How to Repair a Damaged Fiberglass Deck

Lead Image for How to Repair a Damaged Fiberglass Deck
  • 4-6 hours
  • Beginner
  • 150-1,000
What You'll Need
Fiberglass cloth material
Fiberglass filler like Bondo
Support plywood
Masking tape
Hard wire brush
Acetone cleaner
Safety goggles
Fiberglass gel coat

Repairing a fiberglass deck is moderately challenging, but you can repair it yourself with a bit of patience and grit. Repairing yourself lets you save on costs for professional repair and also saves a lot of precious time. Repairing a deck not only becomes necessary from time to time but also increases the durability and life of the fiberglass deck. Moreover, a fiberglass deck has to be checked for damages so that the look of the entire deck is not spoilt due to any small defect that is unnoticed.

Step 1 - Initial Steps

Locate the area of the deck that needs repair. This place must be cleaned thoroughly before proceeding with any repair. Use 80-grit sandpaper and roughen up the surface of the deck. Sprinkle some acetone cleaner and wipe clean with a piece of rag. Make sure that you work in an open area with safety goggles on.

Step 2 - Positioning Supports

Wherever on the fiberglass deck, you need to work, make sure you perform the repairs from the underside of the place. For making support take a 1/6 or 1/8 inch plywood and tack it on the outside part of the area to be repaired. You can tape the ply on to the surface using masking tape along all four edges of the wood.

Step 3 - Roughing Up

Check if the acetone applied has dried up and if the support board is firmly in place. Now take a hard-wire brush and rub the area surrounding the place where the repair has to be done. Roughening up is an integral step as the fiberglass coating needs a rough area to hold on.

Step 4 - Repairing

Cut out the required amount of fiberglass cloth that you purchased from a hardware store. The quantity cut out must have an overlap of about 2 inches over the area that is damaged. Keeping the plywood support in place, take the Bondo brand filler and apply it in a thin coat so that the damaged part gets filled.

Do not keep applying coats in a hurried way, take time for the coat to tighten up a little and then apply more if needed. When you see that the damaged part is totally filled, sand up the last layer of the filler and apply the fiberglass cloth on it. Next, apply two coats fiberglass gel as required and again sand up the final layer in a smooth finish.

In order to repair the exposed surface of the deck, stretch the cloth over to the place of repair. Apply a coat of fiberglass gel and leave to dry. Repeat the process elaborated above to fill up any damages and finish up in a similar manner. After the repairs have been completed, sand the surface all over again with sandpapers of 100, 220, and 400 grits, one after the other.