Tube


Each spreadsheet contains multiple tabs and a step-by-step process that directs the user to define the critical baseline and performance parameters of the building.  These factors are linked to pre-defined equations within the spreadsheet that automatically provide the peak cooling loads, cooling capacities, and describe other critical design criteria.  Charts, line graphs, and other forms of graphic information also automatically populate the workspace to provide rich visual feedback to the user.  The spreadsheets also contain a reference tab that consolidates a myriad of textbook, code, and other sources needed to complete the step-by-step instructions.  Additionally, a variety of weather data, including hourly information from TMY weather files, are embedded into the calculations based upon six different reference cities within Montana.  Once each tab is filled out, the results pages of the spreadsheets contains all of the important outputs needed to evaluate how much the passive design measure can contribute to the peak loads or energy savings of the building.  Changes to the building parameters are instantaneous, making the Climate Tools package an ideal instrument to explore different design iterations and how they might facilitate passive design strategies.



The ultimate goal of the Climate Tools package is to reduce the loads and energy consumption of a building through passive design measures.  This happens mainly by embedding, early in the design process, the analysis of the performance capabilities of different passive cooling and heating strategies.  Once a performance capacity is calculated and compared against peak loads of a building, a qualitative decision can be made whether or not to pursue more detailed analysis.  If certain passive strategies are proven to meet some or the entire peak load, this may warrant further development.  Potential next steps could involve more advanced analysis such as building simulation to quantify annual energy savings based on actual weather data.

For more information, please visit the Integrated Design Lab Boise.

Bozeman, Montana Climate Tool Set
Billings, Montana Climate Tool Set
Great Falls, Montana Climate Tool Set
Helena, Montana Climate Tool Set
Kalispell, Montana Climate Tool Set
Missoula, Montana Climate Tool Set