PriMera Scientific Engineering (ISSN: 2834-2550)

Research Article

Volume 6 Issue 4

Moisture Accumulation in Residential Bathrooms: Effects on Indoor Air Quality and Ventilation in Tropical Climate

Farhana Ahmed* and Sarder Mohammad Hafijur Rahman

March 14, 2025

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Abstract

Excess moisture accumulation in residential bathrooms significantly impacts indoor air quality (IAQ) and occupant comfort, especially in tropical climates like Dhaka, where high humidity levels from activities such as showering and bathing are common. Inadequate ventilation exacerbates moisture buildup, leading to condensation, microbial growth, and structural damage. This research aims to assess moisture generation and accumulation in residential bathrooms, evaluate ventilation strategies, and propose architectural guidelines to address moisture-related issues. The study was conducted in two bathrooms in Dhaka's Wari area, characterized by hot, humid, and rainy conditions typical of tropical climates. Environmental factors such as temperature, humidity, surface temperature, and moisture accumulation were measured in both the bathroom and adjacent changing room. Ten male participants bathed under various ventilation conditions (High, Low, and Off modes), with standardized bathing styles (showering and tub bathing) and door opening durations. The results revealed that relative humidity in the bathroom reached 100% during bathing, regardless of ventilation settings. Moisture accumulation on surfaces was higher in one bathroom, attributed to floor material differences. Effective ventilation removed a higher proportion of moisture in the bathroom with better airflow, demonstrating the critical role of ventilation and material selection in moisture control. The study highlights the importance of optimizing ventilation systems and architectural design to manage moisture accumulation, improve IAQ, and reduce the risk of mold and mildew growth in tropical residential bathrooms.

Keywords: Moisture accumulation; indoor air quality (IAQ); bathroom humidity; temperature; natural ventilation; condensation; mold growth

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