Gypsum Panel Containing Reclaimed Gypsum and a Water-Resistant Additive

A method of making a gypsum panel comprising:

• grinding a reclaimed gypsum panel and/or reclaimed gypsum panel pieces into a reclaim composition, the reclaim composition comprising reclaimed gypsum, reclaimed facing material, and a reclaimed water-resistant additive, the reclaimed gypsum panel comprising a reclaimed gypsum core and one or more facing materials, the reclaimed gypsum core comprising the reclaimed water-resistant additive, the reclaimed water-resistant additive being present in a portion of the reclaimed gypsum core adjacent at least one facing material in a higher concentration than the center of the thickness of the reclaimed gypsum core;
• separating at least a portion of the reclaimed facing material of the reclaim composition from the reclaimed gypsum to form a second reclaim composition, the second reclaim composition comprising the reclaimed gypsum in an amount of about 70 wt. % or more;
• providing a first facing material;
• depositing a gypsum slurry comprising water and the second reclaim composition, the second reclaim composition being optionally calcined;
• and
• providing a second facing material on the gypsum slurry.