See if the panel is held in place by molding on one side. If it is,replacment is straightfoward. If not you might try a deck wash that bleaches discoloration from the wood alowing restain. The rails and styles look good enough to sand,stain and clear coat.

Al I wad looking for advice thoughts on all three. I can a restrationist in the area suggest reinforcing the middle piece as it is really to thing for an exterior door nowadays. Maybe 1/4 inch and thats generous. It is not loose at all but

i can tell how it was put together. Taking it somewhere is not really an option as I don't live in the kind of neighborhood where one could go without a door and I have a hard time getting contractors to come to me where i live this is the price of living in a older. So will probably be a diy.I do not think it is trim holding it on it looks to be in a channel.

OK so if the real issue is to remove the panel and replace it with something thicker, and the molding is not nailed on, your either have to cut the molding off one side (router) or disassemble the door. You are still only going to have a 1/4" groove to work with.

The strongest replacement would be a 3/4" or 1" piece of plywood. Putting a 1/4" tongue on every side will be the weak point if someone was to kick the panel in. So the grove would have to be opened up allowing a thicker tongue (assuming the door is 1 3/4 or more thick. Changing it from one panel to two with a center style of solid wood would make it even stronger.

You are getting into major rework here in order to maintain the character of the door. I don't see how you can get this done in a day and do it correctly. Think about sealing up the opening while the door is being worked on in your shop or at someone else's.

I'm not optomistic you will be able to complete the project in a single day and rehang before dark when "buggers" start prowling. However I will play along for now. I see only two ways to replace the panel with a thicker one. Plan (A) totally disassemble door ( challenging but the best way),increase width of groove holding panel. That will remove part of profile surounding panel. If preservation is important,cut new wider goove with a stile bit so it makes new profile. (B) remove perimiter profile plus depth of groove on one side with straight router bit. Install thicker panel then trim to hold it in. i really feel it's a tall order to do this door with only net advice. I also figure a pro would possibly hang a temporary door while this one was in the shop. I couldn't do it on your front porch but then I'm slow.

Temporary door good idea.

for reference here is the front of the house. Not having use of the front door is not an option as the back is not easily accessible.

I see that your door has lost it's finish in some areas. For it's looks you could sand and refinish it. As for reinforcing it I think you are better off getting a security door if front of it. You already have a storm door, whats the difference?

I have an antique storm door I am having redone. I'd never put a security door on my home.

No helpful ideas here, but just wanted to say I love your antique glass doorknob!

Thanks

My uncle, whose front door is almost identical to yours, is currently in the same boat as you. His house is 100 years old, full of now extinct chestnut, which he painstakingly stripped of multiple layers of white paint. All of the woodwork is now just gorgeous! He's really a great steward of the family homestead. Oh, back to the front door! He's replacing it. :-)

Chestnut is not extinct. It just doesn't grow to a size that can be cut for lumber anymore. It dies when it is very young. Forestry experts are trying to develop a blight resistant American Chestnut.

http://plantclinic.cornell.edu/factsheets/chestnutblight.pdf