PLASTER BOARDS AND METHODS FOR MAKING THEM

1 - 19 . (canceled)

20 . A method of manufacturing a plaster board having

a major plane,

a first major surface and an opposing second major surface, each lying parallel to the major plane, and

a first edge extending from the first major surface to the second major surface, and a second edge extending from the first major surface to the second major surface,

the plaster board comprising:

a first panel disposed at the first major surface of the plaster board, and lying parallel to the major plane the first panel having an outer surface forming the first major surface of the plaster board, an opposing inner surface, a first edge disposed at the first edge of the plaster board, a second edge disposed at the second edge of the plaster board, and a center between the first edge and the second edge;

a second panel disposed at the second major surface of the plaster board and lying parallel to the major plane, the second panel having an outer surface forming the second major surface of the plaster board, an opposing inner surface, a first edge disposed at the first edge of the plaster board, a second edge disposed at the second edge of the plaster board, and a center between the first edge and the second edge; and

a layer of hardened plaster material disposed between the first panel and the second panel, wherein the layer of hardened plaster material comprises

a first region disposed proximate the first edge of the plaster board, the first region having a first density, and

a second region having a second density,

wherein

the first density is at least 110% of the second density, and

the second region is disposed laterally between the first region and the second edge of the plaster board along a plane parallel to the major plane,

the method comprising:

applying a first plaster slurry line to a top surface of a first panel material proximate a first edge of the first panel material;

applying a second plaster slurry line to the top surface of the first panel material between the first plaster slurry line and a second edge of the first panel material, wherein the second plaster slurry line has a lower density than the first plaster slurry line; and

applying a second panel material to a top surface of the second plaster slurry line,

wherein the first plaster slurry line forms a portion of the layer of hardened plaster material having the first density, and the second plaster slurry line forms a portion of the layer of hardened plaster material having the second density.

21 . The method of claim 20 , further comprising bending the first panel material to form a first edge channel proximate the first edge of the first panel material, wherein applying the first plaster slurry line comprises applying the first plaster slurry line into the first edge channel.

22 . The method of claim 20 , further comprising bending the first panel material to form a center channel between the first edge and the second edge of the first panel material, wherein applying the second plaster slurry line comprises applying the second plaster slurry line into the center channel.

23 . The method of claim 20 , further comprising foaming a slurry mixture to form a foamed slurry mixture, wherein applying the second plaster slurry line comprises applying the foamed slurry mixture.

24 . The method of claim 23 , wherein applying the first plaster slurry line comprises applying the slurry mixture prior to foaming.

25 . The method of claim 20 , further comprising smoothing the first plaster slurry line prior to applying the third plaster slurry line.

26 . The method of claim 20 , wherein the density of the first plaster slurry line is at least 120% of the density of the second plaster slurry line.

27 . The method of claim 20 , wherein the density of the first plaster slurry line is at least 140% of the density of the second plaster slurry line.

28 . The method of claim 20 , wherein the density of the first plaster slurry line is no more than 300% of the density of the third plaster slurry line.

29 . The method of claim 20 , wherein the layer of hardened plaster material further comprises

a third region disposed proximate the second edge of the plaster board, the third region having a third density that is at least 110% of the second density,

and wherein the method further comprises

applying a third plaster slurry line to the top surface of the first panel material proximate the second edge of the plaster board, the second plaster slurry line having a lower density than the third plaster slurry line.

30 . The method of claim 29 , wherein the density of the third plaster slurry line is at least 120% of the density of the second plaster slurry line.

31 . The method of claim 29 , wherein the density of the third plaster slurry line is at least 140% of the density of the second plaster slurry line.

32 . The method of claim 29 , wherein the third density is substantially equal to the first density.

33 . The method of claim 29 , wherein the first density and the third density are each at least 130% of the second density.

34 . The method of claim 20 , wherein the second portion having the second density extends from the first panel to the second panel.

35 . The method of claim 20 , wherein the second region lies in a same plane parallel to the major plane as the first region.

36 . The method of claim 20 , wherein the hardened plaster material has a density substantially equal to the second density proximate the center of the first panel, proximate the center of the second panel, and halfway between the center of the first panel and the center of the second panel.

37 . The method of claim 20 , wherein the plaster board has a dry weight of less than 450 lb/MSF per ⅛″ of thickness.

38 . The method of claim 37 , wherein the plaster board has a nail pull of at least 75 lbf proximate the first edge thereof.

39 . The method of claim 20 , wherein the plaster board has a nail pull of at least 75 lbf proximate the first edge thereof.