If you reside in a high-altitude area of the country such as Denver, your roofing needs will certainly differ from your low-altitude counterparts. High altitude roofs contend with thinner air and an increased level of solar radiation which, combined with higher snow totals and water vapor, make for unique considerations when maintaining a roof.
A “cold roof” design is recommended for areas of higher elevation; this type of roof offers more ventilation and uses strategic placement of insulation above the ceiling, rather than between roof rafters. There are also roofing products that can be installed below your roof deck that can help release water vapor build up. This increased ventilation allows air to freely flow without getting trapped and causing the outside roof temperature to warm excessively.
Solar radiation is also a major factor in higher elevations since it can cause snow to melt even if surrounding air temperatures are 20º or below. This discrepancy between roof temperatures and ambient air temperatures becomes cause for concern when ice damning begins to occur, especially around roof eaves. Both latitude and elevation also come into play; in the springtime, solar radiation is more intense in northern regions, whereas areas to the south are more vulnerable toward the end of winter.
In the mile high city of Denver, cool days and even colder evenings are common due to less atmosphere present. Unable to hold the heat on the ground, the thin air at high elevations means greater heat loss at night as well as increased radiant heat while the sun is shining. This is a potentially problematic situation, especially for roofs since water vapor can easily become trapped within roofing layers.
In general, a well pitched and simply designed roof fare best in high altitude. Dormers, skylights, and low-sloping roofs can work in mountain roof designs, but if it’s possible to avoid these features it may help the longevity of your roof’s life.