That s because a footing that s too wide and not thick enough will experience a bending force that could crack the concrete.
How thick should a poured concrete wall be.
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.
When a taller wall or a higher level of soil or both come into play the thickness should increase to 10 inches.
There are two forces which act primarily upon foundation walls.
Several factors determine the cost of a poured concrete wall such as the dimensions of the wall the thickness its height and its length the number of reinforcements present and the quality and type of concrete used.
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.
The one force is a downward force gravity load created by the load placed upon the wall.
This can add several inches to the wall s thickness dimensions and can vary depending on the severity of exposure soil type and reactivity etc.
However let s compare two 8 inch thick walls.
So taller walls in heavier soils should be made thicker or with stronger concrete.
For plain concrete walls which are walls without or with little reinforcement 7 1 2 inch thickness is adequate.
As a material concrete is usually divided into concrete blocks and poured concrete walls.
Increasing the strength of the concrete mix or the thickness of the wall increases the wall s capacity.
So for example a 32 inch wide footing under an 8 inch wall would need to be at least 12 inches thick.
The thickness of concrete is an important factor in load bearing strength but to conserve resources and avoid over building other factors are also taken into consideration.
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.
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.
In addition to basic structural requirements wall dimensions generally member thickness are also affected by the required minimum reinforcement cover.
Poured concrete wall average cost.
Structural concrete work is planned to bear loads or hold weight but transfer the weight to the soil base beneath the structure.
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.
How thick should a concrete retaining wall be.
The other force is a sideways or lateral force.
The minimum thickness is also determined by wall height soil classification and the height of unbalanced backfill or backfill on only one side of the wall.