How To Fix Damaged Fiberglass Pools

Fiberglass pools are known for durability, but it doesn't mean they can't get damaged. A hole in fiberglass commonly occurs from chlorine, weather, changes in terrain, debris, and constant use. Luckily, you don't have to order a new pool just because it has a hole or cracks. You should be able to fix the damage yourself by following these tips:

Prepare to Fix the Hole

To fix the hole, gather:

  • work gloves and safety goggles
  • dry cloths
  • straight edge
  • pencil
  • scissors
  • putty knife
  • small buckets
  • medium-grit sanding disc or medium-grit sandpaper
  • paint brush paint
  • roller fiberglass paint
  • polyester putty
  • hydraulic cement (optional)
  • fiberglass repair kit

Empty the pool water until it comes to the line, so you can access the crack. Use a submersible pump to speed the draining. Dry the damaged area and six inches around it with a cloth, or let it dry naturally. The surface must be completely dry for the repair to be effective.

Sand the Area

Attach the disc to the orbital grinder, sand the area to remove loose particles; and wipe dust with a damp cloth.  Measure and mark a half inch length around the damaged area.

Connect the diamond cutter to the sander, then grind the section to slightly longer than the marks. You may do the sanding manually, but it takes longer.

Fix the Damage

If the hole or crack is large, you will need hydraulic cement, since the kits commonly only work for small holes. Follow the instructions to mix the cement, spread it with a putty knife, then let it dry. After the cement dries, add a layer of polyester putty, let it cure, lightly sand the area, and wipe sand dust with a dry cloth.

Use the paint roller to apply a layer of gel coat or epoxy from the kit on small holes; making an inch and one-half overlap in all directions. Use a putty knife to even the bonding material. 

Lay a fiberglass cloth or piece of tape from the kit over the wet area, and smooth it with the roller before it dries to prevent air bubbles. Add another layer of gel coat or epoxy, let it cure, then sand lightly.

Clean the sand dust, and paint the area with a matching epoxy gel paint, if desired. After the paint dries, add the sealer from the kit to protect the finish. The sealant should dry completely before you refill the pool.

Frequent hole sin fiberglass pools may indicate structural support. Consider replacing pools with extensive damage. Contact a company that makes custom swimming pools for more information and assistance.