Things You'll Need
Masking or paint tape
Plastic garbage bags
Clock or timer
Soft, lint-free rags
Warm, soapy water
Polyurethane or other clear topcoat sealer
Fiberglass doors are attractive. Even better, they require less maintenance and have fewer problems than steel or wood doors. However, they do need staining or painting every three to five years. If your fiberglass door's stain coat is flaking, chipping, or peeling off unevenly, you'll have to remove the layer before applying a fresh stain coat.
Remove the Previous Stain
Remove the door handle or wrap it with plastic bags and masking tape. Cover the door hinges and any other objects (such as a doorbell) with masking or paint tape.
Lay a thick layer of newspapers on the floor under the side of the door where you will be working.
Apply the stain stripper. Most strippers direct you to lightly spray or paint on the stripper, allow it to sit for a minute or two, and wipe off with a rag.
Wipe off the stripper with a rag. Clean the door according to manufacturer's instructions (usually warm, soapy water with multiple fresh water rinses). Allow the door to dry completely.
Stain the Door
Open the can of stain and very gently stir the contents with the paint stick. Be careful not to create bubbles in the stain.
Dip your brush into the can to get an inch of the brush coated, and allow the drips to flow off your brush. Tap the brush on the inside rim of the can to rid excess drips.
Apply the stain. Go in the direction of the grain of the door. Work the brush in long movements. Apply the stain in thin layers; it is better to apply multiple thin layers than a very thick layer.
Stir the stain gently in the can occasionally, to keep the colors and solvents blended uniformly. Allow the first coat to dry.
Repeat steps 3 through 5 for a second coat. Repeat again, if necessary. Allow the door to dry for 24 to 48 hours.
Apply the Clear Topcoat Sealer
Open the can of sealer and stir very gently with the paint stick. Avoid creating bubbles in the sealer.
Dip your brush into the can to get an inch of the brush coated, and allow the drips to flow off your brush.
Apply the sealer in a thin, even coat with long brush strokes. Start with the door panels and around any decorative trim. Go in the direction of the grain of the door. Work in thin layers; it is better to apply multiple thin layers than a very thick layer. Allow the first coat to dry for two to six hours.
Repeat steps 2 through 4 until you have applied three or four coats.
If working indoors, open windows and run an exhaust fan to remove vapors.
When applying stain, it is best to paint the decorative door panels and jambs, and then apply stain to the larger sections of the door last, to provide a more uniform appearance.
Some fiberglass doors are pre-coated by the manufacturer with a top-coat primer. Do not remove this primer coat. See your door manufacturer for specific instructions on removing stain before re-staining.
Wear gloves and safety glasses when working with chemicals.
Test the stain stripper on an inconspicuous part of the door before using fully, to ensure that the stripper does not damage or irreparably stain your door.
Always follow manufacturer's directions and safety warnings when using chemicals.
Never sand the fiberglass door with sandpaper or other abrasive materials.