English

The symposium aimed to address the merits and drawbacks of various requirements for residential ventilation along with the problems encountered in implementing these requirements. Discusses proposed and existing ventilation standards and codes in the United States and Canada. Presentations included investigations of site-built as well as manufactured homes and highlighted issues relating to implementation, IAQ, energy, moisture and economics. Also discusses the advantages and disadvantages of requiring mechanical ventilation in residences.

Describes the results of the experimental evaluaton of two precast concrete sandwich panels. States that for best results for precast concrete walls, the air barrier must be sufficiently airtight to achieve static pressure equalization and there must be sufficient venting to achieve dynamic pressure-equalization. Similar results were obtained from research conducted on other wall systems. For precast concrete walls, these results are best obtained by minimizing the cavity volume and decreasing air barrier leakage before increasing vent area.

Describes the experimental evaluation of a brick veneer steel stud (BVSS) test specimen. The system was evaluated for air leakage characteristics, pressure equalization response, deflection and water penetration. Concludes that for best results for BVSS walls, the air barrier must be sufficiently airtight to achieve static pressure equalization and there must be sufficient venting to achieve dynamic pressure equalization. Similar results were obtained from research conducted on other wall systems.

Describes a research and development project that has been started in order to generate design guidelines for PER walls. The three tasks covered are computer modelling, experimental evaluation and development of design guidelines. Describes the results of the experimental evaluation of an exterior insulation finish system. The systems were evaluated for air leakage characteristics, pressure equalization response and water penetration. Concludes that a wall designed to PER principles is more able to resist rain penetration.

Presents a simplified CFD interface (SCI) intended to allow architects and building engineers to use CFD with little training. It can be easily integrated into new CFD programs.

Describes how a new aerosol spray technology can allow weatherization crews to seal even tiny duct leaks in places that are difficult to reach using conventional methods.

The airtightness performances of buildings and ventilation systems can have a major impact on the indoor climate (IAQ, thermal comfort,...) and on the energy performance. Measurement results for Belgian buildings clearly show that the airtightness is often moderate to very poor. As part of the proposed energy performance legislation for the Flemish Region, it is envisaged to pay attention to the airtightness of buildings and ductwork. In the first part of the paper, results found for Belgian buildings and systems are briefly presented and discussed.

The main problem in natural ventilation is that its efficiency depends very tightly on the meteorological conditions : high wind velocity and outside temperature lower than inside are optimal conditions for efficient ventilation. Consequently, air renewal inside buildings is very fluctuating from one moment to another, and extreme comportments can be reached from one season to another : in winter, ventilation is usually very satisfying, whereas in summer unwanted reverse airflows can hardly be avoided.

Ventilation plays an important role in the RT 2000 regulation. This new French thermal regulation takes into account energy for heating and lighting through a C coefficient (primary energy in kWh), as well as summer comfort for non air-conditioned buildings. The paper focuses on the calculation of the C Coefficient. For the ventilation side of it, the calculation method aims both to have simple input data and physically based algorithms. The fact that it was chosen to have a computer based approach made this possible.

The aim is to develop a new method for comfort in settings with high thermal load in buildings that do not require continuous cooling but cooling only during shorter periods. Example of such buildings is schools. The present ventilation and control systems are designed for supply of air at a constant flowrate or to respond to relatively slow variations in load or step changes in load. The slow variations in load are mainly governed by the diurnal cycle and sudden step changes in load are mainly due to people entering or leaving a room.