For many cat owners, a cat flap is not a luxury but a necessity. It allows pets the freedom to come and go, reduces interruptions during the day and night, and helps maintain a calm household. However, if your home has modern double glazing, you may be wondering whether fitting a cat flap is even possible.
The short answer is yes, a cat flap can be fitted into double glazing, but it must be done correctly. This is not a simple case of cutting a hole into the existing glass. In fact, attempting to do so would almost certainly damage the window beyond repair. Below, we explain how cat flaps are safely installed into double glazed units, what is involved in the process, and why professional glass replacement is essential.
A common misconception is that a cat flap can be cut directly into an existing double glazed window or door. This is unfortunately not possible.
Double glazing is made up of two panes of glass that are sealed together as a single unit. Between those panes is an insulating layer of air or gas which is crucial to the window’s performance. Once that seal is broken, the unit immediately loses its insulation, becomes vulnerable to moisture, and will begin to mist or fail.
Cutting into an existing unit would also compromise the strength of the glass. Double glazed panels are toughened or laminated for safety, meaning they shatter rather than crack when damaged. For this reason, any reputable glazing repairs specialist will always advise replacement rather than alteration.
A common misconception is that a cat flap can be cut directly into an existing double glazed window or door. This is unfortunately not possible.
Double glazing is made up of two panes of glass that are sealed together as a single unit. Between those panes is an insulating layer of air or gas which is crucial to the window’s performance. Once that seal is broken, the unit immediately loses its insulation, becomes vulnerable to moisture, and will begin to mist or fail.
Cutting into an existing unit would also compromise the strength of the glass. Double glazed panels are toughened or laminated for safety, meaning they shatter rather than crack when damaged. For this reason, any reputable glazing repairs specialist will always advise replacement rather than alteration.
The correct and safe method of installing a cat flap involves replacing the glass sealed unit entirely.
A brand new double glazed unit is manufactured to your exact measurements, with a precision cut hole already formed in the glass. This ensures the integrity of the seal is maintained and the window continues to perform as it should.
Once the new unit is ready, the existing glass is carefully removed and replaced with the new panel. The cat flap is then fitted securely into the pre cut opening. When done correctly, the finished result looks neat, professional, and functions exactly as intended.
This process applies whether the cat flap is being installed into a window, patio door, or uPVC door panel.
When installed correctly, a cat flap will not negatively affect insulation or security.
Because the new glass sealed unit is manufactured specifically for the purpose, it retains the same thermal efficiency as the original. Modern cat flaps also include draught proofing, locking mechanisms, and microchip access to prevent unwanted animals from entering your home.
The key factor is professional installation. Poorly fitted flaps or unsealed glass can lead to heat loss, draughts, and long term damage.
Cat flaps can be fitted into a wide range of glazed areas, including windows, French doors, and patio doors. However, not all installations are identical.
In some cases, door alignment may need to be checked following glass replacement. Services such as heel and toe windows or toe and heel door adjustments ensure that frames remain square and operate smoothly after new glass is installed.
These small but important adjustments are part of comprehensive glazing repairs and window repair services, ensuring your doors and windows continue to open, close, and lock correctly.
The cost of fitting a cat flap into double glazing varies depending on several factors. These include the size of the glass, the type of unit required, and the style of cat flap chosen.
As a general guide, the price includes manufacturing a new sealed unit, removing the existing glass, installing the replacement, and fitting the cat flap. While this is more involved than a standard installation, it is significantly more cost effective than full window replacement.
In most cases, the process is completed within a short timeframe. Once the new unit has been manufactured, installation is usually completed in a single visit.
If you are considering fitting a cat flap into your double glazing, expert advice is essential. RPS Double Glazing Repairs offers free quotes, honest guidance, and same day or emergency double glazing repairs where required.
Whether you need glass replacement, glazing repairs, window repair, or professional installation, contact RPS Double Glazing Repairs today to discuss your options and arrange a no obligation quotation.