I wont knock anyone for trying not to freeze but the other alternative you are facing is burning to death so choose wisely.Well at the time it was either that or freeze so. Guess I’ll have to get it looked at.
You should consider getting double wall pipe at least. That has a minimum clearance of 2". Also, any horizontal runs should have 1/4" pitch per 1 foot horizontal. The double wall pipe can be expensive but so it rebuilding a house. I would strongly suggest you contact a knowledgeable chimney installer and see what it will cost you to get a proper chimney.
Also, you should move that steel plate out to cover more of the floor in front of the door. Embers can fall out and go further than you think. Keeping the area under the door clean is important so if something falls out it doesn't catch on fire.