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Aussi disponible en français: Évaluation des panneaux porteurs isolés pour évaluer leur conformité au Code national du bâtiment

Also available in English: Evaluation of structural insulated panels for National Building Code compliance

Stucco or portland cement plaster is widely used in North America as an exterior cladding material for the wood-frame walls. Recent computer-based numerical simulation studies at the National Research Council (NRC) Canada, Institute for Research in Construction (IRC) have indicated that low liquid diffusivity and high water vapor permeability of the stucco material can positively influence the overall moisture management capacity of wood-frame stucco walls. This paper presents the results from experimental and numerical modeling studies carried out at the NRC-IRC on the development of high performance stucco materials and its effect on the overall moisture management capability of wood-frame stucco walls. Liquid water and water vapor transmission properties of several commercial/conventional stucco materials and some newly formulated compositions were measured and compared under laboratory conditions. The experimental results suggest that by appropriate choice of the mix composition, addition of a proper hydrophobic admixture, and using aggregates with a hydrophobic coating, stucco material with lower liquid water diffusivity can be produced without reducing the water vapor permeability. The results from the numerical modeling study show newly developed high performance stucco materials can significantly improve the moisture management capability of wood-frame stucco walls.

The thermal insulating efficiency of closed-cell foam insulation with a captive blowing agent changes over time during its service life in building envelope construction. Hence, the long-term thermal resistance (LTTR) value of closed-cell foam insulation has a great significance to the building envelope designers. Researchers at the National Research Council Canada Institute for Research in Construction (NRC-IRC) have worked on various aspects of aging characteristics of closed-cell foam insulation during the past two decades. This paper will provide a comprehensive scientific outline of the research activities that have been carried out at the NRC-IRC on the aging of closed-cell foam insulation and its practical implications on the North American construction industry., Third Global Insulation Conference and Exhibition: 16 October 2008, Barcelona, Spain

Moisture management in the building envelope plays an important role determining long-term durability and serviceability of Canadian houses. Improper or inadequate moisture management has caused severe damages in the Canadian houses. In many cases, building materials may not be able to compensate for deficiencies in the wall design and construction. Service life, as a result of these deficiencies, is shortened in the areas of heavy and sustained rainfall. In such a situation, it is important to develop a proper understanding of the mechanisms of moisture transport into and out of the building envelope, address the deficiencies, incorporate design features that will reduce moisture loading on the wall, and consider the modification of the hygrothermal properties of the building materials. In the latter case, such modifications of the hygrothermal properties of the building material can be engineered through innovative manufacturing technique and the material evolved through the process can lead to better moisture management in the building envelope., Le contrôle de l'humidité dans l'enveloppe de bâtiment joue un rôle important dans la détermination de la durabilité et de la tenue en service à long terme des maisons canadiennes. Au Canada, le contrôle de l'humidité insuffisant ou inadéquat a dans le passé causé d'importants dommages à des maisons. Dans de nombreux cas, les matériaux de construction pouvaient ne pas être capables de compenser les manques dans la conception et la construction des murs. La durée de vie utile, en conséquence de tels manques ou déficiences, se trouve raccourcie dans les régions à pluviosité forte ou soutenue. En pareille situation, il est important de développer une juste compréhension des mécanismes de la migration de l'humidité dans l'enveloppe du bâtiment et hors de celle-ci, de corriger ces manques ou déficiences, d'incorporer des caractéristiques de conception qui réduiront la charge d'humidité sur le mur et d'envisager la modification des propriétés hygrothermiques des matériaux de construction.

Efficient insulating systems are the key to the energy efficiency of a building envelope. Vacuum Insulation Panels (VIPs) offer excellent thermal resistance properties that can enhance the energy efficiency of insulating systems, use less space, and provide savings in energy consumption. However, from a Canadian perspective, VIP systems are little known and indeed unused in the building industry. There is a need to investigate the prospect of using VIPs in various components of building envelope. The long-term thermal insulating efficiency of the VIPs depends on its ability to maintain an adequate level of vacuum inside the panel. For design purpose the long-term thermal insulating characteristics of the VIPs needs to be understood and defined. This paper addresses some of the test methods that could accelerate the long term changes in thermal resistance and presents selected results from tests using elevated pressure, relative humidity and temperature on three types of VIPs., 10th Canadian Conference on Building Science and Technology, May 12, 2005, Ottawa, Canada

Aussi disponible en français: Le CCMC évalue un nouveau panneau isolé avec joints structuraux

Aussi disponible en français: Une nouvelle génération de systèmes d'isolation plus performants

International Conference on Building Envelope Systems and Technologies ICBEST 2001: 26 June 2001, Ottawa, ON

CCMC Evaluation Report 12969-R

A consortium 1 research project was initiated to determine the field performance of various thermal insulation products as applied in the exterior insulation basement system (EIBS). Initially a two-dimensional (2-D) analytical tool was used to derive the thermal transmission characteristics from an array of temperature measurements performed over a period of two years. Results immediately showed the influence of lateral heat flux between various products that differed in thermal transmission properties. Therefore, development of a three-dimensional (3-D) model became imperative. This paper gives the theoretical and numerical approaches adopted to develop a 3-D computer model of heat transfer. The implicit Spline Method was selected for the problem solver. The applicability of the model was verified using measured data on temperature distributions at several material interfaces. Then the model was used to estimate the effect of lateral heat flows. The paper also briefly reports the experimental details and presents results on model verification.

A consortium research project was initiated to determine the field performance of various thermal insulation products as applied in the exterior insulation basement system (EIBS). Initially a two-dimensional analytical tool was used to derive the thermal transmission characteristics from an array of temperature measurements monitored over a period of two years. Results immediately showed the influence of lateral heat flux between various products that differed in thermal transmission properties. Therefore, development of a three dimensional model became imperative, to resolve the order of magnitude of the lateral heat flux in the experimental set-up, and determine the actual in-situ properties of the insulation specimens. This report gives the theoretical and numerical approaches adopted to develop a three-dimensional computer model of heat transfer. The implicit Spline Method was selected for the problem solver. The applicability of the model was verified using measured data on temperature distributions at several material interfaces. Then the model was used to estimate the effect of lateral heat flows, and to determine the in-situ thermal properties of the insulation specimens. The report also records experimental details and presents validation results of the analytical approach.

IRC investigation of moisture damage in EIFS systems

Seventh Conference on Building Science and Technology: 20 March 1997, Toronto, Ontario

This paper postulates a new test for the evaluation of EIFS integrity as a more reliable approach to predict field performance. This test involves pre-conditioning of the system under simultaneous exposure to a water vapour gradient and a temperature gradient, followed by exposure to severe conditions of one-sided, uni-directional climatic cycling.

This paper presents the results of work performed to enhance understanding of water penetration and moisture characteristics of barrier Exterior Insulation Finish Systems (EIFS) clad walls. The investigation was prompted by recent failures of barrier EIFS clad walls on houses in the Wilmington, North Carolina area. The objective ws to determine the cause of the problem and gain a better understanding of water penetration and moisture transport in these systems.

To control rain ingress, the Exterior Insulation and Finish Systems (EIFS) can be constructed with one of two design principles, Presented at the Seventh Conference on Building Science and Technology, 20-21 March 1997 in Toronto, Ontario.

Aussi disponsible en français: Une étude sur les systè mes EIFS: vers de meilleures constructions

Investigations of fire hazards associated with combustible claddings and with EIFS in particular are described. The investigations also included an evaluation of standard and modified-standard fire tests, and new test methods for flame spread over combustible exterior claddings. The full-scale tests showed that most of the EIFS tested would not sustain flame spread at a distance from the ignition source. The standard and modified-standard test results did not correlate well with the full-scale test results. A new test method (Vertical Channel Test) gave indications qualitatively similar to those obtained from the full-scale tests. In 1990, in Winnipeg, Manitoba, a fire occurred in a 75 unit, 8-storey apartment building clad with EIFS. The damage to the EIFS was substantial, however, in most areas it was as expected based on experience with full-scale testing.

Aussi disponible en français: Un bâtiment rénové de l' IRC sert de banc d'essai pour les systèmes EIFS

Aussi disponible en français: Outil d'analyse des pertes thermiques amélioré en fonction des nouveaux systèmes d'isolation

Aussi disponsible en francais: Éclaircissement du Code et des systèmes d'isolants extérieurs avec enduit mince

This article deals with determination of flexural strength for the purpose of product quality assurance of expanded polystyrene (EPS) boards. Using a newly developed, inexpensive flexural strength tester (FST) and a systematic sampling plan, flexural strength of eight experimental EPS products was evaluated. TheFST was shown to yield results as precise as the standard ASTM test method. This agreement implies that sampling at specified mold locations and using the FST for in-plant testing could improve the process of quality assurance for EPS thermal insulating boards.

Methods for determining dynamic thermal response using systems identification techniques are discussed. A test using a binary multi-frequency sequence as input to determine the response of a material sample is described. Z-transfer function coeffi cients are obtained using both frequency response analysis and least squares regres sion in time domain.

There are daily reminders that every effort should be made to conserve energy, not only because of rising costs but also because of the need to control air pollution. Increased use of insulation to reduce the energy requirements of buildings is one way to achieve these ends. If designers are to design insulation systems and select appropriate materials, however, they should have a clear understanding of how insulation works. This Digest is designeed to provide some of the information required for a better understanding of insulation as a material.