A Winter Shelter for Outdoor Cats

A Winter Shelter for Outdoor Cats

Cat Highways · Bonus · sizuriatto.com/go/cat-shelter

If there are outdoor cats near you, community cats looked after by a neighbor or a trap-neuter-return group, a small shelter can get one through a cold night. It is an afternoon's work.

The size: small means warm

Alley Cat Allies, a US charity that works with community cats, suggests a shelter about 2 × 3 ft (61 × 91 cm) and at least 18 in (46 cm) high: big enough for three to five cats to huddle. That is 3 × 2 × 1.5 = 9 cubic feet, about 0.25 m³.

Why not bigger? The only heater in the box is the cats, and heat leaks out through the walls, so the less wall there is, the warmer the inside stays.

The bigger box holds 2.67 times the air and loses heat through 1.93 times the wall, with the same cats inside to warm it. Small means warm.

The details that matter

• A door 6 to 8 in (15 to 20 cm) wide: big enough for a cat, small enough to keep larger animals out. Face it away from the wind, or put a baffle (a short inside wall) behind it.
• Straw, not hay. Straw stays dry and lets the cats burrow. Hay soaks up water and goes moldy, and so do blankets and towels, which then chill the cat instead of warming it.
• Off the ground, on a pallet or a couple of bricks, so water stays out and the cold ground does not draw the heat away.
• Somewhere quiet, away from traffic and footpaths, in a dark or sheltered spot.

The cheapest version is two plastic storage tubs, one inside the other, with straw packed between them, a foam board under the inner tub, and a door cut through both. Alley Cat Allies publishes step-by-step plans; if a local group looks after the cats near you, they will know what works in your climate, and they may well want your shelter.

Source: Alley Cat Allies, “Providing Shelter” and their outdoor cat shelter plans (checked November 2026). From the bonus page of Cat Highways; free to print and pass on.