Designs That Work
Cold Climate
Introduction - Building for a Cold Climate
A Cold climate is defined as a region with approximately 5,400 heating
degree days or more, but fewer than 9,000 heating degree days. In North
America, most cold climates vary in annual precipitation from less than 20
in. to more than 60 in. Condensation of warm interior air on cold surfaces
within the building assembly is a concern in design and construction. In
addition, in many areas ground water presents a concern because most
houses are built with basements or crawl spaces. Rain, snow, and ice
damming represent threats to the integrity of the building envelope.
Until recently, the focus in terms of moisture control in cold climates
was moisture drive from the interior during the heating season. The
widespread introduction of centralized cooling in cold climates, however,
can produce cold interior surfaces on which warm moist air infiltrating
from the exterior can condense during the summer. If interior vapor
barriers are installed in conjunction with air conditioning, serious
moisture problems can occur. Interior vapor barriers should be avoided in
this climate region. Controlling moisture and air flow in the building
envelope in this climate is critical to designing and building a durable,
comfortable home.
Note: Don’t forget that it is always the conditions that you
actually experience in your area that determine the appropriate building
design and construction details. The Building America Climate Zones
provide simplified groupings of geographic locations that may actually
vary greatly in terms of weather, and therefore should be viewed as
guidelines.
Map 1: Annual Precipitation - North America
Map 2: The Building America Hygro-Thermal Regions
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