How to Store Resin and Fiberglass: Best Practices for Long-Lasting Materials

Storing your composite materials correctly is one of the easiest ways to protect product quality and ensure consistent results during repairs or builds. While fiberglass itself is relatively stable, resin storage requires extra attention—especially polyester resin, vinyl ester resin, and epoxy resin.

This guide focuses on how to properly store these resins and your fiberglass reinforcements so they stay in good condition and ready for use.

 

1. Why Proper Storage Matters for Resin

Resins can be affected by temperature changes, moisture, and exposure to air. Over time, improper storage may lead to thickening, separation, contamination, or shorter shelf life.

Proper storage helps maintain:

·      Consistent viscosity

·      Reliable curing performance

·      Longer usable life

·      Cleaner, more predictable results

 

2. How to Store Resin

Keep the Containers Sealed

Always close the lid tightly after each use. Exposure to air can introduce moisture or contamination.

Store in a Cool, Dry Place

A stable, moderate-temperature environment helps maintain the resin’s consistency.

Avoid areas with heat sources, direct sunlight, or drastic temperature swings.

Good storage locations:

·      Shelving in a climate-controlled workshop

·      Indoor storage cabinets

·      Temperature-stable garage areas (away from sunlight)

Avoid:

·      Attics

·      Outdoor sheds

·      Hot vehicles

·      Directly on concrete floors (can transfer moisture/temperature fluctuations)

Keep Away From Direct Sunlight

Sunlight can warm the container and affect the resin’s stability over time.

Store it in a shaded, enclosed space.

Avoid Storing Resin Near Moisture or Chemicals

Moisture can interfere with how the resin performs.

Keep containers away from water sources, damp areas, or strong chemical fumes.

Label and Rotate Stock When Possible

Place newer containers behind older ones to ensure you use older resin first.

3. How Long Resin Typically Lasts (General Guideline Only)

Resins are best used within their recommended shelf life when stored correctly. If a container has been stored for an extended period, check its appearance and consistency before use.

 

4. Storing Fiberglass

Fiberglass is more stable than resin but still benefits from correct storage.

Keep Fiberglass Covered

Leave it in its original packaging or rewrap with plastic to keep out dust and moisture.

Store Rolls Horizontally

Storing rolls on racks helps maintain their shape.

Store Flat When Possible

Flat storage prevents unwanted bending or warping. If vertical storage is needed, support the fiberglass along their full height.

Avoid Stacking Too Much Weight

Place protective layers—such as cardboard or foam—between fiberglass if stacking is necessary.

 

5. General Handling and Storage Safety

·      Wear gloves and protective clothing when handling fiberglass and resin.

·      Keep your storage area clean and ventilated.

·      Avoid placing heavy items on top of resin containers or fiberglass rolls.

·      Keep all materials off damp floors and away from water sources.

 

6. Common Storage Mistakes to Avoid

·     Leaving resin containers open or loosely sealed

·     Storing materials in direct sunlight or locations that become very hot or very cold

·     Keeping resin near heaters, open flames, or heat-generating tools

·    Allowing fiberglass to sit uncovered and collect dust or moisture

Final Notes

Proper storage plays a key role in keeping your resins and fiberglass materials in good condition. With a few simple habits—stable temperatures, sealed containers, clean environments, and covered materials—you can maintain consistent performance and be ready for your next repair or build.

If you need additional product guidance or storage recommendations, True Composites offers resources and materials to support your projects year-round.