Preexisting coop in frozen MN... I’ve lost my mind!

[DoeAndGander]

You could get a sheet of pressure treated plywood, cut it to fit from the ground to the bottom of the walls. Once in place, pour a few bags of high speed cement into those voids level with the floor inside. You may have to wait for a warmer day but they make Sakrete that sets up within a couple hours.
Another possible fix, just cut and lay sheets of plywood directly over existing concrete floor making sure to cover those gaps all the way to the walls. There aren't too many predators that can lift up a 3/4" sheet of plywood and squeeze between it and a wall.
The windows for light are a great idea. Be sure to put them on the south side because of how the sun traverses the southern sky in winter.
A couple of gable vent with louvers should fix any ventilation problems. That old out building has the potential to be a pretty good coop with a little repair and renovation. You could put egg boxes on the side so you could just reach in from the outside to get them. Would save a lot of floor space. You could also make a small counter with doors below it to store feed, hay, or whatever.
Good luck

A friend of mine suggested a heater and some concrete blankets. I wonder if that would work with your Sakrete idea. Pressure treated plywood is on sale currently too! I’m really hoping to get a solid game plan within next few days. Great ideas, thanks for taking the time to type them all out

 

[EggWalrus]

You may have a piece of "gold" laying there in the shed, that I spotted.
https://www.justcollecting.com/antiques/how-to-identify-a-valuable-disston-handsaw

https://www.vintagesaws.com/

It could be one of the more rare saws and be worth having it restored.
Good luck with the coop!

 

[Percheron chick]

Not the best picture but you get the jist. It's only 4' as that's what I had sitting around. Major PIA.

 

[DoeAndGander]

You may have a piece of "gold" laying there in the shed, that I spotted.
https://www.justcollecting.com/antiques/how-to-identify-a-valuable-disston-handsaw

https://www.vintagesaws.com/

It could be one of the more rare saws and be worth having it restored.
Good luck with the coop!

Wow! You have a great eye for detail. I tried looking at it closer but it’s wedged between the wall and stud and won’t budge. It appears the seal is wood but I’ll definitely be investigating it further as I love antiques and restore whatever I can. I found a really neat pair of old handmade ski’s in the same shed. Im in the process of restoring with hemp oil so I can use them as winter decor

 

[DoeAndGander]

Not the best picture but you get the jist. It's only 4' as that's what I had sitting around. Major PIA.View attachment 1608210

Thanks for the visual! My sister may have some panels laying around. Score!

 

[EggWalrus]

Wow! You have a great eye for detail. I tried looking at it closer but it’s wedged between the wall and stud and won’t budge. It appears the seal is wood but I’ll definitely be investigating it further as I love antiques and restore whatever I can. I found a really neat pair of old handmade ski’s in the same shed. Im in the process of restoring with hemp oil so I can use them as winter decor

I reason it caught my eye and that I knew it was a Disston, was years ago I found one in a barn and looked it up. It was in good shape except for a little surface rust where the original oiled leather cover got wet repeatedly. After fixing it up, I sold it to a collector for $800. Boy did I get lucky that when the one I found was rare.

 

[DoeAndGander]

I reason it caught my eye and that I knew it was a Disston, was years ago I found one in a barn and looked it up. It was in good shape except for a little surface rust where the original oiled leather cover got wet repeatedly. After fixing it up, I sold it to a collector for $800. Boy did I get lucky that when the one I found was rare.

That’s awesome! Cha Ching! Hopefully I can get it unwedged without too much fuss. I will have to keep my eyes peeled at the auctions this summer too

 

[DoeAndGander]

I reason it caught my eye and that I knew it was a Disston, was years ago I found one in a barn and looked it up. It was in good shape except for a little surface rust where the original oiled leather cover got wet repeatedly. After fixing it up, I sold it to a collector for $800. Boy did I get lucky that when the one I found was rare.

Don’t mind the cobwebs! Looks like it may be the D-23 or a replica. It’s lacking a few details. So interesting!

 

[aart]

Sweet saw...have couple similar style and vintage but are Kleen Kutter

 

[EggWalrus]

I don't think it's a D23. It had 4 screws and the medallion, but yours only has 3 screws and medallion. I'll try to look up what model it is later. There should be sone writing on the blade. Wiping it with oil may make it easier to see. That could help identify it also.