Every building is only as strong as its foundation—and steel structures are no exception. Concrete is obviously the favorite material for metal building foundations, and it might seem like pouring a slab is a simple process. In fact, some people decide to take on this task themselves to prepare their site for the erection of a steel structure. However, there are several factors that can make it inadvisable for a property owner to pour a slab without doing proper research and understanding the ramifications of this construction process.
#1 Pouring without a Plan
Even if a property owner knows what size they want their building to be or has an idea of the preliminary placement of anchor bolts, it’s a mistake to pour a foundation before engineering drawings are complete. In fact, a foundation needs to be designed based on the specific soil type, climate, and local building requirements for a given location. The company working to create engineering plans for a prefabricated building may not be familiar with local conditions that could impact the foundation. In this case, they may need to collaborate with a local engineer to ensure that the slab is up to the task. For example, a structure built in a very cold region with a frost line needs deeper footings than one built in a warm environment.
#2 Not Making It Tough Enough
A metal building that will be used as a woodworking shop or a storage space for boxes of unused items may be fine with a standard foundation. But if a monster truck or an RV is being parked inside, that’s a lot of weight! The slab will need to be significantly thicker and made with appropriate materials and reinforcement to withstand more pressure than a standard 4” slab with 2500 PSI strength. This will impact the initial price to pour the slab, but it will help the building last much longer. The engineering plans should specify what type of reinforcement is needed, whether rebar and welded wire, steel fiber, or other options.
#3 Curing without Adequate Ventilation
What about pouring a slab after the structure is already in place? That’s a situation that might come up during cold weather when it might seem to make sense to protect the curing concrete from winter storms and the freezing temperatures. While it’s possible to pour concrete after erecting a building, this can lead to issues with condensation. That’s especially true if heaters are used to artificially speed up the curing process. As concrete dries, a huge amount of moisture is released into the air. When there isn’t adequate ventilation, the condensation on the interior of the building can drip back down onto the concrete as it cures, causing significant problems with proper drying. The best option is to erect a steel building on a slab that has already been poured and dried. The next best option is to ensure there is adequate airflow to the outside—even if that means temporarily removing some of the steel panels and leaving windows and doors open.
Since steel buildings are designed to last for many decades, it’s essential to have a foundation that will stand the test of time, environmental conditions, and heavy duty use as well. Start your planning off right by consulting with our engineers and designers. Get a free quote today.