On Wed, 19 May 2021 08:17:36 -0400, knuttle
wrote:


I have a 10 year old shed for my lawn tools, that is 2X constructions,
with standard particle board siding. While the outside was painted
immediately, the inside of the siding was left unpainted. The doors are
basically a sheet of siding with 2x4 around the edge of each door and in
an X pattern in the bottom half of the doors . The doors overlap the
floor joist and come to the bottom of the floor joist. The minimum
clearance under the shed is about 8" and is open on all four sides.

That area between the door and the joist has started to come a part
Since at this time the decomposition is minor, can i stave off the
replacement of the door by gluing the loose particles and painting that
are of the door?

It works for termites and Swedes, maybe it'll work for you.

Is there a better solution?

Perhaps an epoxe penetrating sealer then epoxe "Bondo".