16-0808 v3.1/Pikes Peak Summit Complex/Operable Windows in Extremely Cold Environment


Our team is seeking an exception for providing operable windows in regularly occupied spaces due to the unique nature of the site and climate in our project at 14,115 feet above sea level. Our reasoning for this is as follows:

1.       The climate at this site is extremely cold and is not conducive to natural ventilation. 65% of all annual hours are below freezing, with 48% of all hours being below 23 degrees F. As indicated in a weather file that uses on-site temperatures (see attached), only 76 hours per year are in the 50-59F range, with none above 59F. Typically, exterior temperatures should be above 60F to avoid to allow for the use of natural ventilation without causing thermal comfort problems.

2.       From a biomimetic standpoint, opening up windows causes heat to be lost to the outdoors and organisms in this climate would evolve to avoid these losses. Our daily weather files indicates that any solar gains captured in the 50-59F range is needed that night as the temperatures will again drop below freezing. Our current approach favors capturing heat and preserving it through the night (using heavy mass and phase change materials). This approach more accurately replicates nature in an arctic environment, such as caribou and other large mammals that have respiratory systems designed to minimize heat loss (Mammalogy: Adaptation, Diversity, Ecology - Feldhamer, et. al) 

3.       The team has considered alternatives to operable windows such as vents and louvers. These are still limited by the number of hours that the ambient temperature makes them beneficial. Additionally, even “low leakage” dampers allow for excessive infiltration in this environment where wind gusts regularly exceed 100 MPH. 

4.       Understanding the importance of fresh air though in all environments, including this harsh one, we believe that increasing the ventilation rates above ASHRAE 62 requirements in staffed areas would achieve a high-quality indoor environment. If this approach is acceptable, we would like guidance on determining the appropriate metrics and what items would need to be measured (CO2, VOCs, etc.). We believe that Harvard’s recently published, Associations of Cognitive Function Scores with Carbon Dioxide, Ventilation, and Volatile Organic Compound Exposures in Office Workers could be a resource to cite appropriate targets. 


The team has made the case that the project will function as a refuge from extreme outdoor conditions and that operable windows are not a viable option for accessing fresh air because of the extreme temperatures and wind. However, there is still a need to address occupant control, particularly on the rare occasions when weather permits. The team must still make a case for how the project's regular occupants (i.e. staff, not visitors) have occupant control over their connection to the outdoors and fresh air while working in the space in order to make use of the following new Exception:
I07-E5 Refuge in Extremely Cold Climates
Projects providing refuge in extremely cold climates do not need to have operable windows in all spaces, but must still provide occupants with control over their connection to the outdoors and fresh air at staffed workstations. Teams must make a case, through the Dialogue, that alternatives to operable windows are not generally viable due to the extremely cold conditions of the site, that a direct connection to the outdoors is provided through views and at least one exterior gathering space, and that regular occupants are able to control their access to fresh air and the outdoors when conditions permit. 
I07-c Exception Narrative - A 1-2 page narrative explaining how the project meets the criteria of this Exception.

Post ID 6009

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