Help for roof ideas for very large cat enclosure
Under conditions of low wind even a wire &quot;roof&quot; can pick up a lot of snow load.
So, a large roof area like that will require a lot of support, even if it's wire fencing. That can be provided by rows of posts with heavy wire to support the fencing between posts, and you could exploit the posts as support for cat entertainment, perches, etc.
Whether your cats will want to be out there once the snow makes it through to the ground may vary with your cats (or even with the age of the cat, most of mine got disgusted with snow after the first year or two.) Our very furry robust barn cats basically burrowed into the nests they made (we helped by stacking bales to make a starting cavity for them) in the hayloft and patrolled inside the barn over winters, rather than roaming out through the snow. Our indoor cats rarely spend much time at all outdoors in winter, and prefer areas without snow when they do go out.
A solid roof may have a lot more impact on your property taxes than a wire &quot;roof.&quot; One possible intermediate approach would be greenhouse film (sheet plastic, but sturdy and UV resistant for years) which is not normally classed the same as a &quot;permanent structure&quot; for tax purposes. You'd need to support it in a manner that would shed snow, and that might be difficult, expensive, or require changing your plans if the fences you are using for walls are also boundary fences (can't just dump snow on the neighbors property.)