Minimum depth of footing to be 24 inches below final grade and 12 inches below existing grade. Rebars are required in all dwelling and garage footers. A poorly embedded wall will lead a building to simply slide along the ground surface. This can be reduced to 450mm if ground conditions permit. Top of concrete cavity fill should be at least 150mm below any damp proof course and sloped to drain excess water to the outside of the building.
Please note that these guidance notes are for advice only and may not cover all situations. The other walls are 10 inches thick even though there is less soil pressing against them. Even concentrated loads from columns and beam pockets within a wall must be considered.
Traditional foundations – Masonry Foundation Dimensions
Brickwork and blockwork should be suitable for use below ground level. Footing size to be based on allowable soil pressure of 2000 pounds per square foot. Tie downs and footers need to meet manufactures specs. Damp-proofing of exterior basement required from footing to finished grade. But there are many other variables that control the thickness of the wall.
Vertical steel bars of a given thickness spaced a distinct distance apart and placed at a precise place within the wall can help ensure the wall will not fail.
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.
For example, a 10-inch thick wall may all of a sudden thicken to 16 inches for just a foot or so. It does the same job as a beam would do under a floor joist. Because the load spreads out, the pressure on the soil is greatest rightbeneath the footing. Also, soil from the embankment mayfall into the trench. Under load, it willreconsolidate and cause settling. The type and density of the nativesoil is also important.
I feel much better about cutting a 3’x 9-10′ section out of my basement wall now to add a single car garage door. Plus the builder will be on hand to ensure we have good structural support. My structural surveyor has been talking about 1 meter thickness of concrete, 750mm at minimum!
Garage floors shall be sloped toward the main vehicle entry doorway or to central drain. Ceiling fan outlet boxes must be listed and identified for fan support. Branch circuits wiring 14-2 or 12-2 copper, based on load. Heat producing appliances shall be installed with burners, burner ignition devices or heating elements and switches at least 18 inches above the garage floor level.
Accessible shutoff valves shall be within 6 feet of appliance and in same room or space for fuel and gas piping. Venting of fuel burning appliances. Minimum of 5 inch steel plate over plumbing that is not 1 1/4 inch back from the face of the stud wall. Shower valves to be of the pressure balancing type. Whirlpool tubs shall have access to motor-pump assembly. Masonry chimney construction requirements. Chimney clearances and hearth extension requirements. Factory built fireplace installation requirements. Chimneys shall extend at least 2 feet higher than any portion of the building within 10 feet, but shall not be less than 3 feet above the point where the chimney passes through the roof.
If the soil is very strong, this may not lead to problems. If there’s a keyway in the wall, fill it in, and if there’s steel projectingfrom the footing, cut it off. In weaker soils,
you have to augment the footing itself with steel and concrete. In weaker soils, you have to augment the footing itself with steel and concrete. An unreinforced footing that is too wide may crack close to thewall, overloading the soil beneath. In most residential situations, #4 rod at 12 inches o.c. If you’re going to add lengthwise steel, putit where it will do some good: in the wall, not the footing. When you form the footings, place enough large stone into the wet, muckyzone to get up above the water table. Concrete walls, on the other hand, can be reinforced with steel to spanopenings. The concrete has to be appropriately reinforced. For this detail, the footings are formed and cast as usual. Protection of horizontal insulation below ground. Clean crushed stone shall be free from organic, clayey or silty soils. Stem walls laterally supported at top. Stem walls not laterally supported at top.
Building A Concrete Block Foundation Bob Vila
Bob Vila and contractor John Clancy review construction of a concrete block foundation in Martha’s Vineyard, MA. For more on …