On the market you can also find windows with a trapezoidal section of the front part of the frame, the so-called "Dutch" or "Danish". Their installation depth exceeds 100 mm and often they do not require the installation of external slopes, completely blocking the opening. Such windows are more efficient than conventional rectangular ones, but they are also more expensive.
Often the profile is additionally reinforced from the inside for strength, and this is the right move. If the profile is not reinforced, it will fall apart under its own weight much sooner, and you will have to suddenly buy a new window.
Given the characteristics of glass as a material with a certain rigidity, spatial structures like double-glazed windows are distinguished by certain size restrictions. They can be within a minimum of 300mm on one side and in an aspect ratio of 5:1. But the maximum glazing area should not exceed 3 m2 in a single-chamber package with 4 mm thick glass and 4.2 m2 with 5 mm glass thickness.
Compared to wood and aluminum, which are traditionally used for window structures, PVC is also more preferable for aesthetic reasons. It is easy to assemble from it not only rectangular structures, but almost any geometric configuration.
Choosing a PVC window seal Tightness is one of the mainof plastic windows. It is achieved by using special sealing elements that are laid around the perimeter of the doors and prevent the penetration of moisture and cold from the street and the escape of heat from the side of the house. In addition to these functions, the seal is also a good sound insulator, not inferior in terms of sound reduction to the best double-glazed windows.
But in slightly more extreme circumstances, such as severe frost or heat, as well as direct sunlight (UV), it can fail. Becoming brittle in the cold and softening in the heat, it quickly becomes unusable if the window sash is actively used. But with the doors constantly closed (or constantly ajar, in micro-ventilation mode, for example), it will last quite a long time.
Important! The reliability of the entire structure depends on the type of profile. They are made of PVC and at first glance look the same. Thermal insulation is provided by internal air chambers, and metal reinforcement guarantees strength. The higher the profile class, the greater the thickness of the outer wall.
Those. the window manufacturer must have a window conformity certificate, the profile manufacturer must have a certificate of compliance with the requirements of GOST 30673-2013 for the profile, etc.
Poor-quality elements can also provoke other problems with the operation of a double-glazed window. Sealant Sealant is responsible for a snug fit of the sash of the window structure and noise insulation, the absence of drafts. To choose a sealant for plastic windows, it is enough to know that high-quality sealing rubber or silicone is elastic, pliable, and odorless. To check the quality, you can compress the media and then release it. A good seal is easily pressed through and quickly returns to its original shape, there are no creases on it.
If you see that the glasses in the double-glazed window are not parallel to each other, you can no longer buy a window. The same applies to all kinds of seals: they should fit snugly against the glass, there should not be any gaps. Sometimes the distance bar inside is designed for three glasses, although there are only two of them in a double-glazed window - this also worsens the characteristics of the double-glazed window and reduces all heat retention by the window to zero.