A brief compendium of water entry results derived from laboratory tests of various types of wall assemblies

Abstract

There is an increase in the use of hygrothermal models to complete the performance evaluation of walls assemblies, either in respect to design of new assembles or the retrofit of existing wall assemblies. To this end there are guides available in which is provided information on moisture loads to wall assemblies. This includes, for example, Criteria for Moisture-Control Design Analysis in Buildings given in ASHRAE 160, Assessment of moisture transfer by numerical simulation provided in EN 15026, and NRC’s “Guidelines for Design for Durability of the Building Envelope”. The designer of a new assembly or evaluator of an existing wall is tasked with having to determine what moisture loads to apply to the wall and where to apply this load within the assembly. Typically there is little or no information that is readily available regarding moisture loads to walls and thus the suggested hourly moisture load, as given in ASHRAE 160, is 1% by weight of the total driving rain load to the wall (i.e. kg/m2-hr). In this paper, a brief compendium of water entry test results derived from laboratory tests of various types of wall assemblies is provided from which estimates of moisture loads to different types of wall can be developed. Water entry test results are given of wood frame walls typically used in housing, but also metal-glass curtain walls and other commercial wall assemblies, where possible, in terms of driving loads to the wall.

Drainage of infiltrated rainwater in wall assemblies: Test method, experimental quantification, and recommendations

“…Based on the results obtained as discussed above, and infiltration rates obtained from laboratory studies (Lacasse et al, 2019), the subsequent tests were conducted at a flow rate of 0.057 ± 0.001 l/min for multiple entry points (a total flow rate of 0.693 ± 0.006 l/min), or a single entry point with a flow rate of 0.090 ± 0.001 l/min. When the RDWA was the primary test metric of interest, multiple entry points were applied.…”

“…It is therefore of importance to choose dosage rates based on expected infiltration rates that can be obtained by laboratory studies on watertightness testing or from field studies for which water entry in wall assemblies has been monitored. In this study flow rates of 0.057 6 0.001 l/min for multiple entry points or a total flow rate of 0.693 6 0.006 l/ min (= 2.888 6 0.025 l/min.m over a length of 240 mm or 1.925 6 0.017 l/min.m 2 for a specimen area of 0.36 m 2 ) and 0.090 6 0.001 l/min for a single entry point as maximum values based on infiltration rates obtained in laboratory studies on different wall assemblies (Lacasse et al, 2003(Lacasse et al, , 2009(Lacasse et al, , 2019Olsson, 2016aOlsson, , 2016b.…”

“…This requires detailed knowledge of the wind-driven rain load on the wall, the percentage of water infiltrating in the wall assembly, the percentage of water being retained in the assembly after drainage, and the location of the retained portion of rainwater. A considerable number of studies have reported data on the wind-driven rain load onto (Blocken and Carmeliet, 2004, 2006; Van Den Bossche et al, 2013), and the percentage of water infiltration into wall assemblies (Calle et al, 2020; Lacasse et al, 2003, 2019; Recatala et al, 2018; Recatalá et al, 2020). However, the number of studies reporting information on the percentage of water retention or on the drainage performance of wall assemblies is, in general, limited.…”

Hygrothermal Simulation of Interior Insulated Brick Wall—Perspectives on Uncertainty and Sensitivity

“…They conclude the hygrothermal SLS approach has merit, albeit not yet fully explored [60]. As another example, rain infiltration in brickveneer walls has, to some extent, been investigated and discussed in terms of modeling choices [13,24,61,62]. Similar insight is, however, limited in regard to historic masonry [61].…”

“…As another example, rain infiltration in brickveneer walls has, to some extent, been investigated and discussed in terms of modeling choices [13,24,61,62]. Similar insight is, however, limited in regard to historic masonry [61]. However, two studies should be mentioned.…”