If you have a wood front door or garage doors and you want to give them that shiny natural finish, we recommend using a exterior varnish product.   There are several types of exterior varnish, we most commonly use spar urethane which seems to work the best of all the products. If not properly taken care of and watched closely  for even the slightest break down, mildew growth or peeling, it may be required to strip varnish off and revarnish wood.