Measurement description Your measurements Our example
P = Roof pitch (between 35 and 53) P   =  P  = 35
H1 mm. = Desired/required distance from parapet to floor H1 = H1 = 800
H2 mm. = Desired/required distance from railing to floor H2 = H2 =  1000
C = Distance from top frame to floor C   =  C   =  1631
X1 = Distance from floor to top of batten (in accordance with desired/required parapet height) X1 = X1 = 213
X2 = Distance from floor to top of batten (in accordance with desired/required railing height) X2 = X2 = 67
Required X value: X = X   = 213