We live in Maine, where it gets pretty chilly. Our ducks (silver Appleyards) have an elevated duckhouse attached via a ramp to a predator proof, covered run. We allow a little over five sq ft per bird, but as others have said, four sq ft per bird is a pretty common target for most folks. Ducks do great in cold temperatures once they have their adult feathers. The most important thing is to make sure they can get out of the wind. In the winter, we wrap three sides of the duckrun with 6mil plastic to give them wind protection. We don't bank with straw anymore like in the picture below, as it was really unnecessary, but you can see the plastic. We staple the plastic in place and then screw wood strapping over it to hold it in place. Even in serious blizzards and gales, it holds up great.
Our duckhouse is uninsulated, and we use the deep litter method. We start with several bags of shavings and then add straw as needed. We spot clean 2x/day and clean out once or twice a year.
All of our windows in the duckhouse have plexi sliders so we can adjust based on the weather. Ventilation is critical (especially when it's very cold!). We have four windows in the duckhouse. The two that face into the covered run are almost always fully open, and the others are adjusted for weather.
We installed a Sweeter Heater in the duckhouse this past winter. External heat is NOT necessary. We decided to add the heater to give our girls a little boost in the winter as they age. Some of them really like it, while others ignore it. We would not use a heat lamp or other heat that is high fire danger and too intense of a heat. Sweeter Heaters are radiant heat that just warm the birds that are directly underneath it.
In terms of water, we use a heated 5-gallon bucket in the run. We change it twice a day. On very cold nights we supplement their feed (we use Mazuri Waterfowl Maintenance) with corn or scratch.
Keep us posted, and feel free to reach out with other questions!
