Is it safe to leave a window open with a dog in an apartment?

High-rise falls involving pets are more common than most owners expect, often happening when a dog leans out to watch a bird, another dog, or a person on the street below and loses balance on a low sill. Screens designed to keep insects out are rarely strong enough to hold the weight of even a small dog pushing against them.

A window restrictor, a simple hardware fitting that limits how far a window can swing open, allows airflow while removing the fall risk entirely. For sash or sliding windows, a secondary lock that permits only a small gap works the same way. Reserve full window opening for rooms your dog cannot access unsupervised.

Get into the routine of checking window states whenever you leave a room a dog has access to, the same way you would check a stove. This becomes automatic within a couple of weeks and removes the risk entirely without needing to constantly supervise.

Puppies and toy breeds under about 5 kg are lighter and more prone to squeezing through narrow gaps that would never fit an adult medium dog, so treat any window above ground level as fully closed by default for these dogs rather than relying on a partial opening. Growth spurts also change what a young dog can reach or climb onto within a matter of weeks, so reassess window safety again once a puppy is a few months older.