Mineral fiber roof cover boards

A composite roofing structure comprising:

• a roof cover board that comprises a dried base mat comprising:
• about 30 wt % to about 70 wt % mineral wool,
• about 10 wt % to about 50 wt % perlite,
• 6.5 wt % to 15 wt % starch binder and/or latex binder,
• about 2 wt % to about 20 wt % cellulosic fiber, and
• 0.25 wt % to 2.0 wt % sizing agent,
• wherein the dried base mat has an absence of bituminous material;
• a layer of insulation;
• and
• a layer of waterproof roofing membrane;
• wherein the roof cover board is over the layer of insulation, the roofing membrane is over the roof cover board, the roof cover board is attached to the layer of insulation, and the roofing membrane is attached to the roof cover board.

A composite roofing structure comprising:

• a roof cover board that comprises a dried base mat comprising:
• about 60 wt % to about 90 wt % mineral wool,
• 0 wt % to about 10 wt % glass fiber,
• 0 wt % to about 10 wt % perlite,
• 5 wt % to 10 wt % starch binder and/or latex binder,
• 0 wt % to about 5 wt % gypsum, and
• 0.25 wt % to 2.0 wt % sizing agent,
• wherein the dried base mat has an absence of bituminous material;
• a layer of insulation;
• and
• a layer of waterproof roofing membrane;
• wherein the roof cover board is over the layer of insulation, the roofing membrane is over the roof cover board, the roof cover board is attached to the layer of insulation, and the roofing membrane is attached to the roof cover board.