"…even with the best floor designs and proper construction, it is unrealistic to expect crack-free and curl-free floors…” 302.1R-04: Guide for Concrete Floor and Slab Construction.
The way hairline cracks were made to look attractive in this 8,000 ft2 remodel for a low cost retail store in Irving, TX was a prime example of how economical and yet striking an acid stain floor can be. After a few days of cleaning and prepping the floor, we applied a kona brown stain to it that created this rich patina which varies in color throughout the floor; even the cracks in the floor add to the beauty. The owners loved both the color and the price. After an experience with cracks in the concrete of my home, it is amazing to see how hairline cracks can become an asset to any décor and not a detriment.
In 2008 when my husband and I moved into our brand new house we were elated! Everything pleased us down to the new smell of new concrete in our ample basement. However, as we settled in during the first year and the house continued to settle around us we noticed tiny hairline cracks appearing in different areas of our home.
The most important thing we learned was that hairline cracks are not usually cause for concern since they were considered as non-structural cracks.
Structural Cracks and Non-Structural Cracks
In an April 2011 article on Plant Engineering & Maintenance (PEM) Drew Robb helped me to understand the difference between structural and non-structural cracks. He quoted John Dunterman, who worked at Wiss, Janney Elstner Associates, which is an engineering firm. According to Dunterman, it was important to "accurately assess" the cracks to figure out what category they fell under before one went about finding the "right repair solution."
Concrete Cracks and their Causes
There is a wide assortment of information available about concrete cracks available on the internet. However, for a lay person like me, the site that broke it down best was eHow home. A short and readable piece written by Lon Quist, and eHow Contributor made an easy list in his piece "Causes of Cracks in Concrete". According to him the type of concrete used and type of crack that occurred should determine the repairs to be done. Some types of cracks that can occur are:
* Random Cracks-cracks spread in multiple directions
* Settlement Cracking-when the ground has not been readied properly.
* Heaving Cracks-caused by fluctuating temperatures.
* Hairline Cracks
Hairline Cracks and why not to worry
All in all, hairline cracks were nothing to be worried about. Another site that put my fears to rest was ConcreteNetwork.com a type of forum where all questions related to concrete can be answered. A short piece on the site titled "Fixing Hairline Cracks" finally gave me the last bit of information I needed and I set about fixing the tiny cracks after a thorough assessment.