Cat Flaps In Lewisham

Lewisham’s housing stock includes a large number of properties with replacement double glazing fitted over the last two decades, particularly in areas like Catford, Grove Park, and Lee Green. Many homeowners assume a cat flap can simply be cut into an existing sealed unit, but doing so breaks the hermetic seal that holds the inert gas between the panes. Once that seal is gone, the unit will mist from the inside and the thermal performance drops significantly. A professional cat flap glazier in Lewisham will always replace the sealed unit rather than attempt to cut into an existing one, protecting both your window and your home’s energy efficiency.

An ill-fitting flap creates additional problems beyond the glass itself. Draughts, water penetration, and reduced security are all real risks when a pet door installation is not done correctly. Fitting a cat flap in glass requires precise measurement, the right glass-cutting equipment, and proper sealing around the flap housing. For period properties in Lewisham, particularly the late-Victorian terraces that are common around Hither Green and Catford, maintaining the integrity of the window frame during installation matters too. Montrose Glass carries out all Window Glazing work to a consistent standard, and cat flap installations are treated with the same level of care as any other glazing job. Poorly fitted flaps can also void a window warranty, so using a qualified glazier protects your investment in the long term.