Describes the results of air tightness tests of various service penetrations through a polythene vapour barrier and associated insulation. The service penetrations studied were insulated and uninsulated ventilation ducts, plastics, pipes, electrical boxes and electrical conduits. Various methods of sealing the penetration were tested for each case. Recommendations are made for choice of sealing method based on performance and case of installation. Examples are given of the effect of leakage through service penetrations on total building leakage.
Reviews the energy conservation features employed in most low energy houses in the Prairie region including airtightness (by application of a vapour barrier), increased thickness of insulation, air-to-air heat exchangers and south-facing windows. Discusses the performance of low energy houses in Saskatoon, and the cost of energy conservation features.
States that in a tight house with a vapour barrier, an air management system is needed to provide fresh air and remove the build-up of moisture generated by the occupants. Briefly describes a typical air management system,incorporating an air-to-air heat exchanger, and discusses the need to provide an acceptable ventilation rate, which controls pollutant level but minimizes heat losses.
Gives answers to practical problems encountered when retrofitting older Canadian houses. The first section gives an overview of a typical house both before and after retrofitting. The second section gives detailed answers togeneral questions covering ventilation, moisture and condensation, air barriers (sealing a house), vapour barriers, insulation, basements, walls, attics, roofs, windows, doors, weatherstripping, caulking, air quality, heat recovery and heat loss testing.
Notes the high heat loss in Canadian houses due to air leakage and condensation problems caused by uncontrolled moisture movement into the exterior wall structure. Recommends the installation of an air-vapour barrier to form a completely sealed envelope around the house structure except at doors, windows, vents and other obstacles. The recommended thickness for the polyethylene sheet of the air vapour barrier is 6mm, which is continually sealed at all joints. Details the recommended installation procedures for realising an air-vapour barrier.
Shows that efficient moisture removal in a ventilated roof via ventilation openings is a function of roof length. Beyond a certain critical length all moisture diffusing in from below will be deposited in the roof. The critical roof length will be greater the more vapour tight the section beneath the roof space is. If a vapour barrier is necessary, as in an unventilated roof, it maybe that an unventilated roof is preferable in the first place.
There are two types of air movement in the shell of a building - movement along the insulation as in cavity walls and movement through the insulation. Generally the heat losses due to the faults in the inner lining of the vapour barrier and the consequential air movement through the shell are much bigger then losses due to faults in the insulation - they cannot be compensated for by using tighter wind protection.
Defines types of condensation occurring in houses and describes practical ways for the householder to control surface and concealed condensation. Gives instructions to builders for installing air/vapour barriers to meet the required standards, and shows ways in which ventilation can control condensation.
Describes details of wall and foundation designs that have been used in constructing super-insulated houses on the Canadian prairies. One trend has been the development of the double framing system in which two sets of wall studs are used one
Outlines a method for measuring the air leakage through the surface exteriors of an apartment, by adjusting the pressure of the adjoining apartments to that of the test apartment, so that no air leakage occurs through adjoining walls.