Common Fiberglass Pool Problems & How to Prevent Them

Fiberglass pools offer incredible durability and low maintenance, yet even these modern marvels aren’t immune to certain challenges. Understanding common fiberglass pool problems before they occur is the difference between decades of carefree swimming and costly repairs that could have been prevented.

Many homeowners choose fiberglass for its smooth surface and quick installation, only to be caught off guard when issues like spider cracks or wall bulging appear. With proper knowledge and preventative care, you can enjoy all the benefits of your fiberglass pool while avoiding the pitfalls that frustrate unprepared pool owners.

Why Fiberglass Pools Face Certain Issues

Fiberglass pool problems typically stem from three main areas: manufacturing quality, installation methods, and ongoing maintenance practices. Most issues affect the gelcoat (the smooth surface layer), the structural shell, or result from improper backfilling around the pool. Understanding these potential challenges helps you make informed decisions when purchasing and maintaining your fiberglass pool.

Top Challenges Homeowners Encounter

Spider Cracks and Gelcoat Fractures

Spider cracks appear as fine hairline fractures in the gelcoat surface of fiberglass pools. These typically result from impact during transportation or improper handling during installation.

While usually cosmetic rather than structural, these cracks can be concerning for homeowners who’ve invested in their backyard oasis. Quality manufacturers use flexible gelcoats specifically designed to resist cracking.

To prevent spider cracks:

• Choose reputable manufacturers: Look for companies with proven track records for quality construction
• Ensure professional transport: Work with experienced pool delivery specialists
• Address small issues quickly: Minor cracks can be repaired before they worsen

Surface Discoloration and Fading

The beautiful surface of your fiberglass pool can develop discoloration when exposed to improper water chemistry. Maintaining balanced pH levels between 7.2 and 7.6 is crucial for preserving your pool’s appearance.

Test your water chemistry weekly and adjust as needed to prevent staining. Use only non-abrasive cleaners specifically designed for fiberglass surfaces to avoid damaging the gelcoat.

Bulging Walls or Structural Shifts

Bulging walls occur when the backfill material around your pool shifts or when groundwater creates pressure against the shell. This problem is almost always related to installation practices rather than the pool itself.

Proper installation using clean, crushed stone or gravel backfill helps prevent wall bulging by allowing groundwater to drain freely. Sand backfill, while sometimes used, can wash away or shift over time.

Osmotic Blistering on Gelcoat

Osmotic blisters appear as small bumps on the pool surface when water molecules penetrate the gelcoat and become trapped in the laminate. These blisters typically develop due to manufacturing defects or prolonged exposure to imbalanced water chemistry.

Quality manufacturers use vinyl ester resin barriers to prevent water migration into the laminate. Regular inspection of your pool surface can help identify blistering early, when repairs are simpler.

Impact of Hydrostatic Pressure

Hydrostatic pressure is the force exerted by groundwater pushing up against your pool shell. This pressure becomes particularly problematic when draining your fiberglass pool, as it can cause the empty shell to float or shift. In winter months, pay attention to frost heave potential for pools installed in particular types of soil. 

Never completely drain a fiberglass pool without the guidance of a professional. Most quality pools include hydrostatic relief valves that allow groundwater to enter the pool if pressure builds up.

If you need to lower your water level:

• Never drain completely: Keep at least 2/3 of the water in the pool
• Monitor weather conditions: Avoid draining during rainy periods
• Consult professionals: Get expert advice before significant water changes

Maintenance Habits That Reduce Risks

Consistent maintenance is your best defense against most fiberglass pool problems. Test and balance your water chemistry weekly, paying special attention to pH, alkalinity, and sanitizer levels.

Brush the pool surface gently but firmly with the appropriate tools to prevent buildup without scratching the gelcoat. Inspect your pool regularly for any signs of developing issues.

Key inspection points:

• Cracks or chips in the gelcoat
• Unusual water level changes
• Discoloration or staining
• Soft spots in the pool floor

Warranties and Choosing the Right Manufacturer

A comprehensive warranty offers peace of mind and protection against manufacturing defects. Look for warranties that cover both the structure and the surface finish, offering extensive long-term protection.

Reputable manufacturers use high-quality materials and proper lamination techniques to create durable pools. Ask potential suppliers about their manufacturing process, including the types of resins used and their quality control measures.

Quality indicators to look for:

• Multiple layers of fiberglass
• Vinyl ester barrier coats
• Hand-laid rather than chopped fiberglass
• Proper curing processes

Planning Your Next Steps

While fiberglass pools can develop certain issues, most problems are preventable with proper installation, regular maintenance, and quality manufacturing. The benefits of fiberglass, including durability, low maintenance, and smooth surfaces, make it an excellent choice for many homeowners to have a long-lasting pool that continually can pass inspections.

If you’re considering a fiberglass pool, focus on finding a quality manufacturer and understanding proper care techniques. Pool Brokers USA offers a selection of premium fiberglass pools designed to minimize common fiberglass pool problems through superior construction and materials.

Our team can help you understand what to look for in a quality pool and how to maintain it properly for years of trouble-free enjoyment. Request a Quote today to learn more about our selection of high-quality fiberglass pools.