The vertical framing members used to frame walls are known as studs. They are usually made of 2x4 lumber, but some homes and many businesses use metal studs instead of wood.

In the United States, the Occupation Safety and Health Administration, or OSHA, sets standard for workplace safety, with special standards aimed at the construction industry. Employers who fail to follow OSHA guidelines may be subject to heavy fines or even criminal charges.

Sheet metal ductwork is used to transport air throughout the home. These ducts are used for heating, cooling and ventilation, and form an integral part of the HVAC system.

Wooden blocking is installed within wall cavities before the walls are completed. This blocking allows you to hang a heavy object, like a fire extinguisher or television, so that it will stay safely in place.

An I-beam, which is so named because it looks like a letter I when viewed from the side, is a steel beam that serves as a major structural support in many buildings. It consists of a single web in the center, with two caps -- called flanges -- at either end.

Every construction worker should be aware of egress, or exit requirements. These standards are designed to allow occupants to safely exit a building or home in the event of an emergency. If you're building a basement bedroom, for example, you'll often be required to add a window as a second means of egress.

Sticking to the schedule and completing the job when you promised is critical for construction industry success. Not only will it help you keep getting work, but it will allow you to avoid liquidated damages -- hefty fines levied on firms that fail to finish on time.

Spackle is a genericized trademark for a popular type of drywall putty. Similar to joint compound, it's ideal for filling holes in drywall, and has been used in construction since the 1920s.

All drywall has some fire resistance thanks to its gypsum core. Type X drywall has special additives included in the core to enhance fire-resistance, making it ideal for applications such as a garage wall or ceiling.

The National Fire Protection Association, or NFPA, develops guidelines for fire safety in the building trades. Construction workers should not only be familiar with the acronym, but also with some basic NFPA guidelines used in the field.

Flashing is the metal or rubber trim used to seal penetrations around the roof and keep water out. It can be used around chimneys, pipes, vents, windows, doors or any other openings where sealing is required.

Look at almost any construction drawing and you'll see the term AFF. This is an abbreviation for "Above Finished Floor" that tells you how far above the floor an item should be installed.

Grout, a spreadable liquid made from sand, water and other elements, is most often used when installing tile. The grout fills in the gaps between the tiles to keep them stable and secure.

As-builts are a fact of life in the construction trade. This is the term used to describe a set of drawings maintained by each trade. This set includes markups that show changes as to how the structure was actually built, and may differ significantly from the original plans.

Mortar is a thick paste made from sand, water and concrete. When layered between rows of brick or block, it holds the units together to form a solid and durable structure.

The Americans with Disabilities Act, or ADA, affects every trade on a construction site. This set of federal laws specifies how a structure must be built to allow safe and equal access for people with disabilities. All construction workers should be familiar with ADA and its requirements.

DWV is an abbreviation that stands for drain, waste vent piping. These pipes carry wastewater, sewage and sewer gases safely out of a home or building.

An RFI, or request for information, is an official request for additional information or clarification. Once it's answered by the architect or engineer who designed the project, it becomes an official part of the project plans and specs.

Aggregate is used in many types of construction products and processes, from concrete to asphalt. This material consists of various particles, including gravel, stone, sand and even recycled concrete or crushed rock.

An addendum is any official change made by the owner of a project after the bid has been completed. This could include a major change, like additional square footage, or something simpler -- like a change from ceramic tile to wood flooring.

Material Safety Data Sheets are a critical part of any construction site. Known as MSDS, they reveal important information about each chemical used on the job, and are designed to keep workers and occupants safe.

A chase is a vertical or horizontal void hidden within a building. It can be built around a flue, a pipe riser, an air channel or other system to allow the building to function while maintaining a clean and neat appearance.

Rather than speaking about whether something is at ground level, construction workers use the term grade. An item buried under the soil is below-grade, while certain elements may be installed above-grade.

Heating, ventilation and air conditioning, or HVAC, is a series of systems to maintain proper, safe and comfortable airflow in the home. It consists of a heating unit, like a furnace or boiler, combined with a central cooling system or heat pump, plus ductwork to carry the air through the building.

While studs run vertically, joists run horizontally to structurally support a home. They generally rest on larger members, such as girders or beams, for extra support.

If you plan to install roofing, you have to know how to properly measure and order material. Roofing is measured by the square, with one square equal to 100 square feet of material.

A header is a horizontal framing member that passes over a door or window. The vertical portions of a door frame are known as jambs.

A louver is a panel with slits cut into it for ventilation purposes. Some are installed on the exterior of a building, while others go indoors -- such as on an interior closet door.

Construction crews are often required to included operations and maintenance manuals as part of their project closeout submission. These manuals teach building operators how to run and maintain all systems once the contractor has moved on and left the site.

On most construction sites, the project owner holds back a portion of each contractor's pay -- known as retainage -- until the work is complete. This may amount to 5 to 10 percent of each subcontract, but varies by project.

Up until the 1940s, builders used elaborate lathe and plaster systems to construct walls. Since then, drywall has become the material of choice. Made from pressed gypsum and heavy paper, these sheets of material are installed, sanded and painted to create smooth, even wall surfaces.

A pigtail is the domain of the electrician. It consists of a pair of wires connected to a single device.

The term OC is very common on construction drawings. It stands for on center, and tells an installer that measurements should be taken from the center of one component to the center of the next one, rather than from either edge.

Oriented strand board, or OSB, is a type of sheet wood similar to plywood. Made from layers of wood strands and glue, it's used to frame walls, floors and ceilings.

Construction pros know that lumber is measured and ordered using board feet. One board foot is equal to 144 cubic inches of wood, or a section of wood measuring 12 inches by 12 inches by 1 inch.