From time to time, fabric upholstered items can become mildewy from being stored or used in a moist environment. Fortunately, you can clean mildew from items such as a fabric upholstered chair fairly easily if you have the right tools. Best of all, cleaning mildew from fabric upholstery is not expensive or time consuming.
Take chairs that have mildew outside before you start to clean them. It is best to clean mold and mildew in well-ventilated areas. If you cannot take your chairs outside, cover the area you are working with in old newspaper, and use a window or exhaust fan to vent the air.
Brush away any loose mold and mildew from the surface of the chair with a hand broom. If you are inside, make sure to carefully remove the newspaper below the chairs when you are finished cleaning so you do not get the spores on anything else.
Vacuum the upholstered chair with a hand vacuum or a vacuum with a hand attachment. This will help remove any mildew growth from below the surface of the fabric.
Mix 1 cup of water and 1 cup of denatured alcohol in a mixing bowl. Submerge a clean, soft cloth into the mixing bowl. Wring the cloth out, and use it to wipe the surface of the upholstery clean.
Dry the item in the sun before bringing it back into the house. You may also use a fan to dry the upholstered chair. Make sure it is dried completely, so as not to promote new mildew growth.
If you believe that mildew has grown in the padding of a chair it should be cleaned professionally.