Dealing With Ambient Conditions When Placing Concrete Toppings
What is usually done when a layer of concrete in a house, building or driveway gets worn out? Well according to concrete experts a concrete topping is placed, which is defined as the process of creating new layers of high-quality, high-strength concrete over the worn-out concrete layer. However, laying out concrete topping should also take into consideration the current weather conditions, because this may affect the new layer’s strength. Read more to find out.
Placing Concrete Toppings During Hot Weather
When placing premixed concrete toppings, construction experts stress that these toppings are often subject to certain practices and conditions depending on the weather conditions. For example, when the weather is very hot, a lot of emphasis is focused on reducing moisture loss from the placement, and properly managing concrete setting times.
The factors that contractors and concrete suppliers generally consider before placing concrete toppings are aplenty. These include construction planning, concrete mixture design, base slab conditioning and more. Perhaps the simplest procedure when placing concrete toppings during hot and humid conditions is by working in stages – from pre-placement to placement and post-placement (which is not only good for the concrete topping, but also for the workers who would otherwise be exposed to the sizzling temperatures!).
Placing Concrete Toppings During Chilly Weather Conditions
When placing concrete toppings during chilly (or even freezing) weather conditions, greater importance is stressed on the need to prevent early freezing, as well as in managing temperatures during the curing process to enhance the strength development of concrete.
Most construction experts say that the concrete base slab must be maintained at temperatures of at least 40 F during the placement and curing process to prevent early freezing and to enhance strength. And if possible, the experts stress that it would be best to heat the base slab if only to prevent freezing, as well as lead to improved curing conditions.
And, when placing concrete toppings during freezing conditions, keep in mind your Boy Scout motto when you were a kid (or when your contractor was a kid), and that’s “Failing to be prepared is preparing for failure!
This means that you must never place concrete on frozen ground or onto snow or ice, as the frozen surface may settle when it thaws and therefore crack the concrete. When the ground is very cold, the concrete will absorb the coldness and set more slowly.
Placing Concrete Toppings During Rainy Weather
Perhaps the toughest weather to place concrete toppings would be during rainy, stormy conditions. The good thing is that under most circumstances, concrete toppings that are exposed to rainwater are not automatically damaged, especially if excess rainwater is removed before finishing.
According to guidelines published by Cement Concrete & Aggregates Australia, if the concrete surface appears or looks wet, the excess rainwater may need to be removed, if only to allow for the finishing process to continue. This is because the additional rain may increase the water-cement ratio, which could result in a weaker surface, lower strength and increased shrinkage.
And, before you schedule any concrete delivery during rainy weather, prepare a lot of plastic covering so you could place it over the freshly-topped concrete to protect it from the elements!