Residential Subdivisions Are Mass Graded

Subdivisions are mass graded. This means an undesirable building location(lots of steep grade are uneven lots) is transformed into individual flat or moderately sloped lots by movement of dirt. This usally includes removal of soil at hill(the cut lot),which which is them imported to other areas on site to create fill areas(the fill lot) or cut-fill areas(transitional lot).Cut lot tens to perform well since the soil is undisturbed where the hill was removed.Fill lot can compact more once the home is completed;this movement,however,is usually uniform and rarely cause distress th the home. These condition are consider when inspecting a home when built from mass graded lots. The homes soil,and foundation are in constant movement and forces fighting against one another.New homes may not give any indication of foundation issues for several years down the road.Although there are methods for inspectors to gauge that accurate standards were followed site prep,and adequate footing drains to help with hydrostatic pressure against the structures foundation.A strong foundation and proper lot drainage is the key to a stable foundation.In a perfect world every property would be built on the perfect lot,but as I know and you should as well this can not always be the chase.

A structure is expected to stand up. The force of gravity is constantly working to bring it down.A structure has to be designed to resist gravity.It must support its own weight,which is called DEADLOAD of the structure.It must also support the live load which are imposed open it,which include the people inside,the furniture,and other weight such as snow,and the materials used in the roof structure skeleton.
A structure does transfer its weight through the exterior walls,and load bearing partions to the foundation which in then transfers the weight to the soil through the footing.Not only is a structure expected to stand up, it is also expected to stand still. The structure movement is partially determined by the conditions of the soil support the structure,and proper drainage around the stucture.When the ground below the house fails,the house sinks, soil moves. The foundation resists the pressure of the soil against the structure.Homes built on the proper site should be built strong enough to resist this natural pressure.

MOVEMENT:
The effects of settlement and movement on a home and their effects on the rest of the structure are not always obvious.While some signs are obvisous,other signs might need more in depth study to determine the cause of underlying issues.Wall cracks appear as the result of overloading or because of settlement or heaving. The location of the cracks can be a clue to what is going on to the foundation.

Is a dynamic system.Soil Moves.A house built on the bottom of a hill can have soil moving toward it over time and exerting more and more pressure against the foundation.It may be pushed from its original position.

WINDS
Plays an effective upon a structure.With heavy winds theres forces of pulling,and uplifting.Structures must be strong enough to resist these forces as well.

Vertical Cracks:
Are most often caused as a result of settlement of the structure,soilcompacting,or soil washing away under the footings.It occurs when there is an upward overload force next to a downwards overload force. They can also occur after remolding,when new dead loads are added to the structure,or by adding very heavy live loads.
Vertical cracks that extend down to the footings may be serious and should be investigated carefully. This could be cause by uneven settlement of the building and could indicate the wall is separating-one part settling more on one side of the crack than the other. The crack extending to the footing could also indicate a failure of material such deteriorating block,decayed mortar,or weak concrete,or improper construction standards.

Angled Cracks:
Appear when the upload and download force offset each other. They can appear when there is major difference in the soil under the home from one location to another,heaving of the soil,and resulting footing failure.Angled cracks can appear in pairs,where a load in one direction is offset by a pair of loads from other direction.When a crack is a single corner of the house,it can indicate a broken footing because of the soil underneath,expansive clay soilsor even the uplift from heavy tree roots in that location.

Horizontal Cracks:
On the foundation stem wall can indicate pressure being applied from the outside. The cause can be soil pressure against the wall,improper backfilling,and surface problems such as poor downspouts,Grade of lot,surface water drainage that allow water to pool around the foundation and increases the pressure pushing against the wall.When the wall is actually displaced-when the surface of the wall is out of alignment and the crack is wider on the inside face of the wall,serious problems can result.
There are other cause for horizontal cracks in foundation walls. There could be a vertical overload on the wall.Or the crack could be caused by settlement,where the wall has dropped when the soil underneath settled.

Internal Stresses:
The integrity of a structure depends on each individual structure members.A structure is in a constant state of Stress as individual member extert forces upon each other.For example,Floor joists spanning the structure would sag without the restraints and support provided by girders,which in turn push on supporting columns. These supoort systems must work in concert with each other without excerting more load to one another and resulting in damage.Structural member have two forces working on them at all times compression,and tension.Members of the structure has forces such as shearing,and bending.Individual members may fail under these stresses.A home inspection, the inspector looks for these underlying problems.

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