If you have a large kitchen then you will likely have to have a seam in your granite countertops. This goes for granite, marble, quartz as well as all other types of countertops.
The only exception is solid surface countertops because the seams in countertop surfaces like Corian will be sanded down and almost impossible to see.
For all other countertops, there is likely going to be a seam.
You can be in control of where your seam is placed before your countertops are even fabricated but here are some things to consider.
I prefer the sink center for any seam in my personal home. This is due to the length of the seam. It is supported by a sink and the cabinet and the epoxy that holds the seam together is strong and supporting also.
If a sink center seam is not an option I will opt for my seam a few inches to the right or left of any right-angle corners.
Pro Tip: Never put a seam above a dishwasher. This area above the dishwasher gets really warm and could also be moist causing the seam to eventually weaken and break.
People ask me often how to avoid a granite seam. The only way to avoid a seam in your granite is to design your kitchen around the size of the slab you are working with.
This simply means visiting your local countertop fabricator before your cabinets are ordered. You should always have your countertop color chosen when choosing your cabinets for design reasons so why not go ahead and reserve your slabs in the process.
When you have chosen your slabs you will design your cabinets around the length of your slab to avoid having a seam. You will work with your fabricator and your cabinet maker to accomplish this. If you are going to have an island you will choose a size that prevents having to use two slabs of stone which means keep it smaller than your slab.
When choosing your main countertop runs for your kitchen be sure to consider the size and width of your slab.
If you have a long kitchen you may need to separate it with an oven cabinet or a stove to shorten the length of the granite needed to cover that cabinet space.
Remember also if you have patterns in your granite such as veins that need to all run a specific way to look good you will have to consider this when choosing the length of cross cabinets that run the opposite of your sink area.
A perfect granite seam always starts with the countertop fabricator you are working with. Always choose a quality fabricator and check out reviews.
It all starts with the fabricator. If your fabricator uses CNC machines to blank out your countertops then you will likely have a better quality seam.
The countertop installer must level the countertops in order to get a good seam. They must have level cabinets to work with so make sure your cabinet installer works to level the cabinets as best possible.
The installer must match the color pigment when using epoxy to glue the two pieces in a granite seam together. Most of the time the two granite pieces are so tightly pushed together that the color in the epoxy doesn't matter much but if not the color must be matched well.
To avoid most issues that involve a granite seam you must choose a quality countertop fabricator that will allow you to be involved through the entire process.
Let's recap some of the information above:
You can have your granite seam redone by having a countertop professional heat up the area and remove the epoxy and then reapply new epoxy. It is best practice to have it removed and then try to have it much tighter and better quality.
Sometimes the countertop professional may opt to remove the pieces and take them to their shop to recut the area which will ensure a tighter less visible seam.
Do not sand your seam or the top of your countertops. This will cause the finish to look etched and when light hits the area you will see dull spots. It is not a great idea to sand the tops of any countertop. There are special tools to do this the right way but it requires a skill that most countertop professionals do not have.
If your granite seam is not properly done it will yellow over time and become an eyesore. Avoid this by following this granite seam guide.