Fitting a Cat Flap in a Glass Door — What You Need to Know

Can you put a cat flap in a glass door?

Yes — and it's one of the most popular requests we get at Maidenhead Glazing Services. Whether you have a uPVC French door, a patio slider, or a glazed back door, a cat flap can be fitted cleanly and safely into the glass panel.

There is, however, an important catch: you cannot cut a hole into existing toughened or laminated safety glass. Modern double-glazed units are manufactured from toughened safety glass to British Standards, and once toughened, any attempt to drill or cut the pane will cause it to shatter completely.

How we do it

The safe, correct method is to replace the existing pane with a brand new, purpose-made toughened glass unit that is manufactured complete with the correct sized opening for your chosen cat flap. The process is straightforward:

1. Site visit and measure — we come to you, measure the door frame, and note the exact cut-out size for your cat flap make and model.
2. New glass ordered — the replacement toughened pane is made to order with the hole pre-cut.
3. Fit and install — we return to fit the new glass and install your cat flap, leaving everything clean, secure, and ready for your pet.

Because we only replace the glass — not the whole door — it's far more affordable than you might think, and the whole job is typically completed across two short visits.

Which cat flaps can be fitted?

We work with all the popular brands and models, including:

• SureFlap and Sure Petcare microchip cat flaps
• Cat Mate pet doors
• PetSafe and Staywell models
• Standard and large sizes
• Dog flaps and small pet doors on request

If you have a microchip-enabled cat flap that needs a specific cut-out, just let us know the make and model when you call and we'll make sure the new glass is manufactured to the exact specification.

A tip for tenants

If you rent your property, ask us to keep the original glass safe. When you move out, we can easily swap the original pane back in — so your cat flap investment doesn't have to be lost.

Book your cat flap installation

We cover Maidenhead, Marlow, Henley, Ascot, Slough, and the wider Berkshire and Thames Valley area. Give us a call on 01628 303060 for a free, no-obligation quote, or use our contact form and we'll get straight back to you.