House Construction/Setting the Stage

Setting the Stage

Building Orientation

Orientation is defined as the position of building in relation to seasonal variation in the sun's path as well as prevailing wind pattern

Grading, Terra-planing and Site Preparation

A house under construction in Milyanfan village, apparently with both adobe bricks and regular bricks being used.

The site you are building on should be flat, with no lumps or hillocks. To level, you could hire a bulldozer and go over the land with the blade close to the ground to remove all lumps or hillocks. If the plot is on a severe incline, then lay stilts out so that you can lay out a floor level on top of them.

At times, ground filling has to be done to raise ground to the required level.

Foundation Construction

Oxnard, Calif. (Jan. 10, 2004) -- Members of Naval Mobile Construction Battalion Four (NMCB-4) work to level concrete in the foundation of a Habitat for Humanity house located in Oxnard, Calif. NMCB-4 is home ported in Port Hueneme, Calif. U.S. Navy photo by Photographer’s Mate 2nd Class Philip Forrest.

An integral part of home building as the structure will depend on it for load-bearing and to survive the environment. Considerations will not stop on immediate necessities like soil structure and characteristics but must be planed to deal with the probability of drastic environmental hazards, from floods, earthquakes even tornadoes.

In most construction, concrete is used as foundation. It is laid into a trench up to 3 or 4 feet deep, and provides a very solid foundation for whatever building material used. There are many different types of foundations.

The most typical foundation is made up of a footing which is the portion of the steel reinforced concrete that bears on the undisturbed soil. Footings are typically 12" 16" up to 36" inches wide by 10" to 12" deep depending on the soil on which they are bearing.

A foundation wall is general applied over the footing to above grade. Foundation walls are typically 8" wide and terminate 8' above the finished grade. like column footing , pile, raft etc. these are used as per condition of soil. Waterproofing, dam-proofing and drainage are typically applied at the exterior of the foundation and footing. This is particularly important when building in wet soils.

The foundation is the most critical part of any structure. The structural failures due to faulty workmanship or to an insufficient thickness of the walls are rare in comparison with those due to defective foundations. When it is necessary, as so frequently it is at the present day, to erect gigantic edifices—as high buildings or long-span bridges—on weak and treacherous soils, the highest constructive skill is required to supplement the weakness of the natural foundation by such artificial preparations as will enable it to sustain the load with safety.

Natural Foundations. The soils comprised under this head may be divided into two classes. (1) Those whose stability is not affected by water, and which are firm enough to support the structure, such as rock, compact gravels, and hard clay, and (2) soils which are firm enough to support the weight of the structure, but whose stability is affected by water, such as loose gravels., sand, clay and loam.

Foundations on Rock. To prepare a rock foundation, all that is generally necessary is to cut away the loose and decayed portions and to dress the surface so exposed to a plane as nearly perpendicular to the direction of the pressure as practicable; or, if the rock forms an inclined plane, to cut a series of plane surfaces, like those of steps, for the walls to rest upon. If there are any fissures in the rock they should be filled with concrete.

Foundations on Gravel, Etc. In dealing with soils of this kind usually nothing more is required than to cover them with a layer of concrete of width and depth sufficient to distribute the weight properly.

Foundations on Sand. Sand is almost incompressible so long as it is not allowed to spread out laterally, but as it has no cohesion, and acts like a fluid when exposed to running water, it must be treated with great caution.

Foundations on Clay. Clay is much affected by the action of water, and hence the ground should be well drained before the work is begun, and the trenches so arranged that water does not remain in them. In general, the less a soil of this kind is exposed to the action of the air, and the sooner it is protected from exposure, the letter for the work. The top of the footings must be carried below the frost line to prevent heaving, and for the same reason the outside face of the wall should be built with a slight batter and perfectly smooth. The frost line attains a depth of six feet in some of the northern states.

The tearing power of clay and loamy soils may be greatly increased: (1) By increasing the depth. (2) By drainage. This may be accomplished by a covering of gravel or sand, the thickness depending upon the plasticity of the soil, and by surrounding the foundation walls with a tile drain. If springs are encountered the water may be excluded by sheet pilings, puddling or plugging the spring with concrete. (3) By consolidating the soil. This may te done by driving short piles Hose together, or by driving piles, then withdrawing them air filling the space immediately with damp sand well rammed. If the soil is very loose and wet, sand will not be effective, and concrete will be found more satisfactory.

Artificial Foundations. When the ground in its natural state is too soft to bear the weight of the proposed structure, recourse must be had to artificial means of support, and, in doing this, whatever mode of construction is adopted, the principle must always be that of extending the bearing surface as much as possible.

Foundations on Mud, silt, marshy or compressible soils are generally formed in one of three ways: (1) By driving piles in which the footings are supported. (2) By spreading the footings either by-layers of timber, steel beams, or concrete, or a combination of either. (3) By sinking caissons of iron or steel, excavating the soil from the interior, and filling with concrete.