How to Refinish Fiberglass Doors

fiberglass front door
What You'll Need
Painter's tape
Plastic sheets
Clear lacquer
Mineral spirits or paint thinner

Refinishing fiberglass doors is a difficult undertaking because they are simply so many facets to a door. The door itself is not the only part; when you are planning on refinishing, you must also consider all that surrounds the door to make sure it looks just right and functions properly. Unlike many parts of a home, a door is exposed to all the elements: burning heat, pouring rain, blowing winds, or freezing snow. So, the door has to be finished to withstand all that it will be exposed to. While there are a lot of things to consider, refinishing your fiberglass doors can help you get a new lease on the look of your home.

When you are refinishing something, it isn’t just a matter of stripping and repainting. There are specific parameters that need to be taken care of before the door is going to look right. So, make sure that you understand all the steps before you get started. The following information will help you refinish your fiberglass door the right way.

Step 1 — Find a Well-Ventilated Work Space

It’s recommended that you work in a well-ventilated place. Outside is great, or in an open shed or garage would be fine. You will be working with a lot of chemicals and dust, so you’ll need to be somewhere that won’t collect the fumes and become unsafe for breathing and working.

Wear a breathing mask and goggles to be certain that the fumes don't hurt your eyes or lungs.

Step 2 — Remove the Door From Its Hinges

The door you're working on must be pulled down to complete this job properly.

Tip: You need to find a way to place the door flat enough to work on it, but not directly on the floor as paint and stain cannot dry this way. Many people put the door on two saw horses to balance it off the ground as they work, moving it as needed.

Step 3 — Remove All Door Components and Accessories

Once the door has been removed and relocated into a safe work area, all its components must be stripped: door knobs, letter boxes, knockers, doorbells, etc. They should be easy to remove with a simple screwdriver. Put these things to one side, or you can leave them to be cleaned while the topcoat is drying overnight.

You can use the tape to put plastic or newspaper over any glass in order to protect it.

Step 4 — Strip the Surface

You need to take all the stain and paint off the door. Check with the manufacturer of the door to make sure you get the right products to complete the task efficiently.

Most likely you will be using a strong chemical, such as a paint thinner, so make sure you work safely with safety eye wear and a breathing mask. Cover your hands so that they aren’t injured by the stringent chemicals or the coarse cleaning materials.

You’ll need to use a steel brush or a copper wool sponge with the chemical agent in order to strip the paint or stain from the surface.

Step 5 — Sand the Door

You’ll want to wait a while before you start sanding. However, sanding is important and can be incredibly time-consuming because if any speck of paint or stain is left, it will make the new refinishing job uneven.

You need to use three different types of sandpaper to complete this job. Start with a coarse macro grit to remove any large areas of paint or stain. Then use a medium-fine grit to level out the surface. Last, use a very fine micro grit to smooth the door perfectly.

You will need to make the door as smooth as possible and as even as you can get it. If there are parts that are uneven or covered in stain or paint, your new finish won’t adhere properly, and you’ll have to start all over again. And no one wants that.

Be sure to wipe the surface with a clean, damp cloth to remove all debris.

Step 6 — Stain or Paint the Door

Fiberglass doors typically have a wood-grain finish, which looks beautiful with a nice stain. However, if you prefer paint, you can apply an oil-based primer, wait 24 hours, and apply a coat of oil-based paint. Two coats of paint should cover it sufficiently. (Oil-based primer is recommended, as is latex enamel exterior grade paint, because both can withstand the wind and the rain without chipping, peeling, or dripping).

Otherwise, if you're looking for a more traditional fiberglass door finish, the surface needs to be stained. Once again, check with the manufacturer of your door to see what is the best kind of stain or lacquer to use on that type of wood.

After making sure that you have covered every crevice with stain or lacquer, wipe off all the excess. Stain on the surface of a door dries quickly, especially if it clumps, so make sure to wipe off imperfections as soon as possible.

It can take over 24 hours for the stain to dry completely. Repeat this process two to three times for the best results and saturation.

Step 7 — Refinish Door Frame

While you shouldn’t remove the frames from your home, the door’s frame should be treated the same as the doors. They need to be stripped, sanded, and stained. Again, remember to tape up all the fiberglass to avoid damage.

This will be a much simpler job than the door was because there is less surface area that needs to be taken care of. You can also give this 24 hours to dry.

Step 8 — Apply Lacquer (If You Chose Stain)

If you chose paint, this step is unnecessary. However, if you chose to stain the door and frame, you should apply two or three coats of lacquer using a lacquer brush. Clear spar lacquer is recommended for exterior fiberglass doors, as it holds up well against the elements.

Step 9 — Reattach Door, Components, and Accessories

Once the door and frame are completely dry, you can reattach any accessories to the door and secure the door onto the hinges.

Overall, refinishing a door can be a pain. However, if you do it with patience and make sure you follow every step you can have a great looking door that will help liven up the exterior of your home.