Nope. House is over 100yo, we are the 4th owner. I think the 2nd owner, sold it in early 1990's, was the owner that did this. The storm windows are easily 50yo. Looks like 1 x 2's or 2 x 4's and then a front storm door with a VERY old small bolt that locks it.
You could contract somebody to enclose yours. DH would love to expand it south and have a wood burn stove put in to warm it up in the winter.
I can understand. Additions to the exterior alter the architectural facade that someone may have spent a good deal of creative effort designing.
That major design feature may be lost to functionality. And, it looks like it.
The dog trot, or possum trot as @journey11 tells us, is about nothing more than function from the ground up. On that linked page the architectural outfit has put online, you can go from one image to the next, photograph of real life or drawing of what's imagined, and it's function, function ... maybe it's a little bit fun ...
Imagine the environment. Imagine interacting with the environment from that "domicile." The largest picture looks like there is a clean slate around the building. I'd be out measuring the corners of my yards, fields and pastures. Fitting outbuildings in where they are needed.
Ya know, if I look straight ahead ... from my nose to the tip of my finger digitS' it's exactly (enuf) 1 yard; my foot in my clodhopper is 12 inches; my thumb is an inch wide.