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Adding outdoor air in hot humid climates causes moisture problems right? Sometimes. It depends on the condition of the house before you start to add outdoor air. Contrary to popular belief, most… Read More

The function of a vapor barrier is to retard the migration of water vapor. Where it is located in an assembly and its permeability is a function of climate, the characteristics of the materials that… Read More

Controlling rain is the single most important factor in the design and construction of durable buildings and in the control of mold. Drainage planes are used in the design and construction of… Read More

Controlling heat flow, airflow, moisture flow and solar and other radiation will control the interactions among the physical elements of the building, its occupants and the environment. Of these four… Read More

Buildings used to be constructed over cellars. Cellars were dank, dark places where coal was stored. People never intended to live in cellars. Now we have things called basements that have pool… Read More

Attics or roofs can be designed and constructed to be either vented or unvented in any hygro-thermal zone (Map 1). The choice of venting or not venting is a design and construction choice not a… Read More

Building form and orientation do not have as large an impact on energy consumption as sometimes thought, especially for mid-size or large buildings. In all buildings, the ratio of enclosure area to… Read More

In traditional mass walls, e.g. a wall of solid masonry or earth, the resistance to rain penetration was only one aspect of enclosure performance (Photograph 1). Heat flow was also controlled by the… Read More

Airtightness testing has long—since the 1980’s—been used to test high-performance housing. The 2012 version of the International Residential Code requires testing of every new home. Recently there… Read More

The design of building enclosures to control rain penetration and control rain shedding is typically based on experience and rules of thumb that make use of traditional details. Unlike heat flow,… Read More