ᐅ Install a wall pilaster to reinforce the window opening.

The window manufacturer wants to install a mullion strip on the interior side of our new patio doors in the new building for reinforcement. When they tried to adjust the door panels, they noticed that the window was probably not installed correctly. It continuously rubs against the bottom of the frame. The mullion strip is supposed to fix all of this. One of the patio door panels is 1.06 m (3 ft 6 in) wide and 2.12 m (7 ft) high. What does such a mullion strip look like, and does this make sense?

I am only familiar with the construction of a 'pilaster' on the exterior of buildings. It serves both aesthetic purposes and structural reinforcement of the wall.

What exactly does the window installer hope to achieve by structurally reinforcing the interior masonry?

Regards, Bauexperte

Pilasters are also installed horizontally in door panels, mainly for aesthetic purposes. In this process, metal strips are inserted into horizontal joints.
Does he want to install something like this above the patio door for reinforcement?
He should explain to you what he means.

Regards

It is likely a multi-panel balcony door, with the sash measuring 106 x 212 cm (42 x 84 inches). For cost reasons, this type of balcony door is often built with insufficient reinforcement. As a result, the entire unit can wobble when closing. The applied vertical lath is intended to strengthen the structure and reduce wobbling. What does this have to do with the sash rubbing permanently against the frame? Nothing or very little.

Typically, the design includes a rebate clearance of 4 to 12 mm (0.16 to 0.47 inches) between the frame and the sash. Additionally, the door hardware can raise the sash by about 2 mm (0.08 inches). A sash lifter should also prevent the sash from sagging. Beyond that, it is difficult to say more from a distance without further detailed knowledge of your particular case.