Bespoke Glass

Pet Flaps in Glass and Doors: Your Options

18 July 2025 · 4 min read

Yes — you can fit a cat or dog flap into glass. Here's how it's done without compromising the window.

Fitting flaps into glass

A cat or dog flap can be fitted neatly into a double-glazed unit or a glazed door. Rather than cutting your existing sealed unit (which is not possible once toughened), a glazier makes a new sealed unit with the flap aperture built in, then swaps it into your existing frame.

The result is a tidy, properly sealed installation that keeps the window's insulation intact.

Choosing the right flap

Flaps come in several sizes for different pets, and many now include microchip recognition so only your pet can enter, keeping strays out. Draught-excluding and lockable models help with insulation and security. We can advise on the best flap for your pet and door.

The flap colour and style can be matched to suit the door or window.

A clean, sealed installation

Because the flap is built into a purpose-made unit, there are no bodged holes or lost insulation. We measure, make the new unit with the flap fitted, and install it — usually a quick job once the unit is ready.

Contact us to arrange a pet flap fitted into glass or a glazed door.

Related Services We Offer

Need a Glazier?

Free written quotes, no call-out fee, and a workmanship guarantee on every job — anywhere in the UK.