Overview

• Zedcor Wholly Owned/PhotoObjects.net/Getty Images
  
  While fiberglass seems ubiquitous today, it may be surprising to learn that it was actually invented by the ancient Egyptians and the Pheonicians. These ancient civilizations made glass into fibers. It was in the 1950s Dale Kleist, a Corning Glass engineer, came up with the method--by accident--that is used today to produce fiberglass products. While these doors are durable, you may find that they may need to be repainted. Fortunately, this is something you can do in an afternoon.
  
  

Preparation

• Prepare for staining by removing all of the hardware from the fiberglass door. Take off the weatherstripping and the sweep at the bottom of the door. You can reinstall all of these things when the door is finished. If your door has a window or windows, remove the excess caulking around them with a razor. After you've removed what you can with the razor, clean the glass with window cleaner.
  
  

Cleaning

• In order to be sure that you get the finish you want, clean the door thoroughly. Wash the door with a mixture of liquid soap and water to remove any trace of grease, oil and dirt. After you've washed the door, rinse with clean water. Let it dry.
  
  

Apply the Stain

• Apply the stain with either a brush or a rag. If you are applying the stain with a rag, dip the rag in the stain then apply it to the door by rubbing it on with small, circular strokes. Do a little section at a time until you have covered the entire door. With the brush, take your time applying the stain and try to do so with even strokes, blending in each section with the one before it. If you make any mistakes, you can fix it by dabbing it with mineral spirits and painting over that area again.
  
  

Apply the Stain

• Picking out the color can be tricky. Test the color of the stain on the hinge area first, where it won't easily be seen. Once you're satisfied with the color, apply some stain. Stain the hinges as well.
  
  

Adjust the Color

• If you wish to have a lightly colored door, use a brush to wipe off much of the stain after it dries for a little while. The resulting color will be thin. However, if you wish to have a darker color, then let it dry for a longer period and reapply lightly.
  
  

Drying Time

• Allow the fiberglass door to dry for at least 48 hours. To make sure the stain is dry, press a little masking tape to the door, rub it with the handle of a paint brush and remove the tape. If any stain adheres to it, then the door needs to dry a little longer.
  
  

Finish Coat

• You will need to apply two finish coats on the door. These must be applied quickly and thinly in the direction of the grain. If you apply the finish coat too thickly, it will not dry properly. Apply the second coat after the first coat dries for at least 4 hours.