Zero Fungal Contamination in a 14-Day Tropical Chamber Test

In tropical, subtropical, and high-humidity climates, fungal growth on building surfaces is a durability and indoor-air-quality concern with real maintenance cost. Surfaces finished with non-antifungal coatings can show visible contamination within weeks. The standard is straightforward: lab-confirmed resistance to fungal colonization under conditions designed to maximize growth.

The tropical chamber maintains continuous elevated temperature and humidity while recirculating a diverse inoculum of fungal spores - Aspergillus niger, Penicillium, Cladosporium, Trichoderma and more. Conditions: 32 °C, 98% relative humidity, 14 days continuous. Each product was applied to cement board in two coats and cured before exposure, then scored 0 (no growth) to 5 (over 75% surface) on days 1, 2, 4, 8, 11 and 14.

All four formulations - Natural Sealer (Spec A, Spec B) and Bio Block (Spec A, Spec B) - scored 0, zero fungal contamination, across every inspection point through day 14, confirmed by photographic documentation.

The chamber held over a dozen aggressive fungal species under near-saturation humidity - deliberately harsher than virtually any real-world installation. The complete absence of contamination is strong evidence of antifungal efficacy.

• Exterior facades in coastal and tropical climates
• Bathrooms, laundries, and other high-humidity interiors
• Cementitious surfaces in commercial, residential, and institutional construction
• Building envelopes needing long intervals between maintenance

See how our coatings perform in other independent tests on the Case Studies page.