# HOW TO DRAW A SPIRAL STAIRCASE IN PARALLEL PERSPECTIVE (continued 5)

Figure nº 29:

For better understanding of the raising of the spiral staircase steps, examine the process used to raise steps 1 and 3. Considering that step 1 is frontal, it was raised on the box front wall. Step 3 was constructed on the lateral wall.

See in Figure nº 27 the raising of all staircase steps.

 Figure nº 30 shows the construction of a door ajar. See how it was constructed: 1 — Calculate the door width on the width measurement line; transfer this width to the place of its construction by the vanishing point. 2 — The same measurement is found at the side of the door opening. 3 — Prolong line a, b, that goes from the door post up to the vanishing point and find point c. The distance between points c and e has the same dimension of the door opening. 4 — Construct the angle of the door opening. 5 — Select any point of this angle. See point d. From there to point e, sketch a straight line. Prolong this straight line up to the horizon and locate the vanishing point f. 6 — Sketch a line from point g to point f. Prolong this line until crossing with the vertical line referring to the door height. 7 — Calculate the door thickness and sketch a line parallel to the door vertical line.