Concrete Spalling

Concrete spalling is often caused by improperly placing the rebar or wire mesh when pouring the concrete. If the rebar is to close to the top of the concrete slab, as water soaks into the concrete it will start to corrode the rebar. This will cause the rebar to expand, weakening the concrete above the piece of rebar.

Concrete Spalling

Concrete Spalling

If you look left of the blue line, you will notice there is a crack starting to form, this crack is right above a piece of rebar corroding. When we tap the concrete with a hammer we hear a hollow sound. To repair this we have to break out all the loose concrete, cut 90 degree edges, pressure wash & clean the rebar, and apply a non-shrink repair mortar.

Spalling Concrete Cause By Corroding Rebar

Spalling Concrete Cause By Corroding Rebar

Right after we start to chip out the bad concrete a piece of rebar started to stick out. This was the main cause of the damaged concrete. It is very important to place rebar and wire mesh at the proper place when pouring concrete.

Spalled Concrete Area Chiseled Out

Spalled Concrete Area Chiseled Out

Concrete Resurfaced & Stained

Concrete Resurfaced & Stained

After the concrete was chiseled out we applied Miracote RM 2 and then finished of the spalled concrete repair by resurfacing the area with Miracote MPC, and then applied a grey stain to match the bricks.

Tinted Concrete Sealer

A great low cost alternative to acid staining concrete is to use a tinted sealer.

Tinted sealers are opaque, so any exterior surface stains that can not be removed from the concrete will be completely covered up with a tinted sealer.Tinted concrete sealers also waterproof the concrete which helps prevent surface spalls. They can be used on any exterior concrete surface.

The most important part of having a tinted sealer last, is prepping the concrete surface before applying the sealer. We always acid etch and pressure wash the surface so the sealer will have a rough surface soak in and bond to. The sealers don’t last forever, they typically have to be re-sealed every two years depending on traffic.

There are over 50 colors to choose from when using a tinted sealer and can have a matte finish or gloss finish.

Here is a photo of a recent concrete patio we sealed with a tinted sealer.

Concrete Patio Sealed

For more information check out are website at MVL Concrete.