Larry B. Hairline cracks in a concrete slab are rarely a cause for concern. They can be controlled, but not eliminated. A crack in a slab of 1/8 inch or less is typically a normal shrinkage crack and not a cause for concern.
Should I worry about hairline cracks?
Generally, smaller hairline cracks are not cause for concern. These are usually the result of seasonal expansion and contraction of clay soils beneath your house over time, and can be easily patched and re-painted.
What can you do for hairline cracks in concrete?
You can repair hairline cracks in concrete with a grout made of Portland cement and water. Add just enough water to the cement to form a thick paste. Moisten the old concrete along the hairline crack with water for several hours before adding the grout.
What is considered a hairline crack in concrete?
A.: ACI 116R-90, Cement and Concrete Terminology, defines hairline cracks as cracks in an exposed concrete surface having widths so small as to be barely perceptible.
Should I repair hairline cracks in concrete?
These types of cracks do not signify serious underlying issues and are more of a cosmetic issue. That said, hairline cracks in concrete can worsen over time if not dealt with. If deep cracks cover the surface of the concrete, then it might be best to replace the concrete entirely.
What causes hairline cracks in concrete?
What causes hairline cracks on concrete? Both significant structural cracks and hairline cracks are often caused by stress relief. Most structural cracks on concrete surfaces form as a result of pressure and stress. However, hairline cracks can also occur as a result of shrinkage from heat.
Will concrete sealer fill hairline cracks?
To repair the crack, the sealer (or other filler material) needs to penetrate into the crack and fill it completely. Ideally, the sealer has a low surface tension so it readily wets out the concrete and a low viscosity. Keep in mind that materials like epoxy are effective because they wet out the concrete.
Can you repair hairline cracks?
You can repair hairline cracks in concrete with a grout made of Portland cement and water. Add just enough water to the cement to form a thick paste. Moisten the old concrete along the hairline crack with water for several hours before adding the grout. Then smooth it off so it is level with the original concrete.
How do you seal hairline cracks in concrete?
https://www.youtube.com/watch?v=fHysHbXNIYQ
Will concrete sealer fill small cracks?
Cracks up to ¼ inch in width can be filled with sealant. Small cracks here and there that are narrower than ¼ inch are most likely the result of shrinkage as the driveway cured. Flexibility is key to a good sealant.
Does hairline crack sealer work?
4.0 out of 5 starsSeems to work. I used this on a new concrete patio that developed a couple of hairline cracks. It took all day and over 10 applications but seems to have filled the largest crack.