Building framing is classified into two types: heavy-frame construction (heavy framing) when the vertical supports are few and heavy, as in timber framing, pole building framing, or steel framing, and light-frame construction (light-framing) when the supports are numerous and smaller, as in balloons. Heavy frames are often required for large buildings because they can be built stronger without using much material. They are also used when a building will be standing for a long time like storage facilities or factories because concrete or cement-based materials harden over time and need to be replaced periodically.
The amount of material used in construction is called its "weight". The weight of a structure is the sum of its individual component parts, including their weight. For example, if a beam is made out of 2x4s and has a weight of 50 pounds, then it is a heavy beam. The weight of a structure is usually expressed in pounds per square foot (psf).
Heavy beams are commonly used in large buildings because they can be easily obtained from a workyard and transported to the site where they are needed most, thus reducing the number of workers needed for their installation. Also, they can be cut to size at the workyard with a power saw or other cutting equipment and then transported to their final positions before being joined together with bolts or screws.
Heavy framing is made up of frame members that are at least 6 inches in length (timber construction). Built-up roof trusses span long, unsupported regions between walls. They are too heavy for standard 2x4s to bear easily.
The word "heavy" is used to describe the framing because it can make a large difference in the ability to move a wall or ceiling later. Heavy framing is more stable than light framing and can be used where greater strength is needed.
In addition to being taller, heavier framing creates a box with which to work. It allows you to insert blocking between the studs to keep out wall surfaces during construction.
Finally, heavy framing makes it easier to handle large or awkwardly shaped items during remodeling projects or building additions. For example, when adding on to a house, builders use either light framing which requires buttressing each beam with timbers before you can push them against the wall (which is expensive) or they use heavy framing so they don't have to bother with this step.
For these reasons, heavy framing is necessary for proper construction of most buildings over 7 feet tall.
However, lighter framing is acceptable in small buildings and homes if they do not have major structural problems or need extensive remodeling.
Platform framing is the most popular framing style in modern residential building, in which each storey is constructed on top of the preceding one. One-story platforms are generally framed with eight- or nine-foot-high stud walls sitting on a subfloor—the platform. Two-story and larger structures use multiple layers of framing to create a strong base for the house. The upper floors are then supported by columns attached to the side of the lower floor frame.
In beam framing, the floor is made up of large beams that span the room. On the first floor, these beams are usually tied together at their ends to form a flat surface called a floor joist. Second-floor beams are usually not tied, but rather have holes drilled into them for attaching door and window trim. This type of framing is common in older buildings as well as some new constructions.
In panel framing, the floor is made up of large panels that are fixed to the wall with screws or nails. On the first floor, these panels are usually formed by ripping out the bottom plate of a piece of plywood (or other material) that is usually 8 feet by 10 feet or larger. Second-floor panels are usually not torn out but instead have openings cut into them for doors and windows. This type of framing is commonly used for apartment buildings and small houses.
To handle lateral and gravitational stresses, a frame structure is made up of a beam, a column, and a slab. These structures are often utilized to resist significant moments caused by applied loading. A frame is also used to connect two other structures, such as a wall to a roof, or a floor to a ceiling.
The main purpose of a frame is to provide stability for its surrounding elements. It does this by distributing stress evenly so that no single point is likely to fail. A frame is also useful when you need to connect two very different things: for example, a wall to a roof. A frame does this by acting as a kind of "intermediate structure" between them. It takes pressure off of any one element and transfers it to the others, which allows them to support each other.
A frame is also useful when you want to protect something delicate from damage caused by heavy objects falling on it. For example, if you were to put a glass window in your house then it would be important to prevent it from being damaged by fallen trees or bricks. A frame does this by preventing objects from hitting the window directly.
Finally, a frame is useful when you want to create some space inside your home for easier storage or access.
The major distinction between a load-bearing structure and a framed structure is the components that carry and transfer the weight to the subsoil. Load-bearing members in a load-bearing structure are walls, whereas load-bearing elements in a framed structure are beams and columns. The wall of a house can be considered a load-bearing element because it supports the roof and other walls. The floor and ceiling joists in a room are not load-bearing; they provide structural support but do not bear any weight themselves. The main beam of a building carries its weight and transfers it to the foundation or ground slab. Other beams may provide additional support for high-load areas of the building.
Load-bearing elements are important in structures such as bridges, buildings, and vehicles because they prevent these structures from collapsing under their own weight. In addition, the elements contribute to the stability and safety of these structures by preventing them from being too heavy or rigidly anchored at one location. For example, without a wall to support the weight of an elevator car, it would collapse in on itself like a cardboard box when it reaches its maximum capacity. This is because its weight is too much for the thin metal used for the side panels of the car. A wall keeps the elevator car safe and stable even if more people get on board.
Rigid-frame building structures provide rotational stability, which improves how they handle vertical loads and, as a result, extends the overall structure's longevity. The term is derived from the classification of beam-to-column connections. In a rigid frame building, the members connecting the beams to the columns are called stiffeners. They must be rigid so they do not transfer the load to adjacent non-load-bearing walls or ceilings.
In early buildings, horizontal boards were used instead. But the first rigid frame building was constructed in 1622 by Christopher Wren when he designed St. Paul's Cathedral in London. He used wooden strips as connectors between the floor and ceiling joists (which were not then covered with wood) to provide stability against twisting forces.
The use of metal connectors became common after 1872 when Henry Ford introduced the steel frame construction method into America. Prior to this time, most buildings were made with timber frames because it was much cheaper than steel frames. But the quality of timber available on the market at that time was very poor and many buildings collapsed during heavy storms or while people were inside of them. So engineers realized they needed another way to connect the beams to the columns.
Henry Ford is credited with introducing the concept of using large numbers of short sections of pipe for structural members.