15/11/25

PVC Window Construction: Key Components

A PVC window is a complex system of interconnected elements. The main parts are:

1. Profile — the window’s frame and sashes made of polyvinyl chloride with metal reinforcement. It ensures structural strength, geometric stability, and thermal insulation. The number of chambers (3–6 or more) affects energy efficiency.
2. Insulating glass unit (IGU) — the translucent part consisting of 2–3 panes with air or gas‑filled gaps. It controls light transmission, thermal insulation, and soundproofing. May include energy‑saving, tempered, or noise‑reducing glass.
3. Hardware — mechanisms for opening and closing: hinges, handles, locks, locking elements, and micro‑ventilation systems. Determines user convenience and window lifespan.
4. Seals — elastic strips (rubber, silicone) along the sash and frame perimeter. Ensure airtightness, protect against drafts, moisture, and noise. Usually 2–3 sealing lines are used.
5. Mullion — a vertical or horizontal partition inside the window. Separates sashes or glass units, reinforces the structure.
6. Drip cap (external sill) — a metal or PVC profile below the window. Directs water away, protects the installation joint from moisture.
7. Internal sill — a profile beneath the frame. May have a multi‑chamber structure for extra thermal insulation. Often used as a shelf.
8. Drainage system — holes in the profile to remove condensation. Hidden by decorative caps.
9. Window reveals — decorative panels on the sides of the window opening (not part of the window unit, but essential for installation).

Each component affects airtightness, heat retention, and durability. Proper installation integrates all parts into a single, reliable system.