The self made Cardboard-Box and Tarp Brooder for the Garage

At the end of the second week, the kiddie-pool brooder became too small for 14 rapidly growing ducklings, also the stench became unbearable so a new brooder was erected in the garage. A couple of cardboard boxes was cut open and glued into a long, semi-circular strip of cardboard, using duct-tape. This strip was placed over two insulating Styrofoam-boards on the garage floor:

Important for the stability of this brooder is that the bottom flaps of the cardboard-boxes are facing the inside of the semi-circular structure, as seen in the second picture.
An 8' x 10' blue tarp was the used to cover the floor and the walls of the brooder with a duckling (poop) resistant surface:

The floor was covered with pine shavings, a large feeder was set up and a non teflon-coated, ceramic heat-lamp was placed overhead:

The Momma Heat Cave and the waterer construction from the old brooder were transferred into the new brooder and finally the ducklings moved in:
full

They like the colder air in the garage as well as having more space to run around. The disadvantage of having the brooder on the floor is that a human looks much larger and much more scarier to the ducklings than from a raised brooder. Also one has to bend down a lot more to refill the food and the water and grab a duckling to weigh.
Cleaning of this brooder should be fairly easy: Remove all equipment and the ducklings, then grab all four corners of the tarp, so that it forms a large bag. The content of that bag can then be dumped on the compost bin, the tarp can be hosed down and re-installed.