The Whelping Box   Here are some very desirable requirements for an adequate whelping box. It needs 4 sides that are high enough to keep 3 week old puppies from climbing out, but low enough that the dam can jump out easily when she needs to. Having the sides about 12" high is a good height. Puppies are very susceptible to drafts, so the 12" solid sides are very important. It needs to have a washable surface. Ours are built from Melamine. This is heavier than plywood, but very easy to clean Painted Plywood will be alright, but you may get slivers when you clean it, and it does absorb odours. Melamine does not. It must be big enough to allow the mother dog to stretch out completely, so the size is dependent on the breed of dog. Ours, for our 30 lb. Kerry Blues are 4' x 4'. Here is ours, standing on it's end for better viewing. You should install a 'pig rail' around at least 3 sides of the box, 3" from the sidewall of the box. You can make it from wooden doweling cut to fit. We use aluminum tubing because the pups can't chew on it. The pig rail prevents the mother from lying on a puppy, since it prevents her back from actually touching the sidewall, thus leaving a space for a puppy to safely crawl into. It is very convenient to build the box so that the 4th side is removable. You can see that ours slides up and down and is easily temporarily or permanently removed. When the pups are about 3 weeks old, they will walk out of the box onto newspaper to go to the bathroom if they are able to leave the sleeping area. You should have a 2-3" base under it, so that it is off the cold floor. We use 2x2's for the base. We have our 4x4 box within a 4x8' exercise pen, so the pups are safely confined at all times, unless we choose to let them run loose.