English

Field measurements and numerical simulation were used to measure moisture transfer to the building envelope for a building with and without a vapour barrier. The results indicated that the vapour resistance of the barrier can be significantly below that provided by polyethylene, even in cold climates. States that moisture transfer from indoor air to the envelope can be seen as improving the indoor air quality by moderating the indoor humidity.

Experimental and simulation results are presented from an investigation of simultaneous heat air and moisture transport in a loose-fill insulation. The aim of the study was to investigate the thermal and moisture effects of natural air convection with no liquid transport present and to validate a numerical model. The structure was placed between two climate chambers at different temperatures. The quasi-steady-state temperature distribution in the cavity of the structure and transient moisture condition were measured, as well as the material properties.

Postulates that figures for the energy load of a building affected by infiltration may be too high because the simple formula used does not account for heat recovery within the building envelope. In the study, sensible heat transfer was simulated with the used of CFD in typical envelopes. The results confirmed a possible overprediction of energy load up to 95% at low leakage rates.

Mould, wet insulation, wet or weakened wood or premature aging of roof coverings often leads to the addition of extra ventilation in attics at time of renovation. The study develops a protocol to determine the effects, surveys several occupied buildings to establish why the ventilation was added, and establishes a base to analyse the effect of the installation.

The sessions in this conference covered: moisture control performance measurements; from the basement to the roof; moisture model inputs; wall design and building science; moisture model validation; wall performance; applied heat and moisture modelling; wall durability; whole buildings; fenestration practices; reducing foundation heat loss; roof design; green buildings; energy in buildings; building durability; fenestration principles; building performance; attics and roofs; indoor environment; low-slope roofs; mechanical systems; and workshops on a variety of topics.

Describes the post-construction HVAC system commissioning process done at a new historical museum and archival storage facility. Improper functioning of HVAC was discovered. The building was commissioned after occupation. The paper describes the process of rectifying the problems, and emphasises the importance of employing a commissioning agent throughout the design and construction process.

States that poor ventilation is a factor in raising humidity levels in well insulation cold climate housing. Aimed to look at the ventilation rates in houses with varying ventilation systems, noting indoor air humidity, domestic mite allergen levels and VOCs. Enzyme-linked immunosorbent assay was used to measure levels in 59 similar one-storey single family houses. 22 houses had an added mechanical supply and exhaust ventilation system.

An investigation was carried out in a multi-family building in New Jersey, USA of eight apartments, including resident interviews about air conditioner usage. Energy consumption for cooling varied widely across similar apartments, due to occupants' diverse beliefs about machine operation and economic considerations. 75% of residents did not use the thermostats, preferring to switch the system on and off according to comfort needs. Concludes that the problem is not lack of user education, but rather poor user-friendliness of air conditioner controls.

Mycological investigations were performed on a modern multistorey office building in the southeastern coastal US. Extensive colonization was found in the air handling units and fibreglass duct liner of the HVAC system. Concentrations in air samples were low however. Removal of colonized insulation material reduced indoor air quality complaints.

Describes a project to examine the secondary air filters in the air handling units on four floors of a multi-storey office building which had a history of fungal colonization of insulation in the air distribution system. Fungi were observed throughout the system. Lower concentrations of volatile organics were emitted from fungal affected air filter medium. Concludes that the growth of fungi in air distribution systems may affect the content of volatile organics in indoor air.