Installing Pet Flaps Into French Doors/Glass

If you’re thinking about having a pet flap fitted into double glazing, it’s really important not to attempt the job yourself. A cat flap can’t be cut into your existing double‑glazed unit—doing so would cause the glass to shatter instantly, as all door and window glass must legally be toughened safety glass. Instead, a brand‑new sealed unit has to be made, and the hole for the flap is cut into the glass during the manufacturing process. The glass is then toughened in a large furnace before the two panes are assembled into the finished unit.

If you were to try cutting into the existing glass, it would break into thousands of small pieces, just like a car window does when it’s smashed. That’s why this type of installation should always be handled professionally.

At Double Glazing Repairs, I specialise in all types of pet flap installations and only use trusted manufacturers who produce sealed units to the highest standards. If you’re considering a pet flap in double glazing, leave the hard work to a professional—get in touch and I’ll be happy to guide you through the process.