Aluminum alloy is about 25cm. Plastic steel is about 15cm, such as hole 1500* 1500, doors and windows 1450* 1450.
In general, 15~20 should be reserved on each side of the window opening. After the window is installed, it should be treated along the mouth with heat preservation. The specification is: the window design should be consistent with the drawing size, and the door should be scaled to about 15mm on each side according to the drawing size, that is, the plastering thickness.
Doors and windows openings are planned when the drawings are designed, and the construction party should reserve openings according to the design specifications of the drawings. For example, the size of the upper window in the drawing is 1200* 1500, and the reserved hole must be 1250* 1550, and the size should be appropriately increased to facilitate installation and construction.
Extended data:
Metal doors and windows, plastic doors and windows installation must first build by laying bricks or stones a wall to set aside the hole, and then put the doors and windows into the hole. It is forbidden to install the hole while building walls or installing doors and windows first. This is due to the following two reasons:
First, metal doors and windows and plastic doors and windows are different from doors and windows, except that solid steel doors and windows are hollow, and the materials of doors and windows are thin, such as hammering or squeezing, which is easy to cause local bending damage;
Second, there are protective decorative films or antirust coatings on the surfaces of metal doors and windows. If the protective decorative film is worn, it is difficult to repair it; If the antirust coating is not repaired in time after wear, it will also lose its antirust effect;
Therefore, in order to ensure the installation quality and use effect of doors and windows, doors and windows must be installed after the hole is built. Metal doors and windows are often connected with the wall by shooting nails, expanding bolts or welding methods.
Nail must have a solid wall, and the wall must be built first. When the doors and windows are installed, the wall is already strong. If the wall is built later, it can't bear the impact of nailing. When installing expansion bolts, it is necessary to drill holes in solid walls. If the wall is built later, you can't make holes. Welding needs to embed the connecting steel plate in the wall in advance. If the wall is built later, it is more difficult to embed the steel plate.
Baidu Encyclopedia-General Rules for Civil Architectural Design