Method for producing an inorganic foam structure for use as a durable acoustical panel

A process for creating acoustical ceiling panels comprising the steps of:

• dry mixing cement, and fibers to create a dry mix;
• aqueous mixing water and surfactant to create a diluted surfactant solution;
• combining and mixing the diluted surfactant solution, air and dry mix to create a foamed cementitious material;
• and
• drying the foamed cementitious material to form an absorbent porous panel having a density between about 10 and 40 lb/ft3, a Hess rake finger scratch test result of at least 12, a Noise Reduction Coefficient of at least 0.5, and a sag test result of less than 0.15 inches at 90% RH.

A process for creating an acoustically absorbent porous panel comprising the steps of:

• dispensing and conveying dry cement
• dispensing and conveying dry fibrous material
• aqueous mixing water, surfactant and air to create a foam;
• combining and mixing the foam and dry ingredients to form a foamed cementitious material comprising on a wet basis about 53% to about 68% by weight cement, about 17% to about 48% by weight water, about 0.05% to about 5% by weight fibers, and about 0.01% to about 10% by weight surfactant;
• and
• drying the foamed cementitious material.