The size of the shutter door needs to be measured for installation. Here is a guide for measuring the door opening for your reference: (You can add it by the way after measuring the size)
Guide for measuring shutter opening:
H- doorway height (height from the ground to the top of the doorway);
B- the width of the doorway (the distance from the left side to the right side of the doorway can generally be divided into single, double and three-person parking garages);
H- lintel height (effective height from the bottom of portal beam to ceiling. Indoor beams or longitudinal beams shall be calculated according to the distance from the ceiling to the beam);
B 1 and B2- the effective distance from the hole to the inner left and right walls;
D- the depth of the doorway (distance from the doorway to the inner wall of the garage);
Note: Effective distance means that there are no obstacles. If there is a water pipe at B 1, the effective distance refers to the distance from the door to the water pipe. If there is a cross beam or heavy beam above the lintel, the correct value of h should be the height from the top of the doorway to the cross beam or heavy beam.