To remove mold from an attic, seal and dry the affected area, remove any mold-covered material, use an appropriate cleaning solution, use a dry-ice gun, and sand or wire-brush the affected areas. Once the mold has been removed, coat all of the attic's surfaces with an antimicrobial or mold-inhibiting material, and ensure the attic is properly ventilated.
The first step in removing mold is to thoroughly dry it. Active mold spores are spread when disturbed, which increases the fungus' coverage area. Sealing all windows and vents and then employing heaters, fans and a dehumidifier speeds the drying process. Always wear protective clothing, gloves, eye protection and a breathing mask.
Remove every item possible from the attic to access as much of the surface area as possible. Some sources say to remove and replace any plywood, sheetrock or other materials that are contaminated with mold. If this is not feasible, sanding the surfaces is an option. Cover the floor under the areas to be sanded with polyethylene sheeting. After sanding, vacuum the sheeting with a cleaner that has a HEPA filter, and then discard the sheeting.
White vinegar or hydrogen peroxide are safe and non-toxic cleaners that kill mold. Mix 1 teaspoon of vinegar with each cup of water, or combine one part hydrogen peroxide with two parts water for effective mold-cleaning solutions. Spray on the chosen solution, and let it sit for about one hour. Scrub off the solution using a wire brush. Use a plastic sheet to catch and remove the mold. Blasting off the mold with dry-ice pellets works as well.