Smad 1 = 3/3
Smad 2 = 3/3 + 3/3 = 6/3
Overlap 1/3 6/3 - 1/3 = 5/3
5/3 - length Smad on the roof
Example: Length of the alleged lambrequin - 2.0 m
(2,00:5)X3=1.20 m - length one Smad
Smad 3 3/3 + 3/3 3/3 = 9/3
2/3 overlap
9/3 - 2/3 = 7/3 - length Smad on the roof
Example: Length of intended pelmet 3.0 m (3,00:7)X3=1,286 m - length one Smad 
7 Smad
3/3 x 7 = 21/3
6/3 overlap
Example: Length of the alleged lambrequin - 4.0 m
21/3 - 6/3 = 15/3 - length Smad on the roof
(4,00:15)X3=0.80 m
0,80 - length one Smad
Mechanical Smad - is a peculiar constructor. By placing different parts, we can obtain various models of valances.
mounting tapes primatives along the lines a - b - C - d - e - f - g - h
going to build in stretches a - b; C - g; d - e; W - W
not going for segments b - C; d - d; e - f; it's the middle of Smad