A double door is exactly what it sounds like — a pair of door leaves meeting in the center, both opening from a single shared frame. The visual effect is grand: wide, symmetric, often used for main entrances, formal living room access, and balcony doors where width matters more than swing economy. uPVC double doors are essentially scaled-up French doors — the same paired-sash construction with multi-point locking on the active leaf and shoot bolts on the passive leaf. Glassterr manufactures uPVC double doors at our Pannimadai factory in widths from 4 to 8 feet. The two leaves can be equal-width or unequal — a 1.5:1 split is common where one leaf functions as the daily-use door and the other only opens occasionally.
A uPVC double door is structurally two side-hung uPVC door leaves sharing a single frame, meeting at the center with the active leaf locking onto a shoot-bolted passive leaf. The hardware is heavier than a French window because doors carry their own weight differently — door hinges, door handles, mortise locks. The active leaf carries the main lock and is operated daily. The passive leaf has top-and-bottom shoot bolts engaging the frame head and threshold, and is opened only when you want the full opening width. The seal between leaves happens via a flush astragal moulding on the passive leaf with gasket compression from the active leaf.
Equally secure if specified properly. The active leaf has a regular mortise lock (often multi-point); the passive leaf is locked into the frame top and bottom by shoot bolts. The center join is also a potential weak point and is engineered with overlap and gasket. For a properly built uPVC double door, security is on par with a quality single door of the same hardware grade.
Yes — that's how most double doors work. The active leaf is the day-to-day entry; the passive leaf is locked closed via shoot bolts and only opened when you need the full width (moving furniture in, hosting events, etc).
Slightly less in some cases, because they share a frame and head detail. For a 6ft total opening, a double door is roughly 10-15% cheaper than two 3ft single doors side by side with separate frames. The double door also looks more intentional.
Yes — fully glazed, half-glazed, or with decorative glass panels in solid leaves. For main entry doors, half-glazed (top glazed, bottom solid panel) is the most common look. For balcony doors, fully glazed is typical.
Practical maximum about 8 feet (2.4m) total — each leaf at 4 feet. Beyond that, leaf weight and operation become awkward. For openings 8-12ft, bifold systems are usually a better choice.
Related guides covering this topic from other angles — different products, applications, or contexts.
Tell us the opening width and what you're using it for — we'll design the double-door split.