NCCER Carpenter key terms

Gear worn to reduce the chance of injury on the job, such as safety glasses, hard hats, gloves, hearing protection, and sturdy boots. Employers require it, and workers must inspect it and use it correctly for each task.

Systems and practices that keep workers from falling from heights, including guardrails, personal fall-arrest harnesses, lanyards, anchor points, and safe ladder use. It is required above specified heights set by OSHA and company policy.

Ground-fault circuit interrupter: a device that cuts power quickly when it senses current leaking to ground. It is required on temporary job-site receptacles and in wet locations to reduce the risk of electric shock.

A procedure for shutting off and securing energy sources before servicing equipment, using locks and warning tags so no one can restart the machine while a worker is exposed to moving parts or electricity.

A document supplied with a hazardous product that lists its hazards, safe handling, first-aid steps, and emergency response. Workers must know where the sheets are kept and how to read them.

A triangular layout tool that combines a try square and a protractor. It is used to mark square and angled cuts on lumber, check squareness, and find roof pitches and rafter angles quickly.

A power tool driven by compressed air that drives nails into wood. Operators must wear eye protection, keep fingers clear of the trigger, disconnect the air before clearing jams, and never point the tool at people.

The complete set of scaled drawings used to build a project, including plans, elevations, sections, and details. They work together with written specifications to describe the size, materials, and location of all work.

The ratio between a distance on a drawing and the real distance it represents, such as one-quarter inch equals one foot. Reading the stated scale lets a carpenter convert drawing dimensions into actual field dimensions.

A fixed, known elevation point on or near the site that is marked and protected, from which all other elevations are measured. Builders use it to set footing, floor, and finish grades accurately.

Temporary horizontal boards set beyond the building corners and connected by string lines. They mark foundation and wall lines and allow the layout to be re-established after excavation and before concrete work.

Temporary molds, usually wood or metal panels, that hold fresh concrete at the desired shape and position until it cures. Forms must be strong, tight, braced, and coated so they strip cleanly.

Steel reinforcing bars placed in concrete to carry tension forces. Bars are tied in place at laps, held at the specified cover with supports, and sized and spaced as shown on the drawings.

A planned groove or saw cut in a concrete slab that forces shrinkage cracks to form along a straight, out-of-sight line. It is typically cut to about one-quarter of the slab thickness.

A threaded steel bolt set into concrete to tie down sills, plates, or equipment. Its location, diameter, and projection must be checked before the concrete sets because mistakes are costly to correct.

The pressure-treated member fastened to the foundation that forms the base of a wood-frame wall. It is anchored with bolts and sealed to the concrete to resist moisture and uplift.

A horizontal framing member that supports the subfloor and floor loads and transfers them to girders, beams, or walls. Size, grade, span, and spacing are set by the plans and building codes.

A large beam that supports floor joists and carries their loads to posts or foundation walls. Girders may be solid lumber, built-up members, or engineered beams and must bear properly at each end.

The structural panel layer fastened over floor joists to create the flat surface that receives finished flooring. Panels are glued and nailed, edges are supported, and joints are staggered.

The full-height stud located directly against each side of a rough opening. It runs from the sole plate to the top plate and supports both the header and the wall above the opening.

A shorter stud, also called a trimmer, that sits under the end of a header and rests on the sole plate. Paired with a king stud, it carries the header load down to the floor.

A horizontal member spanning the top of a door or window opening that carries the loads above it and transfers them to the jack and king studs on each side of the opening.

Spacing measured from the center of one framing member to the center of the next. It is used to lay out studs, joists, and rafters so panel edges land on framing consistently.

Solid material installed inside concealed wall, floor, and ceiling cavities to stop or slow the spread of fire and smoke. Codes require it at specific locations, such as between floors and at soffits.

A sloping framing member that forms the roof and supports roof sheathing and covering, running from the ridge or a hip down to the wall plate. Its length and cuts come from the roof pitch and span.

The horizontal member at the peak of a roof to which the upper ends of opposing rafters are nailed. It aligns the rafters and holds them in place but is not itself a structural beam.

A seat cut combined with a plumb cut and notched into the lower end of a rafter so the rafter sits flat on the wall plate. The notch depth is limited so the rafter is not weakened.

A horizontal member connecting opposing rafters above the wall plate, usually in the upper third of the roof. It resists rafter spread and helps tie the roof frame together.

The finished board fastened to the ends of rafters or trusses along the roof edge. It supports the gutter, closes off the roof edge, and gives the eave a straight, finished appearance.

Thin metal or plastic material installed to shed water at joints and penetrations such as roof valleys, wall intersections, chimneys, and windows. It is layered with the weather barrier so water drains outward.

The slope of a roof expressed as the ratio of rise to run, such as 4 in 12. Pitch determines rafter length, cut angles, headroom, and which roof coverings are permitted.

Gypsum panels fastened to framing to form interior wall and ceiling surfaces. Panels are screwed or nailed in place, joints are taped and finished with compound, and the surface is sanded before painting.

A metal or plastic strip placed over outside drywall corners to protect the edge and provide a straight guide for finishing. It is fastened in place, then covered with joint compound and sanded.

Trim installed along the bottom of an interior wall where it meets the floor. It protects the wall finish, hides the flooring gap, and is mitered or coped at inside and outside corners.

Trim that surrounds and finishes the edge of a door or window opening, covering the gap between the frame and the wall. It is fitted with mitered or coped joints and nailed to the framing.

The framed opening in a wall that is made larger than the door or window unit so the unit can be leveled, plumbed, and shimmed into position. Its size follows the manufacturer's instructions.

A thin wedge of wood or plastic used to fill gaps and adjust a unit until it is plumb, level, and square. Shims are placed at hinge and lock points and behind the frame.

The frame parts lining the sides and top of a door opening, including the head jamb and side jambs with stops. The jamb supports the hinges and strike plate and receives the casing.