Risk Assessment of Joint Sealing Tape in Joints between Precast Concrete Sandwich Panels Resilient to Climate Change

Abstract

Lately, a new technical solution, pre-compressed joint sealing tapes in precast concrete sandwich panel facades, has been introduced in Sweden. Although the consequences of performance failure can go far beyond the component, affecting the building, the introduction has gained little attention in terms of risk assessment in the literature and in industry. Instead, reference cases are used as verification without formal evaluation, potentially leading to serial failure. The aim of this paper was to provide guidance on how a design–build contractor should handle this new technical solution. A risk assessment framework using a design–build contractor’s perspective was applied to the case. The framework addresses new technical solutions or adaption to new conditions (e.g., climate change) with the aim of preventing serial failures. Moisture conditions within the joints were simulated using present and future climates, and probabilities of failure were assessed using the Monte Carlo method. The results of the study included identified risks of failure associated with the solution and factors influencing the probability of failure. A main issue was the exposure of the facade to driving rain but also run-off areas and imperfections in the application of the joint sealing tape. Future climate changes affect performance negatively. In conclusion, the new technical solution might be possible to use if draining potential is ensured in all detailed designs and a set of recommendations, including full-scale testing, is provided for the design–build contractor.

Pre-Compressed Foam Sealing Tapes to Seal Joints between Building Envelope Components Watertight: An Experimental Assessment

“…This means that once the water starts to penetrate the present openings or deficiencies, it may flow further inwards reducing the thermal performance of the insulation or causing premature deterioration of the underlying materials. Taking into account the results obtained in this study, the abovementioned dimensions of openings through which water can penetrate and the resulting infiltration rates, it can easily be understood that several researchers have concluded that water infiltration across the exterior barrier of a sealed joint is inevitable and that a secondary barrier and drainage possibilities should be provided, in particular when pre-compressed foam sealing tapes are applied [16][17][18]20,21,38].…”

“…It is however, acknowledged by the building industry that defects, such as adhesive cracks, will occur in the sealant over the lifespan of a building which may result in infiltration of rainwater [9][10][11][12][13]. Therefore, there is currently a gaining interest in alternative materials and approaches to seal joints watertight [14][15][16][17][18]. Additionally, as it is predicted that due to climate change the intensity and frequency of extreme weather events and the amount of wind-driven rain will increase in the Northern part of Europe, the necessity for sealing materials with high resistance to wind-driven rain also further increases [19].…”

“…All the abovementioned studies concluded that foam sealing tapes should either be applied in combination with, for example, silicone sealant or that drainage possibilities should be provided. Svensson Tengberg et al [16] also concluded that draining properties for joints using foam sealing tape should be determined. The concept of drainage and, more specifically, the use of a pressure-equalized drainage cavity is a well-known concept to increase the resistance of both walls and joints to the penetration of rainwater.…”