Cracks in the floor of a concrete garage can be a cause for concern, but it's important to know when to worry and when to take action. A qualified and licensed professional should be consulted to classify the severity of the crack and investigate the cause. Crust-forming cracks usually occur during the concrete stamping process, which is a way to add texture or pattern to concrete surfaces. Cracking cracks after hardening can result from excessive flotation that tends to attract water and cement to the surface, leading to weak concrete subject to high shrinkage stresses.
Older homes and houses built on expansive soils tend to have more cracks, but even if they do, it's important to determine if they are significant or just normal for age and geographic area. To maintain small cracks for telegraphy through ceramic tiles, most tile contractors now apply a crack insulation membrane on top of the slab before applying the thin-layer mortar. This expansion process can take 5 to 20 years before cracking eventually leads to the failure of the concrete structure. If the cracks are stable and less than ¼ inch wide, you can repair them with a flexible sealant made for concrete, such as Sikaflex Concrete Fix.
Only if you see a crack in the floor slab that continues in the foundation wall where the crack meets the wall would the structure obviously be involved. The repair of mass concrete structures will depend on the width of the crack, the depth, whether it is idle or alive and on the service conditions of the structure. Although they are almost invisible, it is important to remember that plastic shrinkage cracks not only exist on the surface, but extend throughout the entire thickness of the slab. In cases such as a new building with 15 beams 20 to 15 meters long that have cracks 300 mm vertical distance around the beam over its entire length, it is important to take action.
Pouring concrete when conditions are too high (above 77 degrees F) increases the chances of shrinkage cracks and makes the slab weak. It is essential for homeowners and buyers alike to understand when cracks in concrete are serious and when they are not. Consulting a qualified professional is key in determining if there is cause for concern and what steps should be taken for repair.