Foundation is the lower most part of a structure which forms a base for super structure. Before designing foundation, a designer should get all information regarding the nature and type of foundation. The basic purpose of this information gives help in fixing the bearing capacity of soil, selecting economical and safe type of foundation and fixing the depth of foundation.
The lowest part of structure which transmits all loads and is in direct contact with ground is called a foundation.
Term, foundation, includes the structure below the ground level. Artificial arrangement provided to transmit loads to the soil below are also included in this term e.g., piles, raft. Grillage concrete blocks etc.
To spread or distribute the weight of the structure over a large area.
To avoid unequal settlement of the soil below.
To provide a level surface the building.
To increase the stability of the structure and prevent it from over turning.
Classification of foundations:
Foundations can be broadly classified as under:-
Deep Foundation: The foundation of structure when taken deep to attain a bearing stratum suitable in all respects is called a Deep Foundation. Piles, cofferdams, caissons come under the deep foundation.
Shallow Foundation: A foundation placed immediately between the lowest part of the super structure is called Shallow Foundation. Shallow Foundation distributes the structural loads over a large area at shallow depth below the ground level.
Pile foundation is used where it is not possible simple spread foundation at a suitable depth because the stratum of required bearing capacity is at a greater depth or where there are steep slopes. A Pile foundation has a base of cement concrete or steel grillage foundation supported by piles. Piles are classified as:
Timber Piles, Concrete Piles, Composite or Steel Piles.
The following points be in fully be kept in mid while selecting a plot for residential building:-
The plot should be in fully developed locality or fast developing locality with availability of roads, water supply, electricity, drainage, etc. and preferably with other utilities like school, post and telegraph office, dispensary etc.
An are where by laws of local authorities enforce restrictions regarding open area, proportion of plot to be built, steel widths, house line, etc.
The plot should be rectangular, preferably, but should not be irregular in shape and with sharp corners.
The plot should be fairly high and leveled with uniform slope for quick drainage of rain water.
Soil should be light loamy on surface without any newly filled earth. Newly filled earth in a plot requires deep and expensive foundation. There should be firm soil, rock or sand below 600mm to 1200mm layer of light soil.
The plot should have unobstructed breeze and sun.
Plot near unhealthy, noisy or crowed localities and slums. Factories, water logged areas, badly maintained drains and nallahs should be avoided.
Legal and financial aspects are worthy of careful considerations. Title of plot should be clear.
Cost of plot should not exceed 35% of total amount to be invested in the house property.
It is advisable to consult a lawyer before purchasing a plot.
The planning of a building is based on following principles
Placing of rooms with respect to North is called Orientation. Room are kept in proper direction and also proper disposition of doors and windows in the exterior walls of different rooms so that the inmates of the house enjoy the gifts of nature such as fresh air, warmth, health giving morning sun rays and landscape. Fig. 17-1 shows the placing of different rooms with respect to North.
Privacy of whole house from highways and minor roads. It can be accomplished by providing walls, tall trees, hedges, creepers and screens etc.
Privacy inside the house can be accomplished by providing passages and lobbies, skilful placement of doors and opening, curtains and blinds in windows etc.
3. Grouping of rooms:
Placement of rooms in respect to their utility is called Grouping of Rooms. For example dining should be close to kitchen, sanitary services close to and easily accessible from each bed room and away from kitchen and dining etc.
Free movement of inmates of a house is called Circulation. Circulation is of two types:-
Horizontal Circulation: Circulation on same floor is called Horizontal Circulation. It can be accomplished by providing direct well lighted passage. Independent passage should to living, common room, lobby and staircase.
Vertical Circulation: Circulation between different floors is called Vertical Circulation. For vertical circulation between two different floors, staircase is only a thoroughfare. It should be well lighted, ventilated, easy to climb and broad. For public buildings ramp and lift are also provided.
For preservation of perfect health, sanitation is must. Building should be on an elevate site so that the rain water flows away easily. It should also be away from stagnant ponds, quarry (excavations) and other objectionable nuisance. Room should be well ventilated.
Provision of some space to be sued for some other overlapping activities. For example a drawing room or dining with flexibility portion in lounge can accommodate more guests on festive gatherings small parties. There are a number of such overlapping activities which require large space occasionally for which provision should made and provided.
An economical structure be planned and designed. And estimate of quantities should be prepared along with abstract of cost.
Design of a house depends on numerous conditions as a whether it is designed to meet the climatic conditions or with regard to availability of space.
Requirements of a house vary from person to person because styles and tastes have always differed. Everyone wants a different styles to the extent that it should look exceptionally different from the others. A house reflects the taste and styles of those who live in it.
Climatic conditions also play a major role in design. In hilly areas, roof is sloping and a fire chimney is provided as a safeguard snowfall and cold respectively. Design of a house is more elaborate and sophisticated in plains where climate is generally dry.
Style of architecture is most important while planning a house.
Following are the styles of architecture:
Geometric Style: A geometric house is composed of arches and cylinders. All the doors and windows are covered with round projections along with small hut type slabs. Arches also give a good height to the structure. While designing such house, designer should be careful about composition of arches, circles, cylinders and hut type slopes.
Box Style: Box style architecture is economical and easily planned. It is a combination of balconies, chajjas and canopies. Such house, if properly designed, givens a compact and neat look.
Villa Styles: such architecture is like old villa.
There are generally four types of internal planning of a house.
Single Unit: Single unit is only for one family. It consists of ground floor, mezzanine and first floor with barsati. It can also have a basement.
Duplex: Two vertical units are made, instead of a single, on a corner, rectangular length and such arrangement is called Duplex. In duplex one can enjoy the comforts of a single unit and at the same time other unit can be rented out.
Typical Vertical Unit: In vertical unit, ground floor and mezzanine are converted into single unit and separate independent stair case is provided for first floor. First floor can be rented out independently.
Flats: In flats whole unit is built on ground floor and further unit is added on first floor. In this way maximum number of units can be added on each floor for rental purpose. This system is actually a business or rental style.
Basic Elements of Planning a Residential Building
A residential building has the following living requirements:
The plan drawn with single line showing different positions of rooms with dimensions excluding the thickness of walls is called Line Plan.
After determining the plinth area and shape of building, draw the North line is a corner to facilitate the orientation of different rooms. The line plan should be started either with a kitchen or with bed rooms. After kitchen, dining should be provided adjacent to it. Bath and W.C. should have at least one side exposed to sunlight and air. They should be approachable and provided with each bed room independently (preferably). Now provide drawing room or living room and lounge, staircase should be provided in the lounge or separately when upper floor is to rented out. Provide store with master bed room. After this position of doors and windows be determined. They should be arranged that they do not come in the way of beds of furniture etc.
The floor plan and dimensions (above) were created in MODEL SPACE at a 1:1 scale. The walls were drawn to be 30' or more long.
The title block and viewport were created in a LAYOUT TAB / PAPER SPACE at a 1:1 scale. The title block is 8-1/2 x 11 inches.
The viewport is a window into "model space". In the image below, the viewport is the black rectangle and the contents of the viewport are displayed inside it. The contents of the viewport are scaled to either fit the viewport or (preferably) to conform to a specific drafting scale (ie: 1"=1')
View Port This conceptual image shows the relationship between model space and a Layout.