We have two buildings with Mahogany Doors with Southern Exposures and the finish on the doors is peeling off after only a couple of years. I believe the finish is some type of varnish.

What is the best way to finish the doors so that they do not peel when exposed to the sun? Is there a finish used on wooden boat trim that takes the sun well? Someone suggested a solid stain for the doors. Someone else suggested some other type of finish that completely contradicted the guy who recommended the solid stain. Who should I believe. Thanks in advance for any help.

Bob