Water curing a concrete slab foundation is very important and often overlooked by many home builders. Some people may have never heard of it before or even seen it in practice. Water curing is the process of keeping concrete moist so that the hydration process can occur effectively. To fully understand, we need to look at the hydration process of concrete in quick detail.
Concrete is made up of Portland cement, aggregate, and water. When we mix all of these ingredients together, they begin a chemical process called Hydration. I know I am starting to get pretty Nerdy on you, but in short concretes' composition is fairly complex and simple at the same time. One of the most important ingredients in a mix is actually Water. When Water is introduced the chemical reaction begins and the concrete begins to Hydrate, or as many people say Harden.
As concrete is poured (Fun Fact: it is actually called "Placing" concrete) the water in the mix begins to evaporate from environmental conditions, as well as during the Hydration process. If the water is allowed to evaporate too rapidly, this can cut off the Hydration Process and the concrete will not develop to its designed structural strength and durability.
If we look at a concrete slab poured for a new custom home in the middle of Summer, the water evaporates very quickly leaving the concrete dried out. When this happens the chemical process actually slows down and in some instances can even stop. The strength at this point is not near to what it was designed for. Most times concrete cures to almost 70% of its designed strength in the first 7 days. However, if it is left to dry out excessively, the intended design strength may never be reached. Another bad side effect of loss of moisture is, concrete will be more prone to shrinkage cracking.
So all chemistry aside, its pretty simple! Make sure your Builder is watering your slab to help minimize issues down the road.
