Wool : master's design thesis



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Given the increasing awareness of indoor air quality (IAQ) and the direct correlation to human health, passive removal materials (PRM) have become known as a potential strategy for reducing occupant exposure to indoor air pollutants (Lu 2013). In recent studies, untreated natural wool fiber has been recognized as a PRM for removing formaldehyde, sulfur dioxide and nitrogen dioxide. These are common volatile organic compounds (VOCs) emitted from sources, such as building materials, fixtures, furnishings and cleaning supplies (Darling et al. 2012). Test chamber studies have shown that wool fiber can irreversibly remove up to 67% of these VOC’s in an interior environment (Curling et al 2012). When the toxins come in physical contact with the fiber, a chemical reaction occurs due to the amino-acid side chains within the keratin molecule. Increase in air-tight buildings has recently become a concern with the rising popularity of sustainable building practices, causing occupant exposure to these indoor air pollutants to rise (Weschler 2009). Beyond known adverse health effects, such as eye irritation and respiratory issues, formaldehyde has been designated by the International Agency for Research on Cancer (IARC) as a human carcinogen and is the leading cause for Sick Building Syndrome (SBS) (World Health Organization 2010). The interior cortex of a wool fiber is hydrophilic – highly water absorbent, and can absorb 1/3 its weight in moisture. Wool fiber has a unique wicking property that allows the fiber to absorb water vapor from the air in a regulating sense; absorbing when there is an excess moisture level and releasing the gained moisture when the surrounding atmosphere is less humid. This provides passive humidity regulation in an indoor environment, stabilizing the comfort level of 20-50% relative humidity (RH) without requiring higher air-conditioning or ventilation rates (Bingelli 2010). Wool also has excellent properties for optimizing indoor acoustics, as it absorbs acoustic energy via the friction of air being moved through the tiny spaces between fibers and reduces traveling noise and reverberation (Bingelli 2010). In an untreated, natural roving state the density of wool is ideal for acoustic control in conversational speech situations where 70dB or lower is present, such as meeting rooms, lobbies and restaurants. With the consideration of these properties, wool has the capability to improve the indoor environment quality (IEQ) and the health of occupants through the absorption of indoor air pollutants, humidity regulation and acoustic control. As Australia and the USA are among the top 3 wool producing countries, I will be working specifically with locally sourced wool from New South Wales and Texas as a basis for a sustainable IEQ intervention installation model that may be applied to future projects. The wool was obtained from local, small-scale fiber farms that implement hand processing in an effort to reduce toxins, in addition to lowering the manufacturing energy and transportation emission requirements. The local supply chain model provides increased environmental, social, economic and human health benefits to the design. Individual installations based on the vernacular wool fiber atrributes and interior climate needs will greatly increase the overall spatial environment, while also serving as an aesthetically pleasing piece of art.