The main function of the sealant, which is a mandatory part of PVC windows, is to protect the room from the cold to keep the heat inside the room. The seal serves as an airtight seal, it also protects rooms from moisture, dust, and street noise. A seal is attached between the window sash and the frame.
Modern seals can be made of rubber, silicone, polymers, modified PVC. Black rubber stamps are the most popular. Silicone: lightweight, they are generally used in severe climates, as they can retain their properties in severe frosts.

How do you know when it is time to change the stamps?
Manufacturers typically offer a five to ten-year warranty on these parts. If you start to feel like you are leaking out of the windows, on the windowsill, even if the window is closed all day, a layer of dust forms, it means that something is wrong with the seals. Checking the tightness is simple: insert a sheet of paper into the open sheet, close the window and pull the sheet out. If it came out very easily, without resistance, then the seal can no longer cope with its functions.
There can be several reasons for the wear of the seals at the same time: long service life, severe weather, exposure to ultraviolet rays. In any case, the dry cracked and thinned PVC window gasket must be replaced because the comfort and warmth in your home depend on it.

Manufacturers advise contacting specialists and service departments to replace seals. The price of such a service is on average 150 rubles per linear meter. It is not very expensive, we agree, but if you want to save money, you can try to do it all yourself. To do this, you will first need to purchase a new stamp. They are selected taking into account the manufacturer of the plastic window, as well as the size of the old seals. New ones cost about 20-25 rubles per linear meter. You can buy in the construction market or in companies engaged in the installation of plastic windows.
The first step is to remove the old seal. Find where to hook it, for example with a not too sharp knife, a small putty knife, and pull it out of the slot. The seal location is carefully cleaned to clean it of dirt and dust.

Then one end of the stamp is inserted into the groove and its pad should be completely drowned out. Rubber glue is applied to the corners to further secure the seal. No glue is required on the entire length.
Then we pass with our finger or an improvised tool, for example, a screwdriver, but better still with a spatula, going through the entire tape and inserting it into the groove around the entire perimeter, without tension or compression. The kantik remains outside, it will be responsible for the tightness of the window. Excess tape is cut off, glue should also be applied at the joint joint, fixed.
It is quite simple. Another thing is when it comes to the seal between the glass unit and the frame, in which case you have to remove the plastic glass beads, remove the liners, remove the glass unit and then put everything back. This is already quite a complicated process. However, internal seals wear less often and last longer.

After replacing the seals, also check the fit of the leaves, make sure that now the window is tightly closed, nothing interferes, everything is done correctly
To make plastic window seals last longer, experts advise washing them at least once every six months with soap and water and cleaning them with silicone grease (sold in auto accessories department stores). This will help them maintain elasticity for a long time