I've seen several posts over the last few years asking about shelter for winter. I inherited a large 48' 3-sided shed and small barn when I purchased my acreage and used my barn for shelter the first year I had goats.
There were a couple issues I had, first was storing feed. The little goaties were magicians about getting into feed! The other issue was the spring clean out! It was awful. I was also worried about what all the manure and urine would do to the dirt floor.
The 2nd year I tried tarps across the 3-sided shed to keep the worst of the wind/snow out and it worked, but between the goats eating the plastic and strong winds it really wasn't the best option.
After some brain-storming and online searches I came up with the idea to put plywood across the front of the shed. This worked great! We put the front on the shed usually around Thanksgiving and pull it down again as soon as the temps stay in the 40's overnight. It takes about half a day to put up and take down, well worth being able to open the shed back up in the spring! It also makes it much easier to clean out in the spring.
First we add gates across the front of the shed:
Then we drilled holes that lined up with the rails on the gate, then using zip ties we attached plywood to the gate bars:
It actually fits better when you attach the plywood to the back of the gates (the opposite of what is pictured below) or if you overlap the plywood at the corner. In the picture you can see how the corner has a gap. Easy to fix!
The nice thing is that you can take the plywood down, store it and use it over and over again. Purchasing decent quality plywood isn't cheap but considering this is the 3rd year I've done this and the boards are still in great shape the benefit outweighs the cost!