How to Successfully Repair Cracks in Concrete Miami Roofing

miami roofing cracks

Cracks in concrete commonly happen during construction. The causes for these cracks vary as well as the resulting cracks. They may be caused by mixing too much water or extreme heat that affects the surface of the concrete.

Several methods are available to repair cracks in concrete Miami roofing. You just have to choose the best solution for the cracks.

Evaluating the Cracks

The first step is evaluating whether the crack is active or dormant. Active cracks move and grow such as those produced from continuing foundation settlement. Dormant cracks do not grow, and future movement is not anticipated.

Generally, active cracks need flexible materials for repair and special considerations for future movements. Dormant cracks can use either flexible or rigid repair materials.

The nature of the crack must also be considered, which are typically divided into three categories: Those that require repair to restore structural integrity; those that require sealing and lastly, those that require improvement in appearance only.

Different Repair Techniques

After taking these steps, you are now ready to make actual repairs on the cracked concrete. Some of the repair methods are:

  1. Stitching and Doweling. Stitching works by drilling holes on opposite sides of the crack and installing metal staples with short legs across the crack. Doweling works similarly but instead of using U-shaped metal staples, straight steel dowels are used and placed at a 45-degree angle on the length of the crack.
  2. Dry Packing. This is ideal for dormant cracks as it is very economical. It consists of opening the crack to a certain depth and width of around one inch. A commercial bonding agent is poured on the expanded crack topped by low-water content cement mortar. Tamping the mortar forces it to enter the pores of the concrete for that tight and durable repair.
  3. Polyurethane Injection. This repair method could be used for wet and leaking cracks. The primary purpose of this type of repair is to stop water leaks. A reactive resin is injected into the crack, which when combined with water forms an expanding gel that effectively seals the crack.
  4. Epoxy Injection. It bonds cracks together and brings back concrete integrity. The method involves pressure-injecting epoxy on holes drilled on the concrete at regular intervals. The crack must be dormant and not leaking for epoxy to work properly. The presence of water reduces the effectiveness of epoxy.
  5. Routing and Sealing. This repair involves enlarging the crack and filling it with sealant. It is one of the most economical ways to repair cracks, whether they are fine or large. It can seal both dormant and active cracks, depending on the sealer used and sealant reservoir.

Causes of Cracks in Concrete Atlanta Roofing

concrete roof crack in atlanta roofing

Concrete cracks are normal occurrence but often misunderstood by homeowners. In fact, cracking is one of the most common causes of complaints in the construction industry. While most concrete cracks are not dangerous and do not pose a serious structural threat, they are, nevertheless, unsightly. In some extreme cracking cases, they negatively affect the durability and serviceability of the structure.

Recognizing and repairing concrete roof cracks is top priority, especially for people living in Atlanta, where potential damage to structures is a strong probability from earthquakes. There are different types of cracks in concrete Atlanta roofing, and each one has its own causes. Some of these are:

Crazing Cracks. These look like shattered glass or spider webs on the surface of the concrete slab. The cause of this type of crack is the rapid evaporation of water from the top of the concrete slab. While they may not look good, crazing cracks do not affect the structural integrity of the concrete roof slab. However, since the cracks are very fine, they cannot be repaired.

Expansion cracks. Concrete slab, similar to other materials, expands under hot weather. The expanding slab pushes against neighboring materials such as an adjacent slab or wall. If these materials do not give in to the pressure, the slab will crack from force.

Overloading Cracks. Putting too much weight on top of a concrete slab roof could cause cracks. While concrete is very strong and durable, it still has limits on the load it can carry. Too much load placed on top of concrete could crush it. While the weight may not be enough to pulverize the concrete, it could cause cracks to appear. The compressive strength of concrete is greater than its flexural strength, hence it bends under the weight.

Plastic Shrinkage Cracks. The most common cause of cracks is probably plastic shrinkage, which can occur a few hours after the slab is poured. This crack usually happens during hot weather. Having excess water in the mix with concrete is the cause of this crack. Water occupies space in the slab and forms part of its size. When water evaporates during curing, the slab becomes smaller. The shrinking creates stress on the concrete slab, which ultimately cracks to relieve the tension.

Vertical Cracks. These are caused by concrete settling around reinforcing bars. The cracks are caused when the concrete near the top partially sets while the rest of the concrete are still settling. Applying vibration to the concrete can prevent this crack from forming.