How Thick Do Concrete Walls Need To Be Underground

The block wall is built with rebar and all services in place.

How thick do concrete walls need to be underground.

While poured concrete can work just fine for the foundation and the floor concrete blocks stacked and coated with a thin layer of fiber reinforced. As soon as you go higher or have greater depths of soil pushing against the wall you need to increase the thickness to 10 inches. Understanding the basic requirements of underground or basement wall construction helps to attain durable basement walls with minimum maintenance. This could cause condensation issues within the walls and other areas of the home.

For flatwork such as slabs on grade and driveways a minimum thickness of four inches is required but increasing the thickness to five inches can add nearly 50 percent to the load bearing capacity. The slab can be a square or rectangular so long as the minimum depth and surface area requirements are met. As an alternative concrete blocks are often used. Disadvantages of underground homes.

Condensation issues humidity levels are generally higher in underground homes. In general poured concrete basement walls that are 8 feet tall or less and have no more than 7 feet of soil pressing against them from the outside function well at a thickness of 8 inches. When a taller wall or a higher level of soil or both come into play the thickness should increase to 10 inches. Poured concrete foundation walls that are less than 8 feet tall and have soil outside that is 6 or 7 feet deep against the wall can often be 8 inches thick and function quite well.

You ll need to consider incorporating more insulation to prevent condensation from intruding and eventually leading to mold and mildew issues. A good rule of thumb is to have a minimum of about 3 0 3 5 cubic yards of concrete mass to serve as your safe room base. The weight and pressure of the earth will obviously put an enormous strain on the walls and roof of an earth sheltered home which is why concrete makes an excellent choice for a building material. Precast walls in order for a concrete room to effectively resist high winds and flying debris most rooms built with precast concrete walls rely on 12 to 16 inch thick blocks.

Any plumbing or electrical service must be in place and tested before the concrete is poured into the forms. To keep the house and the room from being sucked into the air during a tornado large footings that work like anchors are added to the walls to hold the room in place. For a 4 thick slab this equates to about 250 300 sq ft of surface area.