This is the whelping box we designed and have used for all our litters here at Perennial. We provide the plans here at no charge ~ the dimensions can be modified to suit bitches of difference breeds and sizes.
There is no bottom in the box. For each litter, we purchase a remnant of vinyl flooring, and use that as a bottom. The side of the box rest on the fabric bedding (we use flannel sheets or lengths of polar fleece) with incontinence pads (or newspaper) underneath.
List of Materials
2 boards 1" x 12" x 8'
2 boards 1" x 6" x 8'
2 boards 2" x 4" x 8'
4 mending plates
8 - 1" bolts with nuts
1 quart latex high-gloss paint
5' x 5' sheet of clean, new vinyl flooring