With the excitement of a new detached structure, any setbacks can be discouraging. There are a variety of reasons why construction can be delayed, such as permitting challenges, supply shortages, and unpredictable weather.
While your builder cannot predict the weather, they can take steps to avoid damaging the integrity of a freshly poured concrete slab.
With rain in the forecast, most builders will consider rescheduling the installation to a day without rain because it can affect the strength of the concrete as it cures. As the necessary water is already carefully measured and added, any more moisture can cause damage.
While a little rain on the slab is okay, in fact it can help by providing hydration for curing, a downpour can harm the surface of the slab or weaken it all together. Rain twelve hours after the pouring should not be cause for immediate concern, as the concrete has set, however it should still be inspected for potential issues.
What Does It Mean To Cure?
Curing of concrete requires a specific amount of moisture, temperature, and time to ensure that the final product is safe and aesthetically pleasing. Curing increases the strength of the final product by helping to protect the slab from future cracks that can impact the integrity of the structure.
Before carpentry can begin, the concrete needs to cure for 2-3 weeks depending on the weather, temperature, and humidity.
While this may seem unnecessary, this timing is vital to having a garage that lasts decades to come. Most of the garages torn down are due to concrete issues including settling, severe cracking or scaling of the concrete.
Washed Out Concrete
When rain occurs, dependent on the amount, surface damage is most often the result. Streaking can occur if the concrete is colored.
Heavy rainfall, on the other hand, can wash out some of the concrete that has been accurately measured and mixed, creating a softer consistency, decreasing the integrity and strength of the final product as it exposes the aggregate.
Large amounts of rainwater also present the risk of contaminants entering the mix, also jeopardizing the cement.
Concrete exposed to an abundance of additional moisture is at a greater risk of cracking due to the uneven surface created.
As additional water enters the cracks, the foundation will weaken over time. The reality of cracking is quite common; however, it is important to monitor and correct if necessary. Your structure will experience a degree of settling; therefore, it is important for the concrete to be strong enough to weather that process.
If possible, push the excess rainwater off the edge of the slab, do not attempt to mix it into various areas of the concrete, in efforts to avoid potential problems.
The peeling or flaking of thin layers on the surface of the concrete is known as scaling. This often occurs when it experiences a period of freezing and thawing before it has cured.
While the damage from scaling may not be evident at first, the more traffic and stress put on the slab, the more the concrete will flake.
If surface cracks/flaking are not addressed and corrected, this can lead to the spalling of the concrete, thus weakening the slab over time.
To ensure that your structure lasts for decades, it is important that your builder take the necessary precautions to protect the investment in your new structure.