A foundation (or, more commonly, base) is the element of an architectural structure which connects it to the ground and transfers loads from the structure to the ground. Foundations are generally considered either shallow or deep. Foundation engineering is the application of soil mechanics and rock mechanics (Geotechnical engineering) in the design of foundation elements of structures.
Table of Contents
Historic foundation types
The simplest foundation, a pad-stone. Latvian Ethnographic Open Air Museum
Earth fast or post in ground construction
Buildings and structures have a long history of being built with wood in contact with the ground. Post in ground construction may technically have no foundation. Timber pilings were used on soft or wet ground even below stone or masonry walls. In marine construction and bridge building a crisscross of timbers or steel beams in concrete is called grillage.
Perhaps the simplest foundation is the padstone, a single stone which both spreads the weight on the ground and raises the timber off the ground. Staddle stones are a specific type of padstones.
Dry stone and stones laid in mortar to build foundations are common in many parts of the world. Dry laid stone foundations may have been painted with mortar after construction. Sometimes the top, visible course of stone is hewn, quarried stones. Besides using mortar, stones can also be put in a gabion. One disadvantage is that if using regular steel rebars, the gabion would last much less long than when using mortar (due to rusting). Using weathering steel rebars could reduce this disadvantage somewhat.
Rubble trench foundations
Main article: Rubble trench foundation
Rubble trench foundations are a shallow trench filled with rubble or stones. These foundations extend below the frost line and may have a drain pipe which helps groundwater drain away. They are suitable for soils with a capacity of more than 10 tonnes/m² (2,000 pounds per square foot).
Gallery of shallow foundation types
Drawing of Poteaux-en-Terre post in ground type of wall construction (this example technically called pallisade construction) in the Beauvais House in Ste Genevieve, Missouri, U.S.A.
PSM V24 D321 A primitive stilt house in Switzerland on wood pilings.
A granary on staddle stones, a type of padstone
Black Eagle Dam – cross-section of construction plans for 1892 structure
Davis House dry-laid stone foundation ruin, Gardiner, NY
A basic type of rubble trench foundation
Typical residential poured concrete foundation, except for the lack of anchor bolts. The concrete walls are supported on continuous footings. There is also a concrete slab floor. Note the standing water in the perimeter French drain trenches.
Modern foundation types
Main article: Shallow foundation
Shallow foundation construction example
Shallow foundations, often called footings, are usually embedded about a metre or so into soil. One common type is the spread footing which consists of strips or pads of concrete (or other materials) which extend below the frost line and transfer the weight from walls and columns to the soil or bedrock.
Another common type of shallow foundation is the slab-on-grade foundation where the weight of the structure is transferred to the soil through a concrete slab placed at the surface. Slab-on-grade foundations can be reinforced mat slabs, which range from 25 cm to several meters thick, depending on the size of the building, or post-tensioned slabs, which are typically at least 20 cm for houses, and thicker for heavier structures.
Main article: Deep foundation
A deep foundation is used to transfer the load of a structure down through the upper weak layer of topsoil to the stronger layer of subsoil below. There are different types of deep footings including impact driven piles, drilled shafts, caissons, helical piles, geo-piers and earth stabilized columns. The naming conventions for different types of footings vary between different engineers. Historically, piles were wood, later steel, reinforced concrete, and pre-tensioned concrete.
Main article: Monopile foundation
A monopile foundation is a type of deep foundation which uses a single, generally large-diameter, structural element embedded into the earth to support all the loads (weight, wind, etc.) of a large above-surface structure.
A large number of monopile foundations have been utilized in recent years for economically constructing fixed-bottom offshore wind farms in shallow-water subsea locations. For example, a single wind farm off the coast of England went online in 2008 with over 100 turbines, each mounted on a 4.74-meter-diameter monopile footing in ocean depths up to 16 metres of water.
Inadequate foundations in muddy soils below sea level caused these houses in the Netherlands to subside.
Foundations are designed to have an adequate load capacity depending on the type of subsoil supporting the foundation by a geotechnical engineer, and the footing itself may be designed structurally by a structural engineer. The primary design concerns are settlement and bearing capacity. When considering settlement, total settlement and differential settlement is normally considered. Differential settlement is when one part of a foundation settles more than another part. This can cause problems to the structure which the foundation is supporting. Expansive clay soils can also cause problems.
WALLS: Building wall
The purposes of the walls in buildings are to support roofs, floors and ceilings; to enclose a space as part of the building envelope along with a roof to give buildings form; and to provide shelter and security. In addition, the wall may house various types of utilities such as electrical wiring or plumbing. Wall construction falls into two basic categories: framed walls or mass-walls. In framed walls the load is transferred to the foundation through posts, columns or studs. Framed walls most often have three or more separate components: the structural elements (such as 2×4 studs in a house wall), insulation, and finish elements or surfaces (such as drywall or panelling). Mass-walls are of a solid material including masonry, concrete including slipform stonemasonry, log building, cordwood construction, adobe, rammed earth, cob, earthbag construction, bottles, tin cans, straw-bale construction, and ice.
There are three basic methods walls control water intrusion: moisture storage, drained cladding, or face-sealed cladding. Moisture storage is typical of stone and brick mass-wall buildings where moisture is absorbed and released by the walls of the structure itself. Drained cladding also known as screened walls acknowledges moisture will penetrate the cladding so a moisture barrier such as housewrap or felt paper inside the cladding provides a second line of defense and sometimes a drainage plane or air gap allows a path for the moisture to drain down through and exit the wall. Sometimes ventilation is provided in addition to the drainage plane such as in rainscreen construction. Face-sealed also called barrier wall or perfect barrier cladding relies on maintaining a leak-free surface of the cladding. Examples of face sealed cladding are the early exterior insulation finishing systems, structural glazing, metal clad panels, and corrugated metal.
Building walls frequently become works of art, externally and internally, such as when featuring mosaic work or when murals are painted on them; or as design foci when they exhibit textures or painted finishes for effect.
Main article: Curtain wall (architecture)
In architecture and civil engineering, curtain wall refers to a building facade that is not load-bearing but provides decoration, finish, front, face, or historical preservation.
Precast Compound Wall
Precast Compound Wall are Ready to use. it can be fast to install compare to brick and other walls, low cost compare to brick walls,
Main article: Mullion wall
Mullion walls are a structural system that carries the load of the floor slab on prefabricated panels around the perimeter.
Murno Gladst Wall
Main article: Murno Gladst Fence
A tall, deep-base exterior security wall which deters intrusion by climbing and tunneling. Also known as a Murno Gladst Fence
Glass Partition Wall
A partition wall is a wall that separates rooms, or divides a room. Partition walls are usually not load-bearing. Partition walls are constructed of many materials, including steel panels, bricks, blocks of clay, terra-cotta, concrete, or glass blocks.
Some partition walls are made of sheet glass. Glass partition walls are a series of individual toughened glass panels mounted in wood or metal framing. They may be suspended from or slide along a robust aluminium ceiling track. The system does not require the use of a floor guide, which allows easy operation and an uninterrupted threshold.
A timber partition consists of a wooden framework, supported on the floor or by side walls. Metal lath and plaster, properly laid, forms a reinforced partition wall. Partition walls constructed from fibre cement backer board are popular as bases for tiling in kitchens or in wet areas like bathrooms. Galvanized sheet fixed to wooden or steel members are mostly adopted in works of temporary character. Plain or reinforced partition walls may also be constructed from concrete, including pre-cast concrete blocks. Metal framed partitioning is also available. This partition consists of track (used primarily at the base and head of the partition) and studs (vertical sections fixed into the track typically spaced at 24″, 16″, or at 12″).
Internal wall partitions, also known as office partitioning, is usually made of plasterboard (drywall) or varieties of glass. Toughened glass is a common option, as is low-iron glass (better known as opti-white glass, which increases light and solar heat transmission.
Wall partitions are constructed using beads and tracking that is either hung from the ceiling or fixed into the ground. The panels are inserted into the tracking and fixed. Some wall partition variations specify their fire resistance and acoustic performance rating.
Main article: Party wall
Party walls are walls that separate buildings or units within a building. They provide fire resistance and sound resistance between occupants in a building. The minimum fire resistance and sound resistance required for the party wall is determined by a building code and may be modified to suit a variety of situations. Ownership of such walls can become a legal issue. It is not a load-bearing wall and may be owned by different people.
Main article: Infill wall
An infill wall is the supported wall that closes the perimeter of a building constructed with a three-dimensional framework structure.
Main article: Firewall (construction)
Fire walls resist spread of fire within or sometimes between structures to provide passive fire protection. A delay in the spread of fire gives occupants more time to escape and fire fighters more time to extinguish the fire. Such walls have no windows, and are made of non-combustible material such as concrete, cement block, brick, or fire rated drywall—and have wall penetrations sealed with special materials. A doorway in a firewall must have a rated fire door. Fire walls provide varying resistance to the spread of fire, some intended to last one to four hours. Firewalls, generally, can also act as smoke barriers when constructed vertically from slab to roof deck and horizontally from an exterior wall to exterior wall subdividing a building into sections. When constructed in this manner the fire wall can also be referred to as an Area Separation Wall.
Main article: Shear wall
Shear walls resist lateral forces such as in an earthquake or severe wind. There are different kinds of shear walls such as the steel plate shear wall.
Main article: Knee wall
Knee walls are short walls that either support rafters or add height in the top floor rooms of houses. In a 1 1⁄2-story house, the knee wall supports the half story.
Main article: Cavity wall
Cavity walls are walls made with a space between two “skins” to inhibit heat transfer.
Pony wall (or dwarf wall) is a general term for short walls, such as:
- A half wall that only extends partway from floor to ceiling, without supporting anything
- A stem wall—a concrete wall that extends from the foundation slab to the cripple wall or floor joists
- A cripple wall—a framed wall from the stem wall or foundation slab to the floor joists
- Define foundation
- Mention 4 types of foundation