How to Paint FRP Panels? (Easy Steps and Tips)

Fiberglass reinforced panels (or FRP) are thin plastic panels or flexible sheets that are made by integrating strong polyester resin reinforced with fiberglass.

In simple terms, it’s a composite material that is made of a polymer matrix reinforced with fibers (usually glass in fiberglass, carbon in carbon fiber reinforced polymer, aramid, or basalt).

The good thing about the FRP panels is they can be directly installed over the drywall, wood, concrete, and a variety of other solid surfaces. So, these are today widely used on interior walls and ceilings for added style, durability, and hygiene reasons.

How to Paint FRP Panels?

Because they have built-in color and are reinforced to reduce surface damage, Fiberglass Reinforced Plastic (FRP) is NOT designed to be painted.

This is particularly true because the surface is not designed to stick to paint. This non-stick surface makes cleaning the FRP easy, but the paint has a difficult time sticking.

However, most FRP surfaces may be painted if you do the proper preparation.

There may be exceptions depending on the manufacture and design of the FRP. So, you will need to check first before you decide to paint to ensure that it will work.

Choosing the right paint for FRP

For painting FRP panels, the two categories of paint that are most suitable are polymer-based epoxy and polyester. Ideally, you should pick a high-quality paint that matches the resin type of the FRP for outdoor use.

This is because it has the best chance of sticking to FRPs that have had their surface properly prepared.

Remember that low-quality paint or latex paint will tend to peel, flake, or chip easily because it will have a difficult time sticking. But you can use high-quality acrylic paint for FRPs that will remain indoors.

For FRPs that will be exposed to sunlight or used in delicate outdoor environments, using high-quality epoxy paint or polyester-based paint is best.

Once you have chosen the best paint for fiberglass, be sure to obtain the right type of brushes, sprayers, or rollers to apply the paint on smooth FRP panels. You can choose the type of application that best suits your needs.

 

Preparing and painting the FRP surface

After you have obtained the paint and supplies, you’ll need to prepare the surface so that it will allow the paint to stick. Otherwise, you’ll find the paint sliding off the surface rather quickly.

Even paint that does manage to stick will not look natural and brush strokes along with uneven coats will definitely show.

Step 1 – Wash

Run water over the FRP until you have thoroughly washed the surface. If needed, use a mild detergent solution to remove any dirt and grime accumulated. Once clean, wait for the FRP to dry.

Step 2 – Scour

Use fine-grit sandpaper to scour the surface. Your goal is to make the entire surface of the FRP rough so that the paint will stick.

Step 3 – Primer

You’ll want to use acrylic primer on the FRP. Be sure to smooth it out using a brush with wide bristles.

Apply the bonding primer to all FRPs first and then wait for them to dry. In most cases, this should take a couple of hours.

Once the primer is applied, you should clean any residue from your brush.

Step 4 – Paint

Once the primer is fully dry, apply a single coat of paint to each FRP and wait for the paint to dry. If you still see primer showing through the paint, apply another coat.

Keep in mind that applying multiple thin coats yields the best results, providing even coverage without drips. So, use clean brushes or rollers and apply the paint in long, smooth strokes, starting from one side and moving systematically across for a uniform finish.

And now you have successfully painted an FRP. You can repeat the same process on as many FRPs as you like.

Tips and Warning When Painting FRP

One of the biggest challenges with painting fiberglass textured wall panels is its preparation before painting without which you will have a hard time refinishing your panels.

Preparing the FRP panels for painting often needs some sanding (to allow the paint to stick better) which may expose you to the fine fibers that escape into the air.

So, to let the fine fibers disperse safely in the breeze when you sand, it’s best to prepare the FRPs outdoors. Also, as a precaution, you’ll need a respirator to cover your mouth and nose to prevent inhaling the fibers.

After all the preparation done to address the adhesion challenges, it’s good to test the paint compatibility on a small, inconspicuous area before you exactly start your project.

Do I Need a Topcoat for Painted FRP Panels?

FRP boards are often installed in kitchens, bathrooms, and industrial settings where humidity and water exposure are high.

Due to their durability, weather resistance, and low maintenance, these are also commonly used in various outdoor home applications such as exterior walls, facades, porch ceilings, garden sheds, outdoor storage areas, garage walls, decorative fencing, signboards, greenhouse roofing and much more.

So, to ensure that the paint lasts on the FRP panels it’s recommended to use a clear topcoat after the paint job is completed and the paint is dried.

By forming a waterproof barrier, a clear sealant (polyurethane, acrylic, or epoxy-based) designed for FRP surfaces prevents water penetration and reduces the risk of paint deterioration, fading, and discoloration. This type of clear sealant is especially beneficial in harsh conditions where the area is exposed to moisture, chemicals, and UV rays.

A sealed surface is also easier to clean and maintain, as dirt and grime don’t adhere as easily to the smooth finish. Just make sure that you apply thin, even coats of sealant with a brush, roller, or spray gun to avoid bubbling.

The Bottom Line

A fresh coat of paint can breathe new life into worn-out FRP panels, refreshing your space without the high cost of replacement. Different finishes—matte, satin, or glossy—can also enhance the room’s ambiance to suit your style.

Make sure that you follow all the steps correctly and sand the surface before painting to avoid getting poor results. Also, for moisture-prone areas, consider paints with built-in mold and mildew inhibitors to improve durability and maintain a cleaner surface over time.