Get matched with top structural engineers in Bay, AR

A 4-inch-thick concrete slab can support around 4,000 pounds per square foot if a contractor reinforces the slab with rebar, while that same slab without reinforcements will support closer to 1,000 pounds. For the purposes of a patio, 4 inches in thickness without reinforcement should suffice unless you’re installing heavy kitchen equipment or a hot tub on it. In those cases, reinforcing your slab and sticking with 4 inches of thickness should provide plenty of strength.

Although the two terms are closely related and often used interchangeably, pier and beam foundations and crawl spaces are different things. A pier and beam foundation is made up of concrete piers and wooden beams and creates a space under the home known as a crawl space. There are several types of foundations that create crawl spaces, often collectively known as “crawl space foundations,” but the crawl space itself is separate from the foundation. 

In framing, studs are placed at 16-inch intervals to coincide with the typical spacing of wall materials such as drywall or plywood. This spacing is called "on-center" and is necessary for maintaining structural stability and efficient use of materials. The 16-inch spacing also helps to distribute the weight evenly across the building's structure. For those looking to cut material costs and improve energy efficiency, 24-inch stud spacing can be employed through a method called "advanced framing". This requires careful planning and adherence to local building codes to ensure structural integrity.

The primary reason homes have crawl spaces is so the foundation can reach down below the frost line to avoid dangerous soil movement and structural damage when the ground freezes. They’re more popular in colder climates where the ground freezes down to a few feet, and slabs are most popular in warmer areas where there is no frost line. Crawl spaces also provide a space for utility lines to run where they’re at less of a risk of freezing.