Cause Of Concrete Patio Deterioration Below Siding

Concrete can deteriorate for a variety of reasons and concrete damage is often the result of a combination of factors.

Cause of concrete patio deterioration below siding.

In the phone interview the concern is over the distance to the siding. When the lower edge of the siding is below grade moisture can be wicked up behind the siding and insects and vermin can enter the building unobserved. Corrosion of reinforcing steel is the most common cause of concrete deterioration. High strength concrete mix designs that incorporate air entraining admixtures yield the best defense against freeze thaw damage.

High humidity and moisture is prevalent in basements because the concrete walls are surrounded by moist soil. What s been discovered is a surface delamination in the concrete floor. A diyer or a novice painter might attempt to achieve a cleaner look by caulking the siding nails but the nail is guaranteed to push the caulking material out within a few months. The following summary discusses potential causes of concrete deterioration and the factors that influence them.

30 50 and 100 sieves resulting in a sticky or tacky concrete that can become more easily sealed when floating or finishing it at any early age. I have always worked with the notion that a concrete patio should at minimum have a least 2 of clearance from the last row of siding. Concrete absorbs water into its pores. Homeowners power washing their concrete can often cause accidental damage either to their home or themselves.

When the water in the pores freezes it expands causing scaling and delaminations. This natural settlement causes excess mix water and entrapped air to be displaced called bleeding and the lighter materials migrate toward the surface. In addition to concrete damage power washing horror stories include stripping paint off of houses ripping off siding and shingles damaging wood decks destroying car paint jobs and even causing serious injuries. A frequent reason behind a darkened concrete appearance is the addition of calcium chloride to accelerate the setting time of concrete see photo 1 especially when calcium chloride dosages approach 2 by weight of cement.

Water saturated concrete combined with temperature cycling above and below 32 f 0 c. How do delaminations happen. Corrosion of embedded metals fig. I have a client that would like me to come over and evaluate his patio.

Siding nails should not be caulked another item that needs room to play is siding boards themselves. In preparing for thi. Inadequate mixing after addition of calcium chloride makes the concrete color even more irregular or blotchy. When fresh concrete is placed and compacted the solids cement and aggregate settle.

An excess amount of entrapped air held within the concrete by a high percentage of material passing the 600 µm 300 µm and 150 µm no. Attribute blistering to three principal causes.