Orthopaedic Memory Foam Mat

Almost every "orthopaedic" dog bed on the market is a sack of shredded foam. It feels supportive in the shop and compresses into a flat, lumpy mat within two months. This is a single slab of 45kg/m³ memory foam, 10cm deep, which is the density used in human mattress toppers and does not bottom out under a 40kg dog.

Flat rather than bolstered is deliberate. Older dogs and dogs with hip or elbow arthritis sleep stretched out, and a raised rim forces a curl that some of them can no longer comfortably hold. If your dog likes to press against something, the donut bed is the better buy. This one is for the dogs that sprawl.

There are two layers of cover. A waterproof inner zips around the foam and copes with the accidents that come with age or a long anaesthetic recovery, and the outer cover unzips and washes at 40°C. That two-layer arrangement is what stops one bad night ending the bed's life.

Give it a day. Memory foam is temperature-sensitive and ships compressed, so it arrives firm and feels wrong; it reaches full loft in about 24 hours in a warm room. Do not put it in a tumble dryer, and do not leave the cover off in direct sunlight. UV breaks the foam down faster than a dog does.