Granite crack repair epoxy vs resin

Granite Repair: Epoxy Versus Resin – Significant Differences And Recommended Uses
When it comes to repairing cracks in granite, whether to use epoxy or generic resin is critical as it will determine how long a repair will last, whether the structure remains sound and how attractive the repair looks. Many homeowners and stone restoration professionals are confused by the differences between these materials since epoxy is a subtype of synthetic resin. The two materials, however, react very differently to the natural stone granite. The following guidance will provide details about how the two materials differ, the advantages and disadvantages of both and how they can provide targeted, long lasting granite repairs.
Core Definitions
Resin (in this case) is simply a generic term for viscous polymer materials that become solid after curing (or hardening). There are different types of resin – polyester, polyurethane and epoxy. In the context of granite repair ‘resin’ generally means polyester resin which is the most common type of low cost alternative to epoxy. Epoxy, on the other hand, is a two-part (resin + hardener) high performance resin system with a unique chemical structure that has cross-links. This system of create structure creates extremely strong adhesive bonds between the granite and epoxy as well as very strong structural reinforces to deep/running/cracks in the granite surface; thus preventing cracks from reopening under pressure.
1. Strength & Structural Bonding
Compared to polyester resin, epoxy has a far superior amount of:
a.) tensile strength
b.) shear strength
c.) shrinkage during curing (minimal compared to polyester resin)
d.) chemical cross-linking creating a very stable/more rigid molecular structure that tightly bonds with densely packed granite pores, and
e.) providing structural support to deep/running/cracks in granite surfaces when pressure is applied.It does not provide structural support and is appropriate for surface-level, non-load bearing surface cracks.
Durability & Resistance to Environmental Elements
Epoxy- Good resistance to UV light, moisture, household chemicals, heat and abrasions. Will not yellow, fade or soak-in therefore maintaining a consistent performance for high traffic kitchen countertop, bathroom vanities and outdoor granite surfaces. If applied correctly, repairs are long lasting and can last for a few decades.
Polyester Resin- Little resistance to UV light or chemicals. This system will quickly turn yellow when exposed to direct sunlight, will be destroyed when exposed to acidic or alkaline cleaning products and will absorb moisture over time. Repairs can crack, peel or discolor within a one to three year period, especially for exterior or heavy-use granite.
Curing Performance & Workability
Epoxy- Needs to be mixed exactly at a 1:1 or custom mixing ratio and must cure completely from twelve to twenty-four hours. Because of the adjustable viscosity, epoxy can penetrate very well into both fine and deep cracks in granite. Also, slow curing gives enough time to trim and apply color with precision, allowing for a seamless appearance.
Polyester Resin- Cures quickly and is simple to operate with no specific mixing ratio requirements; fast cure time increases shrinkage and creates secondary small cracks as a result; low viscosity results in easy flowing and very poor filling effects on deep cracks, resulting in very poor repair layers.
Aesthetics & Colour Matching
Epoxy- Very limited colour base options available at this time but offers the ability to create custom blended pigments.An epoxy cured finish is a clear high gloss with a natural granite finish, and gives invisible repairs for high quality granite. Polyester resin is available in multiple pre-mixed colors to quickly match color; however, it is yellowing and may detract from overall appearance of granite surfaces making it inappropriate for visible high quality stone surfaces.
Cost
Epoxy has higher material and labor costs because of strict work standards and long work cycles, but in the long run epoxy is the most cost-effective solution for permanent repairs.
Polyester resin has low initial expense and fast build, but is not the best solution for temporary repairs to hiden granite surfaces or for granite surfaces with low stress placed upon them.

What epoxy or resin do you use for granite repair?
When to choose epoxy:
– for deeper, wider, or structural cracks on countertops, floors, or granular granite.;
– for outdoor granite that is subject to UV, rain, and freeze.
– for high volume use and constantly cleaned granite, such as kitchen or commercial areas;
– for permanent, invisible, high quality restoration of granite or natural stone
When to choose polyester resin:
– for shallow, fine, non-structural means for repair of a single surface crack.
– for hiding granite in low visibility and low stress areas;
– when you have limited funds for a temporary repair that may need permanent repairs at some point in time you will want to use epoxy for granite repairs.

Final Conclusion
For professional permanent granite repair, epoxy will be the first choice for strength, longevity in the weather, and aesthetics, whereas, polyester resin will serve as a short-term, low cost means of repairing small and/or low impact damage to granite. Consider using epoxy for visible, structural, or high use to avoid multiple repairs and/or secondary stone damage to granite.

FAQs
Q. Is epoxy better than resin to repair all granite?
A. Yes for all structural and permanent repairs of an epoxy vs. resin’s use for small temporary means to repair granite. Polyester resin is for shallow, temporary fixes because of poor durability and brittle nature of resin products.

Q. Will epoxy turn yellow when used on granite?
A. High quality, stone specific epoxies formulated with UV resistors should not yellow for many years, while poly resins will yellow quite easily when used outdoors.

Q. Can I Use resin to fix cracks from kitchen granite countertops?
A. No; kitchen countertops take a great deal of use, abuse, chemicals and thermal fluctuations; therefore only epoxy will give you dependedable and proper long-term structural repairs.