08/12/25

Sealer in PVC Windows: Unseen Guardian of Comfort

The sealing strip — an elastic gasket around the perimeter of the sash and frame — performs several critical functions that determine the comfort and energy efficiency of a window.

Key Functions

1. Air Tightness
   • prevents drafts and сквозняки;
   • stops rainwater and dust from entering.
2. Thermal Protection
   • reduces heat loss through sash‑to‑frame joints;
   • helps maintain a stable indoor temperature.
3. Noise Insulation
   • dampens sound waves that might penetrate through gaps;
   • improves acoustic comfort, especially in noisy areas.
4. Smooth Operation
   • softens the sash movement when closing;
   • eliminates slamming and squeaking noises.
5. Hardware Protection
   • reduces stress on hinges and locking mechanisms;
   • extends the service life of window components.
6. Flexibility and Adaptation
   • compensates for minor profile deformations caused by temperature changes;
   • maintains airtightness even if the sash slightly sags.

Important Notes

• A high‑quality sealing strip lasts 10–15 years but should be inspected 1–2 times a year.
• Replace it if it loses elasticity or shows mechanical damage.
• Different climatic zones require different materials (EPDM, TPE, silicone).

Without a properly functioning sealing strip, even the most expensive PVC window loses half its benefits. It’s this component that ensures a “tight seal” between the sash and the frame — and that’s what keeps your home warm, quiet, and dry.