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11 PolyMaster Foam Insulation and Resistance to Mold PM Mold Statement RetroFoam is naturally resistant to mold growth, and does not contain cellulose or other fiber which will sustain mold growth. RetroFoam is based on an aminoplast resin having a high nitrogen content which is toxic to most mold but is otherwise inert and non-toxic. PolyMaster R-501 foam is similar to RetroFoam, but is engineered for use in commercial block applications. PolyMaster foam aminoplast foam is toxic to most kinds of molds. Incylthane is polyurethane foam that is non-nutritive to mold. In use, polyurethane foams form a complete physical barrier between cellulose building products and moisture needed to support mold growth. Incylthane also acts as a barrier to mold spore propagation inside the walls. Caveats: Aminoplast foams contain moisture when first installed and may increase the potential for short-term mold growth in areas where high moisture conditions exist. The stated cure times (i.e. initial moisture release following installation) assume that at least one side of the wall system will be permeable to the flow of moisture vapor. Otherwise, extended cure times will result which are beyond the control of PolyMaster. The extended cure times may result in elevated moisture levels inside the wall until the curing period has completed. Aminoplast and low-density Incylthane foams are open-cell products, and will become water-logged if exposed to wet conditions over a long period of time. Limitations of Warranty:

12 PolyMaster warrants its products based on performance as an insulation material only, and does not extend to damage caused by mold or moisture. Because foam-in-place insulation is installed in a finished wall system, neither PolyMaster nor its dealers have control, or knowledge of how the wall was designed and/or constructed. Therefore PolyMaster cannot be held responsible for mold or moisture-related damages that result following initial installation. Recommendations: While there are no permanent solutions to mold, PolyMaster recommends the following best practices that should be followed: Inspect walls for indications of mold or previous water damage and determine if corrective measures have bee performed Assess inner and outer wall surfaces to verify moisture permeability prior to installation. Extended cure times will result in walls confined by impermeable inner and outer surfaces If appropriate, check humidity levels and reduce relative humidity inside the building to less than 50% during curing period Recommend increasing air exchange rates in areas where high humidity levels exist Assure that rooms where high humidity levels are common are vented Verify that a moisture barrier has been properly installed in areas where moisture is likely to flow through the wall cavity. Recommend use of fully closed-cell foams in walls where no vapor barrier exists Background: Occurrence of mold in buildings is receiving widespread attention because of its link to sick building syndrome. A growing number of law suits, primarily involving bad-faith handling of claims by insurance companies has focused public attention on damages caused by molds. A group of molds, known as toxic black molds, can cause both physical injury and property damage. Molds and fungi are prolific in the environment and include more than 70,000 species. Of these, only about a hundred pose any health concerns. Toxic Black Mold represent less than a hundred species of molds, however, they pose special concerns for the building industry because of their impact on indoor air quality and preference for wood, cellulose, and wood products as a food source. Toxic black molds were believed to be responsible for several infant deaths that occurred in Cleveland in July, 2000, and can cause variety respiratory problems in adults during long-term exposure.

13 Toxic black molds include several varieties of Stachybotrys, Alternarium, Aspergillus, Cladosporium and Pennicillium. Of these, Stachybotrys poses the most significant health hazard because of airborne toxins produced during mold growth. These molds prefer cellulose as a nutrient because of its neutral ph and low-nitrogen content. Additionally, molds require a source of moisture, usually above 50 to 60% relative humidity. Mold growth is a concern for the insulation industry because many products contain cellulose, which is a preferred nutrient for toxic black mold. Other products use water as an aid for installation, and all types of insulation affect how moisture migrates through the wall system. Since the beginning of the Energy Age in the mid 19070s, building trends have dictated tighter construction techniques to reduce heat loss from convection. These practices have resulted in lower and lower air exchange rates in buildings. Without appropriate controls, moisture and mold, the two ingredients for mold growth, can easily accumulate inside a structure to the point where adverse mold growth will occur. PolyMaster provides a variety of foam insulations that have widely different chemical and physical properties with respect to the mold problem. Foam insulation is biologically sterile because it is manufactured on-site from virgin materials, and does not contain cellulose- a preferred nutrient for mold. Aminoplast foams are unique because they have high nitrogen content, making them chemically toxic to molds and fungi. Understanding the Problem Molds propagate through the release of microscopic spores, which are carried with the air and accumulate on any exposed surfaces. Construction materials exposed to outdoor air will be contaminated with mold spores before they are installed in a house or building. There, the spores remain dormant, sometimes for long periods of time. Because mold spores are so prolific, there is no way to completely disinfect a house or building once it is built. Even if possible, mold spores would re-infect the structure over a brief period of time. The spores only become a threat when moisture levels caused by wet conditions initiate growth in areas where there is available nutrient. Most often, mold growth occurs as the result of flooding, faulty plumbing, improper water drainage, etc., and usually worsens when the moisture source persists for an extended period of time. In addition to moisture, mold needs an available nutrient to support growth. Toxic black mold prefer an organic media such as cellulose that has low nitrogen content, and a neutral ph. Cellulose is the fiber found in wood and wood products and is prevalent in residential construction. Even dusts that accumulate on non-nutritive media contain cellulose and will support mold growth, and include areas such as inside air ducts and plenums.

14 Under wet conditions insulation of any type whether used in ceilings or walls will accelerate mold growth by holding moisture next to construction materials or other media that support mold growth. Insulation can also act as a moisture sink if the moisture barrier is incorrectly applied, and the wall cannot breathe. In this situation, the properties that make an insulation material attractive (i.e. high cellular content) will also cause the material to hold moisture when it becomes wet. Dew point is another factor that needs to be understood. The dew point is defined as the combination of temperature, barometric pressure, and humidity where water changes from the vapor state to the liquid (water) state. If this occurs inside the wall when moisture flows through a wall where there is a significant difference between the indoor and outdoor temperatures, the insulation can act to retain moisture anytime the dew point temperature is reached inside the wall. Installation of a moisture barrier on the humid side of an insulated wall will prevent this from happening. The key to mold control is to control the moisture levels inside the structure. Most molds require humidity levels to be in the range of 50-60% for spores to become active. Also, mold growth usually occurs at temperatures around 60-80F, which is typical for most buildings..