Building walls in new houses, renovation workers will leave a door hole. When booking a room door, accurately measure the door opening data to reduce the error as much as possible, so as to avoid unnecessary troubles in the later period. Then, how much is the size of the door standard? How to measure the door opening data is more accurate? Not in a hurry. Next, I will explain to you here and hope to help everyone. 
What is the standard size of the door ?
The size of the room door purchased, the opening method chosen by each person also affects the required size. Nowadays, in the field of decoration, the more common door sizes are: 800*2050mm, 900*2050mm, 700*2050mm, etc., but this is not necessarily on the surface. The width of the door must be installed in accordance with this size. Whether it is on the Internet or a professional construction professional, the standard surface size is the best, but it does not mean that there are no other dimensions. Each house will have different door dimensions depending on the size of the house and the architecture. 
How to measure portal data more accurately
After the doorway is designed, it is to set the door in the store. At this time, the door is usually measured to measure the data. However, in order to prevent the situation, it is best to test it yourself and reduce the error as much as possible!
1. If it is a normal rectangular doorway, as shown in the figure below, the width of the doorway and the height of the doorway must be measured three times. Then take the smallest one out of the three data. 
Measured door opening width data = door leaf width + door leaf reserved gap + door frame main board thickness + door frame fixing board thickness + door frame adjustment allowance
The width of the facade = the width of the door and the width of the door sleeve
2. If you are dealing with irregular openings, as shown in the picture, you need to use cement mortar or blockboard to correct the door opening and make a rectangle. The subsequent measurement is the same as the above method.
The size of the door leaf is deducted from the space reserved for the door and window, and the resulting size. 
When measuring the width of the door leaf, select the measurement width of multiple measurement points (at least five measurement points need to be selected) according to the distance of the inner space obtained by the horizontal measurement of the door frame, and select the smallest one from the measured data.
When measuring the height of the door leaf, it is necessary to select multiple test points from the vertical direction for measurement (again, at least 5 measurement points need to be selected), and in the measurement result, a minimum value is still selected. 
Xiao Bian concludes: For the size of the door, what is the question? Are you still in doubt? In fact, according to the structure of your own house, the size of the door hole is not the same, the method of measuring the door hole also told everyone on the measurement There should be no problem, but if there is a difference between the size of the door and the standard size, don't worry too much. The problem is not great!
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