All natural-stone is porous in varying degrees. This characteristic generally makes for a favorable substrate to be bonded. However, stone doesn’t make a very good flat surface until it’s cut and polished. All rock materials loose some of their porous characteristic when polished, but unlike other natural stone, granite is almost non-porous after polishing. This makes it a more difficult material to bond. Never fear, epoxy for granite is here!

There are other adhesives that can be used on granite, but what you use is largely dependant upon how your granite is cut. Is it a floor tile or wall tile? Perhaps it’s a large granite kitchen counter top or a smaller bathroom sink counter.

Mastic glue and general adhesive are typically used with granite tiles. Occasionally a general adhesive will be used to bond a slab to the plywood. Silicone glue is typically used for caulking joints such as between the back splash or sink and a granite counter. Some glue manufacturers have developed silicones designed specifically as granite adhesives.

By far the most common and best type of bond for granite will be an epoxy. It is a complex blend of resins and hardeners. Epoxy is structural glue and when cured this adhesive is a strong as the stone itself. This is of particular importance when working with a slab of granite. The last thing you want is for the bond to fail and a huge, expensive piece of granite to slide off onto the floor. Epoxy glue is used not only for the installation of the slabs, but also used to join two pieces together, such as with two slabs for more thickness, or where two slabs butt up against each other. Again, the importance of the two slabs to adhere to each other is extremely critical.

Granite epoxy is also known in the stone industry as A-B. Part A is a resin and part B is the hardener. Adhesive manufacturers vary the ratios anywhere from 1:1 to as much as 5:1, dependant on the application. As a rule epoxies contain no styrene and is much stronger than other glues. If mixed properly and used to bond granite to granite, as mentioned earlier, the epoxy will actually dry stronger than the granite. The two slabs virtually become one piece, and will perform and break as one. One factor that contributes to the strength of epoxy is the slower curing time it has over other glues. Some view this as epoxy’s nemesis as well, especially if time is of concern. There are available on the market faster setting epoxies that can actually be hard in just minutes. If you don’t work quickly to set the materials correctly, you may not be able to. While it isn’t completely cured, the epoxy is set enough to make it difficult for further adjustments to be made. These quick setting epoxies cost more as well, so if time is not an issue, don’t pursue this avenue.

Epoxy cures transparent, however, all epoxy can be colored with coloring pastes designed for this purpose. Specific paste dyes designed for this purpose should be used to avoid diluting the glue resulting in diminished strength. It is possible to have a custom manufactured epoxy specific for your needs. If you find that there isn’t a product that exists on the market, Adhesive Systems is capable of custom producing a product for you.

For more information about Adhesive System’s epoxy adhesives or having a custom adhesive designed for your application, please contact us at 877.740.1250 x20. You can also send us an email at