English

An overview of the availability, performance and application of inlets for natural supply of ventilation air and the consequences on indoor air quality and comfort

The objective of the study described in this report is to identify barriers restricting the implementation of natural or simple fan assisted ventilation systems in the design of new office type buildings and in the refurbishment of existing such buildings. The perceived barriers are identified in an in-depth study with structured interviews based on questionnaires among leading designers and decision makers.

The rainscreen principle is not new. lt was proposed as early as the mid sixties by researchers of the Division of Building Research of the National Research Council of Canada and the basic principles were developed. lt has been applied to certain exterior wall types but the performance of rainscreen walls remains largely unknown because of the absence of engineering data.

The objective of the study described in this report is to identify barriers restricting the implementation of natural or simple fan assisted ventilation systems in the design of new office type buildings and in the refurbishment of existing such buildings. The perceived barriers are identified in an in-depth study with structured interviews based on questionnaires among leading designers and decision makers.

Use of Brick Veneer/Steel Stud wall systems has preceded adequate forma} scientific investigation into its long term serviceability and safety. Of particular interest to many parties is the performance of the wall system under typical winter conditions encountered in cold climate regions of Canada. In this study, experimental investigations of three types of Brick Veneer/Steel Stud wall systems were performed using a specially built apparatus used to provide air pressure, temperature and vapour pressure differentials across test specimens.

Morrison Hershfield Limited undertook to study and investigate the performance of the Rainscreen Principle applied to residential claddings on wood frame construction for the Canada Mortgage and Housing Corporation. The study included a full scale simulation, in the laboratory, of the rain penetration control performance of three cladding types with each having a sealed and leaky air barrier system. The three cladding types include vinyl siding, stucco, and a brick veneer. Ail cladding systems were mounted on a conventional wood frame wall.

Clients, designers and institutions are all calling for more airtight buildings. Do we need mandatory pressure tests backed up by compliance procedures in Part L, or simply the publication of good practice guidelines? A recent CIBSE workshop delivered some answers.