The Parliamentary Precinct in Ottawa, Canada, is comprised of a number of historic buildings that include the House of Commons, the Senate Chamber, the Parliamentary Library, the Peace Tower, and other buildings that provide offices for parliamentarians and their staff. The majority of these buildings have exterior walls that are made of solid masonry with thicknesses ranging between 400 mm and 800 mm. In some cases, special wall areas are more than 1200 mm thick and are comprised of various types of masonry materials. With winter design temperatures of-25°C, more than 170 cm of snowfall, and numerous thaws during the five month heating season, the exterior environmental conditions acting on the exterior wall assemblies of these historic buildings are severe enough to cause masonry and mortar deterioration wherever moisture accumulates during winter months.Infrared thermographic inspections were carried out to locate and identify the causal mechanisms of moisture accumulation within masonry wall assemblies. This paper will discuss the types of thermal patterns produced by various mechanisms of heat loss and identify some of the typical areas where possible masonry deterioration occurs. Knowledge gained from these extensive investigations will be used to develop a nondestructive test methodology to locate areas of freeze-thaw damage as part of a predictive and preventive maintenance program to reduce preservation costs of these historical structures.
In cold climates, air leakage is accompanied by moisture transport. When migrating through dew point temperatures, a considerable amount of moisture accumulation may occur depending on variables such as the duration of sub-zero exterior temperatures, building pressurization, wind effects and the level of interior relative humidity. Moisture accumulation may result in premature deterioration of wall assemblies and the formation of mould. When commissioning new building envelopes, or carrying out building condition inspections of existing building envelopes, it is imperative to differentiate the source of the moisture accumulation since the recommendation for remedial action will vary considerably. This paper will define the various types of thermal patterns created by surface penetration of water versus those patterns created by air leakage from the building interior in cold winter conditions. Various types of exterior masonry building envelopes will be discussed along with their hydrothermal performance characteristics and how these affect thermal patterns during various inspection procedures.
Thermal comfort complaints within work places are one of the leading causes of workforce productivity loss within office environments. Generally, mechanical systems are relied on to provide adequate indoor environments. In many situations, these systems cannot provide suitable work environments due to unacceptable asymmetrical radiant temperature conditions found in exterior zones of building interiors. Public Works and Government Services Canada (PWGSC) has developed methodologies using infrared technology to assist building and office managers in reducing thermal comfort complaints and improve workforce productivity. Detection, verification, remediation and commissioning of solutions are easily and effectively carried out with the assistance of infrared radiometers and proper inspection and analysis procedures. This paper will outline two case studies and detail methodologies used in each case.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.