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Staining a Fiberglass Door

Finishing Fiberglass Doors TIPS

Must Be Clean

The fiberglass door must be perfectly clean to achieve the best results.

You can't assume the door is clean.

Most oils are clear and you'd have no idea they're on the surface.

The stain or paint will not bond well if the surface is dirty.

You can do it with a standard soap and water solution such as Top Job, Dawn Dish Soap or any other liquid type soap. Rinse the door with clear water and dry it. The door must be dry before you stain it.

CLICK HERE to get FREE & FAST BIDS from local painters that specialize staining fiberglass doors.

Deep Cleaning

Oxygen Bleach

Stain Solver is MADE in the USA with USA ingredients that are food-grade quality. CLICK THE IMAGE to order some NOW.

If you want to deep clean the door removing all mildew, algae, oils, etc. then use Stain Solver.

Stain Solver is made in the USA with USA ingredients. It's a pure powder you mix with warm water.

Once dissolved, you can brush it onto the door. Work in the shade keeping the door wet with the solution for about 15 minutes.

Follow up cleaning with liquid dish soap solution, rinse well and allow to dry.

Most fiberglass doors allow you to use mineral spirits to clean the door, but never use turpentine! Follow the finishing instructions that come with your door if you have them.

Stain Colors

If you have a new door, look at the stain kit. Most have some sample pieces of fiberglass.


The stain in this kit was specially formulated for fiberglass doors. It's not NORMAL oil stain for wood. CLICK HERE NOW TO GET THIS AMAZING STAIN KIT.

You use one of these to test the stain color. If you don't have a scrap, well, you may be out of luck. If the hinge edge is fiberglass (most are), then you can try to sample the color near the bottom of the door on this edge.

Depth Of Color = Time

Stain color can be adjusted by the amount of time you allow the stain to sit on the door / sample before brushing and how much pressure you apply when brushing. If you want a lighter color, let the stain sit for a short while and remove lots of it with the brush.

Do the opposite for a darker look.

Rub in Circles

The stain is applied to the door with a cloth rubbing it in a circular motion. Work from the center of the door to the outer members. Don't try to do the entire door at once. Work in small areas and feather out stain in overlap portions.

Don't forget to stain the fiberglass sample. You'll need this finished as well as the door. You'll use the sample to test the door for gloss loss due to sun exposure.

CLICK HERE to get FREE & FAST BIDS from local painters that specialize staining fiberglass doors.

Stain Must Be Dry

Most fiberglass stains need 48 hours to dry. You can test for dryness by applying a piece of acrylic painters masking tape to the door or better yet, to the fiberglass sample.


Use this kind of tape to do the *dry-stain* test. CLICK THE IMAGE NOW TO ORDER THIS MAGIC TAPE.

Rub the tape with a piece of wood or knife handle. If the stain is dry the tape will be clean when you pull it off the stained object. If the stain is dry, you are now ready to go to the final steps.

Applying the Top Coat

Here is where many people goof up. The temptation is to apply thick coats of finish to protect the door.

Most fiberglass door manufacturers want you to apply two thin coats.

IMPORTANT TIP: Thick coats will not dry properly. Try to coat the door in a dust-free environment if at all possible.

Milky But Clear

The top coats often look like thin milk.

Don't panic! If you apply them sparingly they'll dry crystal clear. Avoid dipping the entire brush in the clear coat. Try to just get the tip of the brush wet.

VERY IMPORTANT TIP: Work quickly and don't over brush. Apply some in an area and move on.

If you brush back and forth over the same area too much, you can dissolve the stain! Always brush in the direction of the grain! Work from the center of the door out towards the edges.

Don't forget to apply a clear coat at this time to the fiberglass sample if you have one.

The Second Coat

Follow the instructions on the top coat container. Many will indicate a short drying time of less than 4 hours.

Don't sand the door after the first coat.

Apply the final coat as you did the first coat. The surfaces normally look wet when you apply a thin coat - not milky.

A milky appearance may be a clue that you are applying too much finish.

Painting a Fiberglass Door

Several readers wrote to me asking if they can paint a fiberglass door. Absolutely!

You paint one as you would any exterior surface. Clean the door with soap and water and allow it to dry.

Use a latex primer matched to a 100 percent acrylic top coat paint.


This is a special paint formulated to BOND to fiberglass. It can be tinted. CLICK THE IMAGE TO ORDER IT NOW.

Remove Weatherstripping

I always like to remove the weather-stripping if at all possible. This allows you to work more quickly and keeps the door from sticking to the weather-stripping.

Keep the weather-stripping out of the door if at all possible for a week to 10 days. This drying time will allow the paint to fully cure and harden. If the paint is tacky it can stick to weather-stripping.

CLICK HERE to get FREE & FAST BIDS from local painters that specialize staining fiberglass doors.

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15 Responses to Staining a Fiberglass Door

  1. I have a fiberglass entrance door that gets the full morning sun and is peeling of a clear coat, because it looks like it got sunburn and is now peeling! How do I remove the rest of the clear coat and what would be a good product to apply a new clear coat?
    Thank you, Bill

  2. I would like to paint my fiberglass door with an enamel paint. It is currently stained and sealed with polyurthane. What do I have to do to get it ready?

    • Andrea, your question requires lots of typing, plus I have some questions for you so I can give you the correct answer(s). I only do pithy answers here in the comment section. If you want to protect the investment you have in your house and not waste time or money *hoping* you make the right decision, you should talk to me on the phone for just 15 minutes. It'll be the best investment you've ever made in your home!

  3. When painting a fiberglass entry door, I got an area too thick. I rubbed out this area, but now have a spot that is peeled off or blotchy. Can I just sand that area out and repaint?

  4. We just stained our fiberglass front door with a gel stain. It took almost 72 hours to dry because of low temperature and very high humidity and the cold humid weather is expected to continue. The door never receives direct sunlight and only limited amount of splashing water. Would a topcoat (spar urethane or others) be required? Can we wait a month for better weather to add the top coat? Also is there anything wrong or a huge disadvantage with the spray spar urethane?

  5. I am painting the front entry door. I want the inside of the door to be the white of the inside trim but the outside to be a color. Where, on the edge of the door, do I make the transition from white to color? Should the color be flush with the front, wrap around the four edges, or something in between?

  6. Bill, whenever you're painting a door you paint the edge the same color as the room that the door opens in to. In the case of your front door it opens into the room in your house so it should be painted the color of that room. You indicated white. So paint the edges white. However, if there is already a solid coat of paint without chips on the top and bottom of the door don't bother painting those surfaces. They can't be seen anyway. It can cause the door to rub if they get painted too much. You really only need to include the lock and hinge edges.

  7. hi, can I stain or pain over an existing stained fiberglass dark brown garage door? I want to restain or pain it lighter. its a home in florida, thanks

  8. We have a fiberglass door that has a door skin. The front of the door is painted a dark blue and the inside view of the door is white. What are our options? We would love a brown or stained look on both sides. Can we replace the door skin? Should we just paint over the blue? or can we sand the blue off and start over? We also get lots of sun and this door get so hot. Any help is appreciated.

  9. Hi, we recently stained our new fiberglass door and it looked great, but the second coat clear coat did not dry clear (it is still milky in places). From your post it sounds like maybe we applied it too thick. Is there any way we can save our door?

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