One common problem you may face when you have wooden French doors is that they can eventually rot, especially the exterior part of the doors since they are exposed to the elements, such as water and sunlight. While they may be unsightly, partially rotten French doors that still work perfectly do not need to be replaced. They simply need restoration.
If the rotten area is very small, you can fix it by just applying resin glue directly to the rotten spots. If the area is quite large, you should remove the door from the jambs, and then remove loose particles and wood fibers from the rotten area using a wire brush and then a paint brush. The next step is to make the resin glue by mixing the glue powder with water and then apply it to the rotten area. Once it’s dry and the excess glue has been scraped off, sand the area and apply Danish oil. Let it sit overnight and reapply the next day before rehanging the door on the jambs. Get more details here.