Compositions and methods for reducing the impact of hard water on gypsum
board foaming are provided. The compositions include adding a foam to
water and a calcined slurry. The foam includes water, dispersed air and a
surfactant. Surfactants for use include a hydrophobic portion having an
alkyl chain length distribution of about 20% to about 60% C8 chains;
about 20% to about 60% C10 chains; about 14% to about 36% C12 chains and
about 2% to about 20% C14 chains and also having a hydrophilic portion
having about 0.2 to 3.0 ethoxy groups.