Proper Care/Maintenance & Expectations For Your Concrete

The most common question and most common misconception about concrete is, “ will the concrete crack? “ The answer is simple… PROBABLY YES, but this is normal. Especially for our climate in Manitoba. We also know it does crack due to our Manitoba clay and soils. Cracks are a natural consequence of exposure to the elements, and the curing process. There is NO way to prevent or predict when and where a concrete slab may crack, and there is NO minimum grace period or time limitation, a crack may appear within a day of a slab hardening, or after decades of undisturbed, unblemished surface. The trick is not in stopping the cracks, it’s about minimizing their impact.

We ensure that every slab we pour:

  • Begins with a firm wet compacted base.

  • Has consistent and correctly placed and/or anchored steel reinforcement, abundantly and appropriately gauged for the intended use.

  • Is poured with concrete mixed to the correct strength for the intended use.

  • Has enough depth of concrete to support the intended use.

The difference between cracks and breaks:

A crack is a surface blemish only, it does not compromise the originally intended function, shape or grade of the slab. Cracks are unavoidable and are not covered by our 3 year warranty policy. This is consistent with the provincial guidelines set out by construction organizations in Manitoba such as the Manitoba ready mix concrete association ( MRMCA ), and the Manitoba new home warranty program workmanship and material reference guide.  A break is identified by a crack that has either opened into a significant void of ⅜ of an inch or more, or that is accompanied by either vertical or horizontal shifting. If natural wear and tear and exposure are able to exploit a crack into a break, that is a symptom of a defective product.

Information on Concrete Scaling

What is scaling?

Scaling is local flaking or peeling of the surface of hardened concrete as a result of exposure to freezing and thawing while moist. Generally, it starts as localized small patches, which later merge and extend to expose larger areas. Light scaling does not expose the coarse aggregate, whereas moderate scaling exposes the aggregate and usually involves the loss of the surface mortar layer.

Why do concrete surfaces scale?

Concrete slabs exposed to freezing and thawing in the presence of moisture and/or deicing salts can scale. Most scaling is caused by:

  1. Curing is one of the most often ignored fundamentals of quality concrete construction. To maximize the surface durability of concrete, it must be cured properly. Concrete gains strength by the cementitious materials going through a chemical process called hydration. This hydration process requires water and heat to react with the cementitious particles. Once concrete dries, there is no more water for the reaction to take place, so it stops gaining strength. If the concrete is not cured, and the surface is allowed to begin drying during or immediately after placement and finishing, the strength and durability of the concrete surface will certainly be compromised. A concrete surface that has not been cured is also much more permeable, allowing more water into the surface and thus at much greater risk of freeze-thaw damage.

  2. The use of non-air-entrained concrete or concrete with too little entrained air. Air entrainment is required for protection against freezing and thawing damage. However, even properly air-entrained concrete will scale if other best practices for placing, finishing and curing concrete are not followed.

  3. Application of calcium or sodium chloride deicing salts on concrete without adequate strength, air entrainment or curing. Chemicals such as ammonium sulfate or ammonium nitrate, which are components of most fertilizers, can cause scaling as well as induce severe chemical attack on the concrete surface.

How to prevent scaling?:

  1. DO NOT use deicing salts, such as calcium or sodium chloride on the concrete surface, use clean sand for traction or lava grip.

  2. Provide good drainage. Poor drainage permits water or saltwater solutions to stand on the surface for extended periods of time, saturating the concrete. The saturated freeze-thaw cycles are what causes the most damage. ( Scaling is most often noticed near gutter downspout flow lines or other melt-water sources )

  3. Provide proper curing immediately after finishing operations are completed. Curing should be maintained for a minimum of 7 Days ( weather pending ). Most of the common method of curing include; spraying a membrane forming a curing compound on the surfaces.

  4. Protecting concrete from the harsh wet winter environment. It is important to prevent newly placed concrete from becoming saturated with water prior to the start of winter freeze-thaw cycles.

How do I care for my concrete in the winter?:

You can help maintain concrete by shoveling the snow from your driveway, sidewalk, and steps. By keeping the snow cleared, there is less chance that it will compact down - eventually freezing into the surface that accelerates the freeze/thaw cycle. The less number of times that water enters concrete and freezes, the less likely that it will become damaged.

Avoid using deicing chemicals:

Using deicers on your concrete driveway in the winter can cause surface damage; primarily scaling and spalling, by forcing the thawing and refreezing cycle of moisture. Products containing ammonium nitrates and ammonium sulfates are especially harmful because they will actually attack the concrete chemically. Rock salt ( Sodium Chloride ) or calcium chloride will do less damage, but they can harm the vegetation and corrode metal.

NOW OFFERING

We at Jerry’s Concrete are providing the service of selling sealer to our customers. You can also purchase sealer(s) from Brock White, Specialty Construction, Home Depot, ETC. We are also selling Lava Grip ( traction grip ) to our customers. This can also be purchased at Canadian Tire, Lowe’s, Walmart, Home Depot, ETC

Please phone the office for prices 204-668-9699/204-661-4444