Framing (construction)
Encyclopedia
Framing, in construction known as light-frame construction, is a building technique based around structural members, usually called studs
Wall stud
A wall stud is a vertical member in the light frame construction techniques called balloon framing and platform framing of a building's wall.-Purpose:...

, which provide a stable frame to which interior and exterior wall
Wall
A wall is a usually solid structure that defines and sometimes protects an area. Most commonly, a wall delineates a building and supports its superstructure, separates space in buildings into rooms, or protects or delineates a space in the open air...

 coverings are attached, and covered by a roof
Roof
A roof is the covering on the uppermost part of a building. A roof protects the building and its contents from the effects of weather. Structures that require roofs range from a letter box to a cathedral or stadium, dwellings being the most numerous....

 comprising horizontal ceiling joist
Joist
A joist, in architecture and engineering, is one of the horizontal supporting members that run from wall to wall, wall to beam, or beam to beam to support a ceiling, roof, or floor. It may be made of wood, steel, or concrete. Typically, a beam is bigger than, and is thus distinguished from, a joist...

s and sloping rafter
Rafter
A rafter is one of a series of sloped structural members , that extend from the ridge or hip to the downslope perimeter or eave, designed to support the roof deck and its associated loads.-Design:...

s (together forming a truss
Truss
In architecture and structural engineering, a truss is a structure comprising one or more triangular units constructed with straight members whose ends are connected at joints referred to as nodes. External forces and reactions to those forces are considered to act only at the nodes and result in...

 structure) or manufactured pre-fabricated roof truss
Truss
In architecture and structural engineering, a truss is a structure comprising one or more triangular units constructed with straight members whose ends are connected at joints referred to as nodes. External forces and reactions to those forces are considered to act only at the nodes and result in...

es—all of which are covered by various sheathing materials to give weather resistance.

Modern light-frame structures usually gain strength from rigid panels (plywood
Plywood
Plywood is a type of manufactured timber made from thin sheets of wood veneer. It is one of the most widely used wood products. It is flexible, inexpensive, workable, re-usable, and can usually be locally manufactured...

 and other plywood-like composites such as oriented strand board
Oriented strand board
Oriented strand board, also known as OSB and SmartPly , is an engineered wood product formed by layering strands of wood in specific orientations. In appearance, it may have a rough and variegated surface with the individual strips Oriented strand board, also known as OSB (UK) and SmartPly (UK &...

 (OSB) used to form all or part of wall sections) but until recently carpenter
Carpenter
A carpenter is a skilled craftsperson who works with timber to construct, install and maintain buildings, furniture, and other objects. The work, known as carpentry, may involve manual labor and work outdoors....

s employed various forms of diagonal bracing (called wind braces) to stabilize walls. Diagonal bracing remains a vital interior part of many roof systems, and in-wall wind braces are required by building codes in many municipalities or by individual state law
U.S. state
A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...

s in the United States.

Light frame construction using standardized dimensional lumber has become the dominant construction method in North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

 and Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

 because of its economy
Economy
An economy consists of the economic system of a country or other area; the labor, capital and land resources; and the manufacturing, trade, distribution, and consumption of goods and services of that area...

. Use of minimal structural materials allows builders to enclose a large area with minimal cost, while achieving a wide variety of architectural styles. The ubiquitous platform framing and the older balloon framing are the two different light frame construction systems used in North America.

Walls

Wall framing in house construction includes the vertical and horizontal members of exterior walls and interior partitions, both of bearing walls and non-bearing walls. These stick members, referred to as stud
Wall stud
A wall stud is a vertical member in the light frame construction techniques called balloon framing and platform framing of a building's wall.-Purpose:...

s, wall plate
Wall plate
A wall plate, a structural element in the light frame construction method known as platform framing, is a horizontally laid structural element at right angles to the load-bearing part of the vertical load of a building...

s and lintels (headers), serve as a nailing base for all covering material and support the upper floor platforms, which provide the lateral strength along a wall. The platforms may be the boxed structure of a ceiling
Ceiling
A ceiling is an overhead interior surface that covers the upper limit of a room. It is generally not a structural element, but a finished surface concealing the underside of the floor or roof structure above....

 and roof, or the ceiling and floor
Floor
A floor is the walking surface of a room or vehicle. Floors vary from simple dirt in a cave to many-layered surfaces using modern technology...

 joist
Joist
A joist, in architecture and engineering, is one of the horizontal supporting members that run from wall to wall, wall to beam, or beam to beam to support a ceiling, roof, or floor. It may be made of wood, steel, or concrete. Typically, a beam is bigger than, and is thus distinguished from, a joist...

s of the story above. The technique is variously referred to colloquially in the building trades as stick and frame, stick and platform, or stick and box as the sticks (studs) give the structure its vertical support, and the box shaped floor sections with joists contained within length-long post and lintel
Post and lintel
Post and lintel, or in contemporary usage Post and beam, is a simple construction method using a lintel, header, or architrave as the horizontal member over a building void supported at its ends by two vertical columns, pillars, or posts...

s (more commonly called headers), supports the weight of whatever is above, including the next wall up and the roof above the top story. The platform also provides the lateral support against wind and holds the stick walls true and square. Any lower platform supports the weight of the platforms and walls above the level of its component headers and joists.

Framing lumber
Lumber
Lumber or timber is wood in any of its stages from felling through readiness for use as structural material for construction, or wood pulp for paper production....

 should be grade-stamped, and have a moisture content not exceeding 19%.

There are three historically common methods of framing a house.
  • Post and Beam, which is now used predominately in barn construction.
  • Balloon framing using a technique suspending floors from the walls was common until the late 1940s, but since that time, platform framing has become the predominant form of house construction.
  • Platform framing often forms wall sections horizontally on the sub-floor prior to erection, easing positioning of studs and increasing accuracy while cutting the necessary manpower. The top and bottom plates are end-nailed to each stud with two nails at least 3.25 in (82.6 mm) in length (16d or 16 penny nails). Studs are at least doubled (creating posts) at openings, the jack stud being cut to receive the lintels(headers) that are placed and end-nailed through the outer studs.


Wall sheathing, usually a plywood or other laminate, is usually applied to the framing prior to erection, thus eliminating the need to scaffold
Scaffolding
Scaffolding is a temporary structure used to support people and material in the construction or repair of buildings and other large structures. It is usually a modular system of metal pipes or tubes, although it can be from other materials...

, and again increasing speed and cutting manpower needs and expenses. Some types of exterior sheathing, such as asphalt-impregnated fibreboard
Fiberboard
Fiberboard is known as low density fiberboard is a type of engineered wood product that is made out of wood fibers. Types of fiberboard include particle board, medium-density fiberboard, and hardboard. Fiberboard is sometimes used as a synonym for particle board, but particle board usually refers...

, plywood
Plywood
Plywood is a type of manufactured timber made from thin sheets of wood veneer. It is one of the most widely used wood products. It is flexible, inexpensive, workable, re-usable, and can usually be locally manufactured...

, oriented strand board
Oriented strand board
Oriented strand board, also known as OSB and SmartPly , is an engineered wood product formed by layering strands of wood in specific orientations. In appearance, it may have a rough and variegated surface with the individual strips Oriented strand board, also known as OSB (UK) and SmartPly (UK &...

 and waferboard
Waferboard
Waferboard belongs to the subset of reconstituted wood panel products called flakeboards, which is a type of particleboard. It is a structural material made from rectangular wood flakes of controlled length and thickness bonded together with waterproof phenolic resin under extreme heat and...

, will provide adequate bracing to resist lateral loads and keep the wall square. (Construction codes in most jurisdictions require a stiff plywood sheathing.) Others, such as rigid glass-fibre, asphalt-coated fibreboard, polystyrene
Polystyrene
Polystyrene ) also known as Thermocole, abbreviated following ISO Standard PS, is an aromatic polymer made from the monomer styrene, a liquid hydrocarbon that is manufactured from petroleum by the chemical industry...

 or polyurethane
Polyurethane
A polyurethane is any polymer composed of a chain of organic units joined by carbamate links. Polyurethane polymers are formed through step-growth polymerization, by reacting a monomer with another monomer in the presence of a catalyst.Polyurethanes are...

 board, will not. In this latter case, the wall should be reinforced with a diagonal wood or metal bracing inset into the studs. In jurisdictions subject to strong wind storms (hurricane countries, tornado alleys) local codes or state law will generally require both the diagonal wind braces and the stiff exterior sheathing regardless of the type and kind of outer weather resistant coverings.

Corners

A multiple-stud post made up of at least three studs, or the equivalent, is generally used at exterior corners and intersections to secure a good tie between adjoining walls and to provide nailing support for the interior finish and exterior sheathing. Corner
Corner
A corner is the place where two lines meet at an angle, and a concave corner of intersecting walls is generally thought to be the least beneficial position to be in a life-or-death situation. From this notion was born the verb to corner, which is used to mean "to back into a corner" and usually...

s and intersections, however, must be framed with at least two studs.

Nailing support for the edges of the ceiling is required at the junction of the wall and ceiling where partitions run parallel to the ceiling joists. This material is commonly referred to as 'dead wood' or backing.

Exterior wall studs

Wall framing in house construction
Construction
In the fields of architecture and civil engineering, construction is a process that consists of the building or assembling of infrastructure. Far from being a single activity, large scale construction is a feat of human multitasking...

 includes the vertical and horizontal members of exterior walls and interior partitions. These members, referred to as stud
Wall stud
A wall stud is a vertical member in the light frame construction techniques called balloon framing and platform framing of a building's wall.-Purpose:...

s, wall plates and lintels, serve as a nailing base for all covering material and support the upper floors, ceiling and roof.

Exterior wall studs are the vertical members to which the wall sheathing and cladding
Cladding (construction)
Cladding is the application of one material over another to provide a skin or layer intended to control the infiltration of weather elements, or for aesthetic purposes....

 are attached. They are supported on a bottom plate or foundation sill and in turn support the top plate. Studs usually consist of 2 × or 2 × lumber and are commonly spaced at 16 in (406.4 mm) on centre. This spacing may be changed to 12 in (304.8 mm) or 24 in (609.6 mm) on centre depending on the load
Structural load
Structural loads or actions are forces, deformations or accelerations applied to a structure or its components.Loads cause stresses, deformations and displacements in structures. Assessment of their effects is carried out by the methods of structural analysis...

 and the limitations imposed by the type and thickness of the wall covering used. Wider 2 × studs may be used to provide space for more insulation
Building insulation
building insulation refers broadly to any object in a building used as insulation for any purpose. While the majority of insulation in buildings is for thermal purposes, the term also applies to acoustic insulation, fire insulation, and impact insulation...

. Insulation beyond that which can be accommodated within a 3.5 in (88.9 mm) stud space can also be provided by other means, such as rigid or semi-rigid insulation or batts between 2 × horizontal furring strips
Furring
In light-frame construction, furring strips are long thin strips of wood or metal used to make backing surfaces to support the finished surfaces in a room. Furring refers to the backing surface, the process of installing it, and may also refer to the strips themselves. "Firring" is a U.K...

, or rigid or semi-rigid insulation sheathing to the outside of the studs. The studs are attached to horizontal top and bottom wall plates of 2 in (nominal) (38 mm) lumber that are the same width as the studs.

Interior partitions

Interior partitions supporting floor
Floor
A floor is the walking surface of a room or vehicle. Floors vary from simple dirt in a cave to many-layered surfaces using modern technology...

, ceiling or roof loads are called loadbearing walls; others are called non-loadbearing or simply partitions. Interior loadbearing walls are framed in the same way as exterior walls. Studs are usually 2 × lumber spaced at 16 in (406.4 mm) on centre. This spacing may be changed to 12 in (304.8 mm) or 24 in (609.6 mm) depending on the loads supported and the type and thickness of the wall finish used.

Partitions can be built with 2 × or 2 × studs spaced at 16 or 24 in (400 or 600 mm) on center depending on the type and thickness of the wall finish used. Where a partition does not contain a swinging door, 2 × studs at 16 in (406.4 mm) on centre are sometimes used with the wide face of the stud parallel
Parallel (geometry)
Parallelism is a term in geometry and in everyday life that refers to a property in Euclidean space of two or more lines or planes, or a combination of these. The assumed existence and properties of parallel lines are the basis of Euclid's parallel postulate. Two lines in a plane that do not...

 to the wall. This is usually done only for partitions enclosing clothes closets or cupboards to save space. Since there is no vertical load to be supported by partitions, single studs may be used at door openings. The top of the opening may be bridged with a single piece of 2 in (nominal) (38 mm) lumber the same width as the studs. These members provide a nailing support for wall finish, door frames and trim
Molding (decorative)
Molding or moulding is a strip of material with various profiles used to cover transitions between surfaces or for decoration. It is traditionally made from solid milled wood or plaster but may be made from plastic or reformed wood...

.

Lintels (headers)

Lintels (or, headers) are the horizontal members placed over window, door and other openings to carry loads to the adjoining studs. Lintels are usually constructed of two pieces of 2 in (nominal) (38 mm) lumber separated with spacers to the width of the studs and nailed together to form a single unit. The preferable spacer material is rigid insulation. The depth of a lintel is determined by the width of the opening and vertical loads supported.

Wall Sections

The complete wall sections are then raised and put in place, temporary braces added and the bottom plates nailed through the subfloor to the floor framing members. The braces should have their larger dimension on the vertical and should permit adjustment of the vertical position of the wall.

Once the assembled sections are plumbed, they are nailed together at the corners and intersections. A strip of polyethylene
Polyethylene
Polyethylene or polythene is the most widely used plastic, with an annual production of approximately 80 million metric tons...

 is often placed between the interior walls and the exterior wall, and above the first top plate of interior walls before the second top plate is applied to attain continuity of the air barrier
Air barrier
Air barriers control air leakage into and out of the building envelope. Air barrier products may take several forms:*Mechanically-attached membranes, also known as housewraps, usually a polyethylene-fiber or spun-bonded polyolefin , such as Tyvek is a generally accepted moisture barrier and an air...

 when polyethylene is serving this function.

A second top plate, with joints offset at least one stud space away from the joints in the plate beneath, is then added. This second top plate usually laps the first plate at the corners and partition intersections and, when nailed in place, provides an additional tie to the framed walls. Where the second top plate does not lap the plate immediately underneath at corner and partition intersections, these may be tied with 0.036 in (0.9144 mm) galvanized steel plates at least 3 in (76.2 mm) wide and 6 in (152.4 mm) long, nailed with at least three 2.5 in (63.5 mm) nails to each wall.

Balloon framing

Balloon framing is a method of wood
Wood
Wood is a hard, fibrous tissue found in many trees. It has been used for hundreds of thousands of years for both fuel and as a construction material. It is an organic material, a natural composite of cellulose fibers embedded in a matrix of lignin which resists compression...

 construction—also known as "Chicago construction" in the 19th century—used primarily in Scandinavia
Scandinavia
Scandinavia is a cultural, historical and ethno-linguistic region in northern Europe that includes the three kingdoms of Denmark, Norway and Sweden, characterized by their common ethno-cultural heritage and language. Modern Norway and Sweden proper are situated on the Scandinavian Peninsula,...

, Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

 and the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...

 (up until the mid-1950s). It utilizes long continuous framing members (studs) that run from the sill plate
Sill plate
A sill plate or sole plate in construction and architecture is the bottom horizontal member of a wall or building to which vertical members are attached. Sill plates are usually composed of lumber. It usually comes in sizes of 2×4, 2×6, 2×8, and 2×10. In the platform framing method the sill plate...

 to the top plate, with intermediate floor structures let into and nailed to them. Here the heights of window sills, headers and next floor height would be marked out on the studs with a storey pole
Storey pole
Rarely used in building construction after the mass production of the steel tape measure, a storey pole is a length of narrow board, often a 1x4 usually cut to the height of one storey...

. Once popular when long lumber was plentiful, balloon framing has been largely replaced by platform framing.

While no one can be sure who introduced balloon framing in the U.S., the first building using balloon framing was probably a warehouse constructed in 1832 in Chicago
Chicago
Chicago is the largest city in the US state of Illinois. With nearly 2.7 million residents, it is the most populous city in the Midwestern United States and the third most populous in the US, after New York City and Los Angeles...

 by George Washington Snow. The following year, Augustine Taylor (1796–1891) constructed St. Mary's Catholic Church in Chicago
Chicago
Chicago is the largest city in the US state of Illinois. With nearly 2.7 million residents, it is the most populous city in the Midwestern United States and the third most populous in the US, after New York City and Los Angeles...

 using the balloon framing method. Alternatively, the balloon frame has been shown to have been introduced in Missouri as much as fifty years earlier.

The name comes from a French Missouri type of construction, maison en boulin. The curious name of this framing technique is conventionally thought to be a derisive one. Historians have fabricated the following story: As Taylor was constructing his first such building, St. Mary's Church, in 1833, skilled carpenters looked on at the comparatively thin framing members, all held together with nails, and declared this method of construction to be no more substantial than a balloon. It would surely blow over in the next wind! Though the criticism proved baseless, the name stuck.

Although lumber was plentiful in 19th century America, skilled labor was not. The advent of cheap machine-made nails, along with water-powered sawmills in the early 19th century made balloon framing highly attractive, because it did not require highly-skilled carpenters, as did the dovetail joint
Dovetail joint
A dovetail joint or simply dovetail is a joint technique most commonly used in woodworking joinery. Noted for its resistance to being pulled apart , the dovetail joint is commonly used to join the sides of a drawer to the front....

s, mortises and tenons
Mortise and tenon
The mortise and tenon joint has been used for thousands of years by woodworkers around the world to join pieces of wood, mainly when the adjoining pieces connect at an angle of 90°. In its basic form it is both simple and strong. Although there are many joint variations, the basic mortise and tenon...

 required by post-and-beam construction. For the first time, any farmer could build his own buildings without a time-consuming learning curve.

It has been said that balloon framing populated the western United States and the western provinces of Canada. Without it, western boomtowns certainly could not have blossomed overnight. It is also a fair certainty that, by radically reducing construction costs, balloon framing improved the shelter options of poorer North Americans. For example, many 19th century New England
New England
New England is a region in the northeastern corner of the United States consisting of the six states of Maine, New Hampshire, Vermont, Massachusetts, Rhode Island, and Connecticut...

 working neighborhoods consist of balloon-constructed three-story apartment buildings referred to as triple deckers.

The main difference between platform and balloon framing is at the floor lines. The balloon wall studs
Wall stud
A wall stud is a vertical member in the light frame construction techniques called balloon framing and platform framing of a building's wall.-Purpose:...

 extend from the sill of the first story all the way to the top plate or end rafter
Rafter
A rafter is one of a series of sloped structural members , that extend from the ridge or hip to the downslope perimeter or eave, designed to support the roof deck and its associated loads.-Design:...

 of the second story. The platform-framed wall, on the other hand, is independent for each floor.

Balloon framing has several disadvantages as a construction method:
  1. The creation of a path for fire to readily travel from floor to floor. This is mitigated with the use of firestops at each floor level.
  2. The lack of a working platform for work on upper floors. Whereas workers can readily reach the top of the walls being erected with platform framing, balloon construction requires scaffolding to reach the tops of the walls (which are often two or three stories above the working platform).
  3. The requirement for long framing members.
  4. In certain larger buildings, a noticeable down-slope of floors towards central walls, caused by the differential shrinkage of the wood framing members at the perimeter versus central walls. Larger balloon-framed buildings will have central bearing walls which are actually platform framed and thus will have horizontal sill and top plates at each floor level, plus the intervening floor joists, at these central walls. Wood will shrink much more across its grain than along the grain. Therefore, the cumulative shrinkage in the center of such a building is considerably more than the shrinkage at the perimeter where there are many fewer horizontal members. Of course, this problem, unlike the first three, takes time to develop and become noticeable.
  5. Present day balloon framing buildings have considerably higher heating costs, due to the lack of insulation separating a room from its exterior walls.


Since steel is generally more fire-resistant than wood, and steel framing members can be made to arbitrary lengths, balloon framing is growing in popularity again in light gauge steel stud construction. Balloon framing provides a more direct load path down to the foundation. Additionally, balloon framing allows more flexibility for tradesmen
Tradesman
This article is about the skilled manual worker meaning of the term; for other uses see Tradesperson .A tradesman is a skilled manual worker in a particular trade or craft. Economically and socially, a tradesman's status is considered between a laborer and a professional, with a high degree of both...

 in that it is significantly easier to pull wire, piping and ducting without having to bore through or work around framing members.

Platform framing

In Canada
Canada
Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

 and the United States, the most common method of light-frame construction for house
House
A house is a building or structure that has the ability to be occupied for dwelling by human beings or other creatures. The term house includes many kinds of different dwellings ranging from rudimentary huts of nomadic tribes to free standing individual structures...

s and small apartment buildings as well as other small commercial buildings is platform framing. In builder parlance platform framing might also nowadays be called (only partly correctly) 'stick framing' or 'stick construction' as each element is built up stick by stick, which was also true in the other stick framing method, in the obsolescent, labor intensive, but previously fashionable balloon framing method, wherein the outside walls were erected, headers hung, then floor joists were inserted into a box made of walls.

In contrast, in platform framing a floor box and joists making up the platform is built and placed on a supporting under structure (Sill plate
Sill plate
A sill plate or sole plate in construction and architecture is the bottom horizontal member of a wall or building to which vertical members are attached. Sill plates are usually composed of lumber. It usually comes in sizes of 2×4, 2×6, 2×8, and 2×10. In the platform framing method the sill plate...

s, header
Header
Header may refer to: Computers and engineering* Header , supplemental data at the beginning of a data block** E-mail header** HTTP header* Header file, a text file used in computer programming...

s, or beams) where it sits flat and gets fastened down against wind lifting with galvanized metal tie straps. Once the boxed floor platform is squared, leveled and fastened then subfloor
Floor
A floor is the walking surface of a room or vehicle. Floors vary from simple dirt in a cave to many-layered surfaces using modern technology...

, wall
Wall
A wall is a usually solid structure that defines and sometimes protects an area. Most commonly, a wall delineates a building and supports its superstructure, separates space in buildings into rooms, or protects or delineates a space in the open air...

s, ceiling
Ceiling
A ceiling is an overhead interior surface that covers the upper limit of a room. It is generally not a structural element, but a finished surface concealing the underside of the floor or roof structure above....

s, and roof
Roof
A roof is the covering on the uppermost part of a building. A roof protects the building and its contents from the effects of weather. Structures that require roofs range from a letter box to a cathedral or stadium, dwellings being the most numerous....

 are built onto and above that initial platform, which can be repeated floor by floor, without the slow downs and dangerous necessities of fastening and leveling rough-sawn joists of a new floor together to the walls from ladders extending one or even two stories
Storey
A storey or story is any level part of a building that could be used by people...

 up.

Generally, the flooring ('platform') is constructed then the walls built on top of that layer, then another atop that, and so forth making for quick efficient labor saving construction methodologies and those have quickened further as technologies such as joist hangers have been developed to speed and enhance the technology. The methods and techniques have become so common and pervasive that even Skyscraper
Skyscraper
A skyscraper is a tall, continuously habitable building of many stories, often designed for office and commercial use. There is no official definition or height above which a building may be classified as a skyscraper...

s use a modified form of platform framing techniques and indeed the same tools and technologies once construction builds the initial structural skeleton
Skeleton
The skeleton is the body part that forms the supporting structure of an organism. There are two different skeletal types: the exoskeleton, which is the stable outer shell of an organism, and the endoskeleton, which forms the support structure inside the body.In a figurative sense, skeleton can...

. Once the platform floor is laid down, the builder's crew can with chalk line, rule and pencil directly transfer an outline of the exterior and interior walls, their openings and relative locations with ease and precision from the plans or builders blue prints.

As the survey group lays down the notations and chalk lines, a carpenter crew can follow behind and lay down 2x4 'bottom plates' and tack them to the floor box. The topmost wall plates are cut only to the outside dimensions of the walls. Butting two other two by fours against these cut to size and fastened bottom plate allows the crew to rule across all three with square and lay out studs, cripple studs, and openings for that particular wall. The two loose studs are then quickly flipped on edge after openings are cut in, and studs added on the marks with quick reliable end nailing through the respective top and bottom plates. A few minutes later the whole wall section can be levered up and aligned in place and braced for later application of the top plates and adjoining walls.

The method provides builders options and flexibility such as when and where there's a floor level opening (doorway) the next wall section can be aligned and fastened in place separately with the top plate added then used then a lintel and cripple studding added, or the entire wall could have been cut and joined at the top all along and lifted up as one entity. In the end, the outside walls are plumbed and fastened together with 'Ell-configured reinforced corners' that provide nailing wood in the interior angles and strength to the building forming in effect wide posts at each corner and fastened lastly by overlapped top plates which stagger their joints from the ones capping each plate by which the studs are end nailed together. Each wall from top to bottom ends up with a doubled plate, studs, and a doubled plate, where structurally the doubled plates spread the weight of the roof and loading across the studs of the wall, ultimately to the foundation.

Overall, the framed structure sits (most commonly) atop a concrete
Concrete
Concrete is a composite construction material, composed of cement and other cementitious materials such as fly ash and slag cement, aggregate , water and chemical admixtures.The word concrete comes from the Latin word...

  foundation
Foundation (architecture)
A foundation is the lowest and supporting layer of a structure. Foundations are generally divided into two categories: shallow foundations and deep foundations.-Shallow foundations:...

 on pressure treated wood 'sill', or 'beam'. When on concrete, the sill plate
Sill plate
A sill plate or sole plate in construction and architecture is the bottom horizontal member of a wall or building to which vertical members are attached. Sill plates are usually composed of lumber. It usually comes in sizes of 2×4, 2×6, 2×8, and 2×10. In the platform framing method the sill plate...

 is anchored
Anchor bolt
An anchor bolt is used to attach objects or structures to concrete. There are many types of anchor bolts, consisting of designs that are mostly proprietary to the manufacturing companies. All consist of a threaded end, to which a nut and washer can be attached for the external load...

, usually with (embedded) 'J' bolts into the concrete substrate of the foundation wall. Generally these plates must be pressure treated to keep from rotting from condensing moisture. By various standards the bottom of the sill plate
Sill plate
A sill plate or sole plate in construction and architecture is the bottom horizontal member of a wall or building to which vertical members are attached. Sill plates are usually composed of lumber. It usually comes in sizes of 2×4, 2×6, 2×8, and 2×10. In the platform framing method the sill plate...

 is located a minimum 6 inches (152.4 mm) above the finished grade by the foundation design per standard builders practices, and frequently more dependent upon building codes of the relevant jurisdiction's local building codes. In North America building codes may differ not only state to state, but town to town, the tighter specification applying at all times. This distance, together with roofing overhangs, and other system
System
System is a set of interacting or interdependent components forming an integrated whole....

 factors, is most often selected both to prevent the sill-plate from rotting (due to the invasion of splashed water) as well as providing a termite barrier. The later is particularly (more or less) important than anti-rotting considerations depending upon the geographical location.

Alternatively, the room, room extension, deck or even a house can be built above concrete columns
Column
A column or pillar in architecture and structural engineering is a vertical structural element that transmits, through compression, the weight of the structure above to other structural elements below. For the purpose of wind or earthquake engineering, columns may be designed to resist lateral forces...

 U.S. builders call pier
Pier
A pier is a raised structure, including bridge and building supports and walkways, over water, typically supported by widely spread piles or pillars...

s some others call pilaster
Column
A column or pillar in architecture and structural engineering is a vertical structural element that transmits, through compression, the weight of the structure above to other structural elements below. For the purpose of wind or earthquake engineering, columns may be designed to resist lateral forces...

s, another of many term misuses common to building trade parlance. In such cases, the pier (column) is usually required to rest on bed rock or extend well below the zone of average freezing soil depth (the same as a foundation) locally, and frequently is required to also have flared out or mushroomed bottom of greater surface than that the pier top (These are called 'Big foots' in the building trade and building suppliers carry PVC molds to conserve concrete which allow a builder to satisfy area requirements and the building codes). Rigid pressure treated 'Beams' (usually doubled or tripled up wider types of 2x boards) are attached to the piers using galvanized metal brackets and serve the same function as sills in foundation supported framing.

The floors, walls and roof of a framed structure are created by assembling (using nails) consistently sized framing elements of dimensional lumber
Lumber
Lumber or timber is wood in any of its stages from felling through readiness for use as structural material for construction, or wood pulp for paper production....

 (2×4, 2×6, etc.) at regular spacings (12 in, 16 in, and 24 in on center. In older construction before lumber companies milled (machine planed
Plane
-Physical objects:* Aeroplane or airplane, a fixed-wing aircraft* Plane , a woodworking tool to smooth surfaces* Platanus, a genus of trees with the common name "plane"* Acer pseudoplatanus, a tree species sometimes called "plane"...

) all dimension lumber in the era when the thicker, stronger, rough-sawn lumber was available and common in framing sometimes the lesser known -19.2" on center (8 Sticks per eight feet)- method was used), forming stud-bays (wall) or joist-bays (floor). The floors, walls and roof are typically made torsionally stable with the installation of a plywood or composite wood skin referred to as sheathing . Sheathing has very specific nailing requirements (such as size and spacing); these measures allow a known amount of shear force to be resisted by the element. Spacing the framing members properly allows them to align with the edges of standard sheathing. In the past, tongue and groove
Tongue and groove
A strong joint, the tongue and groove joint is widely used for re-entrant angles. The effect of wood shrinkage is concealed when the joint is beaded or otherwise moulded...

 planks installed diagonally were used as sheathing. Occasionally, wooden or galvanized steel braces
Tie (engineering)
A tie, structural tie, connector, or structural connector is a structural component designed to resist tension. It is the opposite of a strut, which is designed to resist compression. Ties are generally made of galvanized steel...

 are used instead of sheathing. There are also engineered wood
Engineered wood
Engineered wood, also called composite wood, man-made wood, or manufactured board; includes a range of derivative wood products which are manufactured by binding the strands, particles, fibers, or veneers of wood, together with adhesives, to form composite materials...

 panels made for shear and bracing.

The floor, or the platform of the name, is made up of joists (usually 2x6, 2×8, 2×10 or 2×12, depending on the span) that sit on supporting walls, beams or girders within doubled outside members forming a elongated box where the outer box is nearly the same (3 inch vs. 3.5 inches) width as the support sill. At each end of the joists (which will generally span across the short distance of the rectangle. The double thick outer headers will overlap the inner box with staggered end joints allowing through plank nailing into the ends of the members sitting at right angles. If joist hangers are not used, the installation of the outer board in the headers is delayed to allow through nailing directly into the ends of the joists, also at right angle providing an additional effective length of fastener securing the joists, and still supporting the structure above with a doubled beam-like header.

That is an outer box, like a picture frame is almost always a double frame to carry the weight above downwards. The floor joists are spaced at (12 in, 16 in, and 24 in on center, depending upon the live load needs of the design—the closer the spacing and the wider the floor joist composition, the less the floor will flex.) and covered with a plywood subfloor. In the century past, 1x planks set at 45-degrees to the joists were used for the first subfloor layer, and a second layer of 1x planks set at 90-degrees to the floor cladding topped that as the upper subfloor layer. In that same era, all flooring choices were a very short menu of choices between finished wood types or ceramic tiles versus today's extensive multipage menu of manufactured flooring types.

Where the design calls for a framed floor, the resulting platform is where the framer will construct and stand that floor's walls (interior and exterior load bearing walls and space-dividing, non-load bearing partitions). Additional framed floors and their walls may then be erected to a general maximum of four in wood framed construction. There will be no framed floor in the case of a single-level structure with a concrete floor known as a slab on grade.

Stair
Stairway
Stairway, staircase, stairwell, flight of stairs, or simply stairs are names for a construction designed to bridge a large vertical distance by dividing it into smaller vertical distances, called steps...

s between floors are framed by installing stepped stringers and then placing the horizontal treads and vertical risers.

A framed roof is an assembly of rafters and wall-ties supported by the top story's walls. Prefabricated and site-built truss
Truss
In architecture and structural engineering, a truss is a structure comprising one or more triangular units constructed with straight members whose ends are connected at joints referred to as nodes. External forces and reactions to those forces are considered to act only at the nodes and result in...

ed rafters are also used along with the more common stick framing method. Trusses are engineered to redistribute tension away from wall-tie members and the ceiling members. The roof members are covered with sheathing
Plywood
Plywood is a type of manufactured timber made from thin sheets of wood veneer. It is one of the most widely used wood products. It is flexible, inexpensive, workable, re-usable, and can usually be locally manufactured...

 or strapping
Strapping
Strapping, also known as bundling and banding, is the process of applying a strap to an item to combine, hold, reinforce, or fasten it. The strap may also be referred to as strapping...

 to form the roof deck for the finish roofing material.

Floor joists can be engineered lumber (trussed, I-joist
I-joist
An engineered wood joist, more commonly known as an I-joist, is a product designed to eliminate many of the problems that occur with using conventional wood joists. Invented in 1969, the I-joist is a man made engineered wood product which has incredible strength in relation to its size and weight...

, etc.), conserving resources with increased rigidity and value. They are semi-custom manufactured allow access for runs of plumbing, HVAC, etc. and some 'common-needs' forms are pre-manufactured as semi-mass produced standard products made on a per order basis, like roofing trusses. Such products have a post-order lead time from several weeks to several months.

Double framing is a style of framing used to reduce heat loss and air infiltration. Two walls are built around the perimeter of the building with a small gap in between. The inner wall carries the structural load of the building and is constructed as described above. The exterior wall is not load bearing and can be constructed using lighter materials. Insulation is installed in the entire space between the outside edge of the exterior wall and the inside edge of the interior wall. The size of the gap depends upon how much insulation is desired. The vapor barrier is installed on the outside of the inner wall, rather than between the studs and drywall of a standard framed structure. This increases its effectiveness as it is not perforated by electrical and plumbing connections.

Materials

Light-frame materials are most often wood or rectangular steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

 tubes or C-channels. Wood pieces are typically connected with nails or screws; steel pieces are connected with nuts and bolts. Preferred species for linear structural members are softwoods such as spruce
Spruce
A spruce is a tree of the genus Picea , a genus of about 35 species of coniferous evergreen trees in the Family Pinaceae, found in the northern temperate and boreal regions of the earth. Spruces are large trees, from tall when mature, and can be distinguished by their whorled branches and conical...

, pine
Pine
Pines are trees in the genus Pinus ,in the family Pinaceae. They make up the monotypic subfamily Pinoideae. There are about 115 species of pine, although different authorities accept between 105 and 125 species.-Etymology:...

 and fir
Fir
Firs are a genus of 48–55 species of evergreen conifers in the family Pinaceae. They are found through much of North and Central America, Europe, Asia, and North Africa, occurring in mountains over most of the range...

. Light frame material dimensions range from 38 mm by 89 mm (1.5 in by 3.5 in; i.e., a two-by-four) to 5 cm by 30 cm (two-by-twelve inches) at the cross-section, and lengths ranging from 2.5 m (8.2 ft) for walls to 7 m (23 ft) or more for joists and rafters. Recently, architects have begun experimenting with pre-cut modular aluminum framing to reduce on-site construction costs.

Wall panels built of studs are interrupted by sections that provide rough openings for door
Door
A door is a movable structure used to open and close off an entrance, typically consisting of a panel that swings on hinges or that slides or rotates inside of a space....

s and window
Window
A window is a transparent or translucent opening in a wall or door that allows the passage of light and, if not closed or sealed, air and sound. Windows are usually glazed or covered in some other transparent or translucent material like float glass. Windows are held in place by frames, which...

s. Openings are typically spanned by a header or lintel that bears the weight of structure above the opening. Headers are usually built to rest on trimmers, also called jacks. Areas around windows are defined by a sill beneath the window, and cripples, which are shorter studs that span the area from the bottom plate to the sill and sometimes from the top of the window to a header, or from a header to a top plate. Diagonal bracings made of wood or steel provide shear (horizontal strength) as do panels of sheeting nailed to studs, sills and headers.

Wall sections usually include a bottom plate which is secured to the structure of a floor, and one, or more often two top plates that tie walls together and provide a bearing for structures above the wall. Wood or steel floor frames usually include a rim joist
Rim joist
In the framing of a deck or building, a rim joist is the final joist that caps the end of the row of joists that support a floor or ceiling. A rim joist makes up the end of the box that comprises the floor system....

 around the perimeter of a system of floor joists, and often include bridging material near the center of a span to prevent lateral buckling of the spanning members. In two-story construction, openings are left in the floor system for a stairwell, in which stair risers and treads are most often attached to squared faces cut into sloping stair stringers.

Interior wall coverings in light-frame construction typically include wallboard
Drywall
Drywall, also known as plasterboard, wallboard or gypsum board is a panel made of gypsum plaster pressed between two thick sheets of paper...

, lath and plaster
Lath and plaster
Lath and plaster is a building process used mainly for interior walls in Canada and the United States until the late 1950s. After the 1950s, drywall began to replace the lath and plaster process in the United States. In the United Kingdom, lath and plaster was used for some interior partition...

 or decorative wood paneling
Frame and panel
Frame and panel construction is a woodworking technique often used in the making of doors, wainscoting, and other decorative features for cabinets, furniture, and homes...

.

Exterior finishes for walls and ceilings often include plywood or composite
Composite material
Composite materials, often shortened to composites or called composition materials, are engineered or naturally occurring materials made from two or more constituent materials with significantly different physical or chemical properties which remain separate and distinct at the macroscopic or...

 sheathing, brick
Brick
A brick is a block of ceramic material used in masonry construction, usually laid using various kinds of mortar. It has been regarded as one of the longest lasting and strongest building materials used throughout history.-History:...

 or stone
Rock (geology)
In geology, rock or stone is a naturally occurring solid aggregate of minerals and/or mineraloids.The Earth's outer solid layer, the lithosphere, is made of rock. In general rocks are of three types, namely, igneous, sedimentary, and metamorphic...

 veneers, and various stucco
Stucco
Stucco or render is a material made of an aggregate, a binder, and water. Stucco is applied wet and hardens to a very dense solid. It is used as decorative coating for walls and ceilings and as a sculptural and artistic material in architecture...

 finishes. Cavities between studs, usually placed 40 – apart, are usually filled with insulation
Thermal insulation
Thermal insulation is the reduction of the effects of the various processes of heat transfer between objects in thermal contact or in range of radiative influence. Heat transfer is the transfer of thermal energy between objects of differing temperature...

 materials, such as fiberglass
Fiberglass
Glass fiber is a material consisting of numerous extremely fine fibers of glass.Glassmakers throughout history have experimented with glass fibers, but mass manufacture of glass fiber was only made possible with the invention of finer machine tooling...

 batting, or cellulose
Cellulose
Cellulose is an organic compound with the formula , a polysaccharide consisting of a linear chain of several hundred to over ten thousand β linked D-glucose units....

 filling sometimes made of recycled newsprint
Newsprint
Newsprint is a low-cost, non-archival paper most commonly used to print newspapers, and other publications and advertising material. It usually has an off-white cast and distinctive feel. It is designed for use in printing presses that employ a long web of paper rather than individual sheets of...

 treated with boron
Boron
Boron is the chemical element with atomic number 5 and the chemical symbol B. Boron is a metalloid. Because boron is not produced by stellar nucleosynthesis, it is a low-abundance element in both the solar system and the Earth's crust. However, boron is concentrated on Earth by the...

 additives for fire
Fire
Fire is the rapid oxidation of a material in the chemical process of combustion, releasing heat, light, and various reaction products. Slower oxidative processes like rusting or digestion are not included by this definition....

 prevention and vermin
Vermin
Vermin is a term applied to various animal species regarded by some as pests or nuisances and especially to those associated with the carrying of disease. Since the term is defined in relation to human activities, which species are included will vary from area to area and even person to person...

 control.

In natural building
Natural building
A natural building involves a range of building systems and materials that place major emphasis on sustainability. Ways of achieving sustainability through natural building focus on durability and the use of minimally processed, plentiful or renewable resources, as well as those that, while...

, straw bales
Straw-bale construction
Straw-bale construction is a building method that uses bales of straw as structural elements, building insulation, or both...

, cob and adobe
Adobe
Adobe is a natural building material made from sand, clay, water, and some kind of fibrous or organic material , which the builders shape into bricks using frames and dry in the sun. Adobe buildings are similar to cob and mudbrick buildings. Adobe structures are extremely durable, and account for...

 may be used for both exterior and interior walls.
The part of a structural building that goes diagonally across a wall is called a T-bar. It stops the walls from collapsing in gusty winds.

Roofs

Roof
Roof
A roof is the covering on the uppermost part of a building. A roof protects the building and its contents from the effects of weather. Structures that require roofs range from a letter box to a cathedral or stadium, dwellings being the most numerous....

s are usually built to provide a sloping surface intended to shed rain or snow, with slopes ranging from 1 cm of rise per 15 cm (less than an inch per linear foot) of rafter length, to steep slopes of more than 2 cm per cm (two feet per foot) of rafter length. A light-frame structure built mostly inside sloping walls comprising a roof is called an A-frame
A-Frame
An A-frame is a basic structure designed to bear a load in a lightweight economical manner. The simplest form of an A-frame is two similarly sized beams, arranged in a 45-degree or greater angle, attached at the top...

.

Roofs are most often covered with shingle
Roof shingle
Roof shingles are a roof covering consisting of individual overlapping elements. These elements are typically flat rectangular shapes laid in rows from the bottom edge of the roof up, with each successive higher row overlapping the joints in the row below...

s made of asphalt, fiberglass and small gravel coating, but a wide range of materials are used. Molten tar
Tar
Tar is modified pitch produced primarily from the wood and roots of pine by destructive distillation under pyrolysis. Production and trade in tar was a major contributor in the economies of Northern Europe and Colonial America. Its main use was in preserving wooden vessels against rot. The largest...

 is often used to waterproof flatter roofs, but newer materials include rubber and synthetic materials. Steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

 panels are popular roof coverings in some areas, preferred for their durability. Slate
Slate
Slate is a fine-grained, foliated, homogeneous metamorphic rock derived from an original shale-type sedimentary rock composed of clay or volcanic ash through low-grade regional metamorphism. The result is a foliated rock in which the foliation may not correspond to the original sedimentary layering...

 or tile
Tile
A tile is a manufactured piece of hard-wearing material such as ceramic, stone, metal, or even glass. Tiles are generally used for covering roofs, floors, walls, showers, or other objects such as tabletops...

 roofs offer more historic coverings for light-frame roofs.

Light-frame methods allow easy construction of unique roof designs. Hip roofs, which slope toward walls on all sides and are joined at hip rafters that span from corners to a ridge. Valleys are formed when two sloping roof sections drain toward each other. Dormer
Dormer
A dormer is a structural element of a building that protrudes from the plane of a sloping roof surface. Dormers are used, either in original construction or as later additions, to create usable space in the roof of a building by adding headroom and usually also by enabling addition of windows.Often...

s are small areas in which vertical walls interrupt a roof line, and which are topped off by slopes at usually right angle
Right angle
In geometry and trigonometry, a right angle is an angle that bisects the angle formed by two halves of a straight line. More precisely, if a ray is placed so that its endpoint is on a line and the adjacent angles are equal, then they are right angles...

s to a main roof section. Gable
Gable
A gable is the generally triangular portion of a wall between the edges of a sloping roof. The shape of the gable and how it is detailed depends on the structural system being used and aesthetic concerns. Thus the type of roof enclosing the volume dictates the shape of the gable...

s are formed when a length-wise section of sloping roof ends to form a triangular wall section. Clerestories
Clerestory
Clerestory is an architectural term that historically denoted an upper level of a Roman basilica or of the nave of a Romanesque or Gothic church, the walls of which rise above the rooflines of the lower aisles and are pierced with windows. In modern usage, clerestory refers to any high windows...

 are formed by an interruption along the slope of a roof where a short vertical wall connects it to another roof section. Flat roofs, which usually include at least a nominal slope to shed water, are often surrounded by parapet walls with openings (called scupper
Scupper
A scupper is an opening in the side walls of an open-air structure, for purposes of draining water. They are usually placed at or near ground level, and allow rain or liquids to flow off the side of the open-air structure, instead of pooling within the walls.There are two main kinds of scupper:#...

s) to allow water to drain out. Sloping crickets are built into roofs to direct water away from areas of poor drainage, such as behind a chimney at the bottom of a sloping section.

Structure

Light-frame buildings are often erected on monolithic
Monolithic architecture
Monolithic architecture is a style of construction in which a building is carved, cast or excavated from a single piece of material. The most basic form of monolithic architecture is the monolith, such as the monolithic churches of Lalibela, Ethiopia or the Pancha Rathas in India.Buildings with a...

 concrete slab foundations that serve both as a floor and as a support for the structure. Other light-frame buildings are built over a crawlspace or a basement
Basement
__FORCETOC__A basement is one or more floors of a building that are either completely or partially below the ground floor. Basements are typically used as a utility space for a building where such items as the furnace, water heater, breaker panel or fuse box, car park, and air-conditioning system...

, with wood or steel joists used to span between foundation walls, usually constructed of poured concrete or concrete blocks.

Engineered components are commonly used to form floor, ceiling and roof structures in place of solid wood. I-joist
I-joist
An engineered wood joist, more commonly known as an I-joist, is a product designed to eliminate many of the problems that occur with using conventional wood joists. Invented in 1969, the I-joist is a man made engineered wood product which has incredible strength in relation to its size and weight...

s (closed-web trusses) are often made from laminated woods, most often chipped poplar wood, in panels as thin as 1 cm (0.4 in), glued between horizontally laminated members of less than 4 cm by 4 cm (two-by-twos), to span distances of as much as 9 m (29.5 ft). Open web trussed joists and rafters are often formed of 4 cm by 9 cm (two-by-four) wood members to provide support for floors, roofing systems and ceiling finishes.

See also

  • Framer
    Framer
    A framer is a carpenter who assembles the major structural elements of a wood-framed building. Framers build walls out of studs, sills, and headers; build floors from joists and beams; and frame roofs using ridge poles and rafters....

  • Steel frame
    Steel frame
    Steel frame usually refers to a building technique with a "skeleton frame" of vertical steel columns and horizontal -beams, constructed in a rectangular grid to support the floors, roof and walls of a building which are all attached to the frame...

  • Tessellated roof
    Tessellated roof
    In architecture a tessellated roof is a frame and a self-supporting structural system.A simple ridged roof may inside be a tessellated system, it is built in many types of buildings...

  • Timber framing
    Timber framing
    Timber framing , or half-timbering, also called in North America "post-and-beam" construction, is the method of creating structures using heavy squared off and carefully fitted and joined timbers with joints secured by large wooden pegs . It is commonplace in large barns...

  • Light Timber Construction (Schools)
    Light Timber Construction (Schools)
    Light Timber Construction was the name given to a standardised architectural design used for the construction of hundreds of state school buildings in Victoria, Australia, between 1954 and 1977. LTC school buildings were designed for speed of construction, uniform appearance and low cost...


External links

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