The Aspect of Using ACP Building Envelope Material for Energy Efficiency Actually Spoils the Aesthetics Because of “ACP Drooling”

Abstract

Building facades or envelopes play an important role in supporting the realization of energy-efficient green buildings. Apart from being a protective element, the facade also functions to regulate natural lighting, ventilation, and reduce exposure to heat radiation. Aluminum Composite Panel (ACP) is one of the most popular facade materials used because it is lightweight, durable, and flexible in design. However, in the context of sustainability, there is an aesthetic issue referred to as the “ACP drooling” phenomenon - the appearance of vertical stains due to dust adhering to the sealant and being carried away by rainwater. This phenomenon reduces the visual quality of the building and is one of the reasons for the low interest in using ACP in façade retrofit projects for green buildings, especially in tropical regions with high pollution levels. This research aims to analyze the role of ACP-based facades in supporting building energy efficiency as well as evaluating the factors causing the appearance of “drooling” stains. The research methods included field observation, visual documentation, as well as a technical review of the panel connection design, installation angle, and sealant quality. The results of the analysis showed that the main problems stemmed from the non-waterproof joint detail design, inappropriate sealant selection, and non-optimal panel slope. This research recommends improving the quality of detail design, using sealants with pollution-resistant specifications, and periodic maintenance systems to maintain the aesthetic and functional performance of ACP. With the right approach, ACP facades still have great potential as green building envelope elements that support sustainable energy efficiency.