Cracked granite countertop

Q. I had granite countertops installed about five months ago. Yesterday, I noticed the granite had cracked all the way through on both sides of the undermounted sink. What caused this - was it improperly installed?

A. Cracks of this nature can be caused by any number of issues. If the countertop was not shimmed properly this could place undo stress on the top and cause it to crack. 

Another cause of cracking is not having the stone properly rodded when called for. Fabricators will install metal rods under the countertop and in the stone to strengthen the countertop to prevent this from happening. If you can get under the top check to see if there are any grooves where rods have been placed. If the sink was not mounted properly or the sink was too heavy this could also cause it to crack. In my opinion the fabricator is responsible and should try to repair the crack if possible or replace the top.

Dr. Fred

Chief Technical Director

CRACK
A break, split, fracture, fissure, separation, cleavage, or elongated narrow opening, however caused, visible without magnification to the human eye and extending from the surface into the stone, through the gra in, matrix, or vein

GRANITE
A very hard, crystalline, igneous rock, gray to pink in color, composed of feldspar, quartz, and lesser amounts of dark Ferro magnesium materials. Black ’granites’ are similar to true ’granites’ in structure and texture, but are composed of different minerals