What affects the price?
The biggest price difference is usually the installation surface. A straightforward timber door or suitable flat panel is normally simpler than double glazing, a composite door, aluminium, a specialist panel or an external wall. Flap size, access and the condition of the door or frame can also change the work required.
| Installation type | What usually affects the cost | M25 Glazing approach |
|---|---|---|
| Suitable timber/uPVC/panel installation | Flap size, panel construction and access | From £95 for suitable straightforward jobs |
| Double glazing / glass | New made-to-measure pane or sealed unit, safety-glass specification, size and flap opening | Quoted after checking photos and measurements |
| Composite or aluminium door | Internal construction, reinforcement, panel design and cut position | Assessed before cutting |
| Wall installation | Wall thickness, construction, tunnel length and safe route | Quoted individually |
| Dog flap / larger pet door | Larger opening and heavier-duty installation | Quoted by size and surface |
For door-specific advice, see our uPVC vs composite door cat flap comparison.
Why does fitting a cat flap in double glazing cost more?
Most modern double-glazed and toughened glass doors cannot simply be drilled or cut after manufacture. The usual solution is to measure the existing glass and order a new unit with the correct opening prepared during manufacture. That means the job includes more than the fitting itself: glass measurement, manufacture and replacement all form part of the work.
For a detailed explanation, read our guide: Can you install a cat flap in double glazing?
Does the cat flap itself cost extra?
It depends on the job. Many customers already own the flap they want fitted. Standard manual flaps are usually cheaper to buy than microchip or smart models, but the installation price is driven more by the surface and opening required than by the electronics inside the flap.
How can I get an accurate quote?
For the quickest quote, send a clear photo of the whole door, window, panel or wall, a closer photo of the proposed fitting area, the flap make/model and your London postcode. If the job involves glass, a photo showing the whole pane is particularly useful.
For the installation service itself, see our Cat Flap & Dog Flap Installation London page.
Frequently asked questions
How much does cat flap installation cost in London?
M25 Glazing offers suitable straightforward installations from £95. Glass, double glazing, walls and specialist installations are quoted separately.
Can you fit a cat flap in double glazing?
Yes. A new made-to-measure glass unit with the correct opening is normally required.
Can I supply my own cat flap?
Yes. We can fit many customer-supplied models when they are compatible with the chosen surface.
Do larger dog flaps cost more?
They can. A larger opening and the construction of the door, panel, glass or wall can increase the work required.
Get a cat flap installation quote
Send us your photos, flap model and postcode for a clear quotation.