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In 1995, a joint research project 1 with the Institute for Research in Construction was initiated to assess the in situ thermal performance of a number of insulation products used as exterior basement insulation in contact with the ground. Sixteen insulation specimens measuring 610 mm and 1220 mm wide were installed on the exterior basement walls of an experimental building, test hut no. 1, located on NRC campus in Ottawa. These specimens were instrumented prior to backfilling and their thermal performance was monitored over two full years. Soil temperatures and moisture content were monitored concurrently. Weather events were recorded daily. This paper focuses on the performance of the two spray polyurethane foam (SPF) specimens assessed in this experiment. Through analysis of the surface temperatures of the specimens, water movement was detected at the insulation/soil interface through various periods of heavy rain and major thaws throughout the two-year period. Over the same period, the surface of the concrete on the inside of the insulation showed no evidence of water penetration through the SPF layer. The insulation specimens were retrieved after 31 months of exposure in the soil. Good and continuous surface adhesion was also noted on removal. Samples were taken from these exposed specimens. When tested in the lab, after recovery and drying of the specimens, the compressive strengths of the SPF samples were slightly higher than those tested at the beginning of the experiment. For the conditions recorded over two years of monitoring, the thermal performance of each insulation specimen was found to be stable through the heating season. The thermal performance appeared not to be significantly affected by water movement at the exterior face of the insulation. One SPF specimen showed steady thermal performance through two heating seasons while the other actually improved in the second year. It was concluded that the key performance factors of the 76 mm thick SPF specimens sprayed on the exterior surfaces of the concrete basement wall all remained at a very good level, i.e., the in situ thermal resistance, the compressive strength, and the moisture contents of the specimens.

Foam plastic thermal insulations have substantially replaced traditional insulations in low sloped roofing systems in North America. Foam plastic thermal insulations used in low sloped roofs are low density (typically 16–48 kg/m3) materials with low permeability to air and water vapour. In many roofs these materials have been directly substituted for traditional (wood and glass fibre) insulations without due attention to the different material characteristics. Moist air movement within roofs,condensation protection (air and vapour barriers),steel deck corrosion,roof membrane blistering and roof traffic damage are discussed. This paper discusses protection of foam plastic thermal insulations in roofing systems, why the protection is needed,and what consequences result if these materials are not protected. Case studies demonstrate the importance of condensation protection in reducing corrosion of galvanized steel in roofs containing closed cell phenolic foam roof insulation in Canada.

Polyisocyanurate (polyiso) foam insulation with impermeable facers is known for its superior insulating properties in building envelope applications. The impermeable facer on both sides of polyiso foam insulation board is designed to increase and maintain the long-term thermal resistance (LTTR) of the insulation. Currently, the Institute for Research in Construction (IRC)/National Research Council (NRC) of Canada, in association with the Canadian Polyisocyanurate Council, has embarked on a researchproject to develop a standard test methodology that would help to quantify the design LTTR value of polyiso foam insulation boards with impermeable facers. This paper outlines the research project and presents preliminary test results from experimental work. These preliminary results are discussed with a view to developing a methodology that will be used as the basis for a National Standard in Canada for the determination of LTTR of polyiso foam insulation with impermeable facers., 4th Symposium on Insulation Materials : Testing and Applications - ASTP STP 1426: 21 October 2002, Charleston, South Carolina, U.S.A.

As industry began to evaluate CFC-replacements, it became apparent that foam performance characterizations have been based primarily on empirical evidence collected over a long period of gradualimprovements. Much of the existing wealth of knowledge was simply not applicable to new systems. The development of new products with CFC replacements requires understanding how formulation variables(polyol, isocyanate, blowing agent, catalyst) and manufacturing conditions affect foam properties, how conditions in use affect foam performance and how the process of sample selection and testing may be used to provide feedback to design improved foams., Also presented at the World Congress : Polyurethane '93

Reprinted as IRC Paper, IRC-P-3355, NRCC 36108. The publication is stored in the NRC Archives., Polyurethanes World Congress: 10 October 1993, Vancouver, BC, Canada

The technology for manufacturing high thermal performance cellular plastic insulations such as polyurethane, polyisocyanurate, phenolics and extruded polystyrene uses gases with low thermal conductivity as captive blowing agents. The gas is captured in the closed cells of the material to achieve higher thermal resistance. But once in contact with the atmosphere, the thermal resistances of these materials gradually decrease. This phenomenon is called aging.

A non-destructive technique, involving specimen encapsulation and determination of the dependence of thermal resistance on temperature, to measure the blowing agent pressure in cellular plastic insulation was recently presented. This technique was applied to polyurethane foam manufactured with different blowing agents and the results were compared with those obtained from model calculations. The results indicate that the long-term solubility of the gas in the polymer matrix may differ from that determined from short-term experiments. The paper presents results for HCFC-123 and HCFC-141b as well as CFC-11 and discusses their implication for long-term thermal resistance of polyurethane foams., Also presented at the Polyurethane '90 : Proceedings of the SPI 33rd Annual Technical/Marketing Conference, September 30, 1990 in Orlando, Fl, USA

Moisture gains of three closed cell and one open cell foam plastic insulation were studied in the laboratory. The purpose of the study was to investigate the relationship between rates of moisture gain and temperature-moisture environment under laboratory conditions.

Also presented at the International Workshop on Long- term Thermal Performance of Cellular Plastics, September 28-29, 1989 in Huntsville, Ont., Canada, Polyurethanes '89 : Proceedings of the SPI 32nd Annual Technical/Marketing Conference: 01 October 1989, San Francisco, CA, USA

The results of a series of full-scale room burn experiments with foamed plastic insulation in two walls are discussed in this paper. The results indicate that the severity of room fires as characterized by the normalized heat load does not appear to be increased by the addition of foamed plastic insulation., Reprinted from: Fire Technology, v. 22, no. 1, February 1986, p. 5-13, ISSN: 0015-2684, DOI: 10.1007/BF01040240.

Water vapor transport through rigid polyurethane and polyisocyanurate foams was investigated using three test methods--two under isothermal conditions and one in the presence of a thermal gradient. All three methods yielded water vapor transmission coefficients of the materials. It is observed that the magnitude of the coefficients increases rapidly with temperature above 20 deg. C. In one of the isothermal methods called a modified cup method, developed at the Institute for Research in Construction, only the temperature has to be controlled and this is considered a definite advantage over the other method, ASTM Test Methods of Water Vapor Transmission of Materials, (E 96-80) dry cup method, in which both temperature and relative humidity are to be controlled. Further, the modified cup method also allows the determination of moisture accumulated in the test specimen during moisture transport. It was conclusively shown that during isothermal transport processes no moisture accumulates in either the polyurethane or the polyisocyanurate specimens. The accumulation and distribution of moisture in the presence of a thermal gradient was also investigated. Contrary to the isothermal process, the moisture transport in the presence of a thermal gradient acting in the same direction as the vapor pressure gradient results in the accumulation of large quantities of water in the foams. This phenomenon may be partly attributed to the temperature dependence of the water vapor transmission coefficients., Water Vapor Transmission through Building Materials and Systems : Mechanisms and Measurement : Symposium: 10 December 1987, Bal Harbour, FL, USA

This paper describes a method for measuring gas diffusion through cellular plastics A specimen is placed in a chamber, which is then scaled and pressur ized with the test gas. The pressure increase causes some gas to enter the specicmen, and this entry results in a reduction of the chamber pressure By following the change in chamber pressure with time an appropriate transport characteristic for the material is determined An application of this method to a core specimen of an extruded polystyrene board is presented.