Valuing air barriers.

Discusses the importance of selling the cost benefit of tight building practices in the absence of national or local codes or regulations to mandate well-sealed apartment buildings. States that studies carried out by the Canada Mortgage and Housing Corporation have found that air leakage in apartment buildings can contribute to as much as 20% of the annual space-heating energy load. It also represents a substantial proportion of the peak space-heating load.

A new technique for measuring airtightness of the building envelope using pulse pressurisation.

A pulse pressurization technique to measure the airtightness of the building envelope is developed. The governing equations are introduced and the procedure for deriving airtightness parameters from the pressure decay curve is shown. Pulse pressurization is supplied using a high-pressure air tank. The pressure decay after pulse pressurization is measured provides the air leakage equation for a test house.

Ventilation for people.

The developing trend that Building Regulations in the future will be applied to buildings in use rather than to their design intent on paper has many important implications. It will lead to pressure testing of new buildings to ensure air tightness, low energy bills and the associated absence of draughts. Importantly, it means that for the first time, the ventilation air will enter the building through the air inlet ductwork. This offers the designers the opportunity to control the indoor environment to create refreshing comfortable climate while retaining low energy use.

Energy impact of ventilation rates.

As heat exchanges through building envelopes and undesirable internal gains have been reduced in the last years due to energy conservation efforts, the importance of the energy needed to heat, cool and move outdoor air for ventilation has increased in relative tem1s. This study, developed within the European project TIP-VENT (JOULE) aims to study the impact of ventilation air flow rates upon the energy needs of typical buildings. Five real buildings were selected as case-studies: A hotel, an auditorium, an office building, a single-family residence and an apartment building.

The variation of airtightness of wood frame houses over an 11 year period.

This paper summarizes the most recent results from an ongoing, multi-year research program to monitor the long-term performance of residential air barrier systems. Airtightness tests were conducted on I 7 houses, located in Winnipeg, Canada, ranging in age from 8 to I I years, for which there was extensive historical data. Eight of the houses used polyethylene air barrier systems and nine used an early version of the airtight drywall approach (ADA). The latest tests were conducted in 1997.

Development of a field procedure to measure the airtightness of wall construction elements of houses.

Whole-house tests were developed to compare the airflow resistance of several different materials used to seal the walls of a house at the outer surface. These airflow resistances were measured infield installations and include the effects of interactions with adjacent materials and assemblies. The materials tested were housewrap over fiberboard and foam sheathings, extruded polystyrene foam sheathing with the edges taped, extruded polystyrene sheathing with the edges untaped, and caulking and foaming the inside of the wall cavity.

To storm or not to storm: measurement method to quantify impact of exterior envelope airtightness on energy usage prior to construction.

The purpose of this project was to devise a simple, experimentally validated method for quantifying the energy impacts of exterior envelope air leakage. Four full-size exterior envelope test specimens, two opaque wall systems and two fenestration systems, were built for determining simultaneous conductive and convective heat loss. The two opaque clear wall sections were metal-faced sandwich panel and cold formed steel frame.