Are cat window perches safe? Yes, if the suction cups are set up right

What actually holds a window perch up

A suction cup is not sticky. When you press it flat you push the air out from under it, and the air pressure in the room then pins the cup against the glass. Everything depends on the seal at the rim. Dust, grease, a cat hair, a ridge in the glass or a stiff, cold cup can all let air creep back in, slowly. That is why a perch can hold perfectly for three weeks and then let go on a Tuesday. The cure is a good seal at the start and a regular re-press afterward.

Which windows work, and which do not

Check the glass before you buy anything.

• Works: bare, smooth, flat glass in a window or a glass door, wide enough for the whole perch.
• Does not work: textured, frosted or patterned glass, panes divided by bars where a cup would straddle an edge, and any painted, tiled or wooden surface.
• Think twice: a sash or sliding pane that you open every day, since the perch has to move with it. A fixed pane, or a window you rarely open, is the better choice.

How to make suction cups stick

Ten minutes of preparation does more than any trick. This is the order that works.

• Clean the glass with soapy water or glass cleaner, then wipe it with rubbing alcohol and dry it with a lint-free cloth.
• Wash the cups in warm soapy water and rinse them. Warm water also softens them, which helps them seal. Shake off the drops.
• Install when the glass is not cold. Suction cup makers advise applying cups above about 40°F (5°C), because a cold cup is a stiff cup.
• Press each cup hard from the center outward until it sits flat and the air is out.
• Let the perch sit empty for a few hours, overnight if you can.
• Test it with your hand. Lean on the bed with firm, steady pressure before your cat does.

The weekly check that keeps it safe

Air finds its way under every suction cup eventually. Once a week, press each cup firmly against the glass again to push that air back out, and look for any rim that has started to lift. It takes about as long as reading this paragraph.

Every month or so, take the perch down, wash the cups and the glass, and remount it. Check more often when the weather swings between hot and cold, when the window gets strong sun, or when condensation runs down the glass, because changes in temperature and humidity loosen cups. Replace any cup that has gone stiff, cracked or out of shape.

Weight, big cats and flying leaps

Always follow the weight limit the maker publishes for your perch. For ours we have to be straight with you: the maker of The Lookout does not publish a tested weight limit, so we will not make one up. It has a stainless steel frame, two brackets and four 85 mm suction cups, and it suits an average adult cat. If your cat is large, write to us before you order and we will tell you honestly whether it is the right pick.

How your cat arrives matters as much as what they weigh. A cat stepping across from a sill or a sofa back loads the cups gently. A cat launching from the floor and landing with all four feet does not. Mount the perch where there is an easy step up.

Where to mount it

Lower is safer. A perch mounted low on the glass still delivers the view and the sun, and it turns a failed cup into a surprise rather than an injury. Keep the floor beneath it clear of anything hard or sharp. Treat the window itself as part of the setup, too. The ASPCA’s advice on falls from windows is to fit snug, sturdy screens on any window that opens, and not to rely on child safety bars, which cats can slip through. A perch beside an open, unscreened window is the one arrangement we would never recommend.

When to skip suction cups

Some homes and some cats need a different answer. If your only windows are textured or divided into small panes, if your cat is very large, or if they are elderly or unsteady and would struggle with the step up, choose a sill-mounted or screw-mounted perch, or simply park a sturdy table or shelf under the window with a blanket on it. The view is the point, not the hardware. There are more window and enrichment ideas in our guides to keeping a cat happy in a small apartment and keeping an indoor cat entertained.

What The Lookout is, exactly

For reference: a flat gray mesh bed of about 12 by 20 inches (30 by 52 cm) on a stainless steel frame. Two brackets, four 85 mm suction cups and no drilling, so it suits renters. It folds up flat when it is not in use. Unused, it can be returned within 30 days.