Literature Review on Building Envelope, Heating and ... - Beeshive.org

Executive Summary
Canada’s regions north of 60 degrees of latitude occupy over 70% of the nation’s area,
but are populated by less than 1% of the nation’s population. Housing designs in
Northern Canada are imported from southern regions. As a result, building durability is
poor, which affects the quality of the built environment and energy budgets as well as the
global environment. The Heat and Moisture Performance of Envelopes group of the
Building Envelope and Structure program of the National Research Council of Canada,
has started a four-year project to develop durable, energy-efficient wall assemblies that
can accommodate the challenges of environmental conditions in Northern Canada as well
as along northern coastal regions.
The main objective of Task 2 of the project is to provide a knowledge base for selecting
building envelope assemblies to investigate in the analysis tasks of the project. This
includes conducting a global literature search to identify technologies, practices, and
issues for buildings subjected to extreme environmental conditions. This report
documents the findings of the literature review, which includes significant information on
practices, issues, and technologies regarding building envelopes, construction, heating,
ventilating, indoor air quality, utilities, and socio-housing issues. The literature review
also includes example building constructions from the arctic, Antarctica, Scandinavia, the
Himalayan region, Japan, as well as indigenous architectures’ climate adaptation.
Climate Outdoors
Climate in the arctic and sub-arctic regions varies considerably, particularly, above and
below the tree-line regions. Variations include the snow drifting pattern, wind,
temperatures, annual amounts of sunshine, and daylight. For example, in the NWT,
temperatures range from -45ºC (-49ºF) in winter to 35ºC (95ºF) in summer. Precipitation
is mainly in the form of snow with an annual range from 140 mm (5 ½ in.) in Hay River
to 425 mm (16 ¾ in.) in Inuvik. High winds and blizzards are common. Daylight, in
particular, is extremely variable. It ranges from almost 24 hours of daylight daily in
summer with the sun setting just before midnight and rising a few hours later, to very
little daylight in winter. In Alaska, low temperatures can range from -57ºC (-70ºF) for
weeks in interior areas to -34ºC (-30ºF) in south central and western areas and last for
extended periods. Wind speeds in excess of 200 km/h (125 mph) are common.
The maritime climate, dominated by ocean influences, is humid and temperate.
Precipitation occurs in all seasons, and might change by the hour. The weather could
come from any orientation. Summers are cool and short. Winters are mild and short with
some frost but not continuous snow. Spring and fall are extended in length. There are
small differences between monthly mean temperatures.
Climate Indoors
As an example, indoor air temperatures in NWT homes averaged from 21ºC to 28ºC
(70ºF to 82ºF), RH ranged from 9% to 46%, with an average of 25%, and air change rates
varied from 0.042 ach to 2.2 ach. A 20% RH indoors is considered optimum during an
PERD-079: Task 2 - <strong>Literature</strong> <strong>Review</strong>
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