The ABCs of construction

As with so many professions, the construction trades are filled with an alphabet soup of abbreviations, so you might be a bit confused at your local home center or lumber yard.

Here's a roundup of some of the more common abbreviations you're likely to run into.

ABS: acrylonitrilebutadiene-styrene, the chemical makeup of a black, plastic-composite plumbing pipe used extensively for drain, waste and vent systems.

AC: alternating current, the most common method of delivering electricity in North America.

ADA: Americans with Disabilities Act, which sets certain accessibly guidelines for construction.

Ah: ampere hour (or, more commonly, amp hour), a common rating for rechargeable batteries. It's a unit of electrical charge, equal to a steady current of one ampere flowing for one hour.

AWG: American Wire Gauge, the U.S. standard for the size of various types of wire, including electrical wire.

bd. ft. (also bf): board foot, the standard way of measuring most types of lumber. It's equal to a board that's 1 inch thick, 12 inches wide, and 12 inches long.

BTU: British Thermal Unit, a standard unit for the measurement of heat. One BTU is about equal to the heat given off by a kitchen match.

CAD: computer-aided (or -assisted) drafting.

cf: cubic foot (or feet).

CFM: cubic feet per minute, a measurement of how fast air moves.

CFS: cubic feet per second.

ci: cast iron.

cip: cast iron pipe.

cl: center line.

cmu: concrete masonry unit, such as a concrete block.

CPVC: chlorinated polyvinyl chloride, similar to PVC but significantly more flexible and able to withstand higher temperatures.

cy: cubic yard.

d: penny, a common designation for the size of nails.

D: diameter.

db: decibel, a standardized unit of measurement for sound or noise.

DC: direct current, as from a battery.

DWV: drain, waste and vent, the system of plumbing pipes used in the removal of liquid and solid waste from a building, and the venting of sewer gases.

ea: each.

FIP: female iron pipe, referring to standard metal and plastic plumbing pipe fittings with the threads on the inside.

GFCI: ground fault circuit interrupter, an electrical device that senses a fault in the electrical system and shuts down power to that device.

GPF, LPF: gallons per flush (or liters per flush), a rating of how much water a toilet uses.

GPH, LPH: gallons per hour (or liters per hour), a rating of how much water an appliance, fixture or other item uses.

hp: horsepower, a rating of the power output of an electric motor.

HVAC: heating, ventilating and air conditioning.

id: inside diameter, typically referring to a pipe or duct.

KD: knocked down, which refers to furniture or other items that are sold in pieces that are ready to assemble.

kw: kilowatt, a unit of electrical measurement equal to 1,000 watts.

kwh: kilowatt-hour. This is the common measurement for how electricity is sold, and is equal to 1,000 watts of electricity used for one hour.

MDF: Medium Density Fiberboard, a building material made from wood fibers and resin formed under heat and pressure into sheets, boards and trim.

MIP: male iron pipe, referring to standard metal and plastic plumbing pipe and pipe fittings with the threads on the outside.

NC, NF: National Coarse and National Fine, two common designations of thread size for nuts, bolts and other threaded objects.

NPT: National Pipe Thread, a common U.S. standard for tapered threads on plumbing pipe and fittings.

NTS: not to scale, indicating a drawing that has not been drawn to a specific scale.

oc: on-center, designating the distance between the centers of two framing members.

od: outside diameter, typically referring to a pipe or duct.

OSB: Oriented Strand Board, a building material made from thin strands of wood and resin, formed under heat and pressure into sheets and boards.

PEX: cross-linked polyethylene, often used for flexible domestic water piping and hydronic radiant heating.

PSI: pounds per square inch, a rating of pressure.

PT: pressure-treated, a chemical treatment process applied to lumber as a preservative.

PVC: polyvinyl chloride, a widely used plastic composite material.

R: radius.

RO: rough opening, a framed opening that is specifically sized to receive a finished item such as a door, window, or skylight.

RPM: revolutions per

minute, a measure of rotational speed.

S4S: surfaced four sides, referring to lumber.

SF, SY: square foot and square yard.

T&G: tongue and groove, a method of milling interlocking lumber.

WC: water closet (toilet).

WH: water heater.

Wx: weatherstripping.