Leigh Ramsdell and Hal Brindley with The Environmentals discuss how to build a worm composting bin. To build a worm composting bin, you will need a plastic tub or a box with a lid. Calculate one square foot of surface area per pound of worms. A pound of worms can process a half a pound of food per day. Worms need air so put holes in your bin on the top and sides. Also put holes on the bottom for drainage so your worms don't drown and die. Add screens to cover the holes. Put bricks on the bottom of one bin and add another bin on top of it. Shred half inch strips of newspaper and moisten them to get them damp. Add worms, like red wigglers and pot worms, to the bin. Add the shredded newspaper on top of the worms. Finally, add your compost between the newspaper and worm layer to utilize your worm composting bin. Worm bins don't smell.