Cleanliness and comfort are basic requirements of freestall design, construction and maintenance. Cleanliness—a clean and dry stall bed—results in cleaner cows and udders. Comfort—a comfortable bed, appropriate lunge space and roomy dimensions—helps to assure that the cow will choose a freestall when she lies down. In simplest terms, the purpose of a freestall is to reduce exposure of teat ends to mastitis causing organisms when a cow lies down. With effective freestalls, cows lie down 10-14 hours per day.

Swollen hocks and knees result from a bed lacking cushion (concrete, a rubber mat, compacted earth). Also, mounds, lump or holes in the bed reduce comfort, besides causing problems for the rising cow. Difficulty in rising and lack of comfort both discourage freestall use.

Two methods have emerged as candidates for a freestall base and bedding: i) mattresses with dry bedding on top and ii) a deep layer of sand. For cow comfort, a bed of loose sand can be considered the gold standard. The only logical reason for not using sand relates to the difficulty sand adds to the manure system or the availability of high quality sand. Detailed planning of the manure system—including selection of handling equipment, storage type and land application method—is essential.

Loose sand conforms to the shape of body components—knees, hocks, etc.—spreading the cow's weight over a larger area.A larger contact area reduces pressure on projecting bones and body parts when she is lying down.

Increased contact area protects the knees also. A cow lunges forward on her knees as she rises from a lying position, transferring her body weight forward so she can rise more easily on her hindquarters. During the lunge, the weight transfer process increases the downward force on each knee from 350 lb. (about 1/4 of the cow's weight) to 500 lb or more—on each knee! Sand conforms to the shape of the knee, increasing the area over
which this downward weight of the cow is distributed. This reduces the potential for injury to the knee.

Loose sand consistently distributes the downward weight better than any other material or combination currently in use. Thus, loose sand represents the standard of comparison when evaluating stall beds of various materials for their cushioning effect.

Good footing in a freestall helps a cow to lie down and rise easily. In this case, "footing" means not only reducing the tendency to slip, but allowing the cow to embed her foot in the surface to provide good leverage. When a cow can rise more confidently, the tendency to rock back-and-forth is lessened, rising time is reduced trauma to knees, ankles, etc. is kept to a minimum. Again, the shifting nature of the sand is a benefit, providing excellent "footing". Beds of other materials must be equivalent.