Term Definition
Oak Floor 1 like
A popular type of flooring, generally fitted with small tongue and groove oak strips
Oak Veneer 1 like
A thin oak layer glued to another wood to produce a decorative facing; commonly seen as white oak and red oak
Oatmeal Paper 0 likes
Wallpaper created by scattering sawdust over a surface with glue on it
OB 1 like
Octave Band
Obelisk2 likes
A stone pillar, often a monument with a square base and oblique sides that taper like a pyramid to form a pointed top
Oblique 2 likes
An angle; not parallel or perpendicular; sloping
Oblique Slip Fault 1 like
A combination of faults where the movement is diagonal along the fault plane dip
Obscure Glass1 like
obscure glass
Glass that transfers light but which can’t be seen through
Obsolescence 2 likes
Not useful any longer; out of date
Obtuse Angle 2 likes
Angle between 90 degrees and 180 degrees in size
Obtuse Triangle 2 likes
A triangle with one angle that is more than 90 degrees
OC 1 like
On center; describes the spacing of framing elements from the centers of adjacent members in a building; also seen as O/C
See Oxygen Cutting
Occupancy 2 likes
The rate of occupation of a place
Use of a building, such as a school, restaurant, residence or office
Occupancy Importance Factor (I) 0 likes
Building code terminology used to identify important occupancies
Occupational Safety & Health Administration (OSHA) 0 likes
U.S. Department of Labor/OSHA, 200 Constitution Avenue, NW, Washington DC, Tel: (202) 219-7725, URL: www.osha.gov
Ochre 2 likes
A reddish or yellowish earth pigment made from iron ore, employed in paint
Octyl Alcohol-Ethyl Hexanol 2 likes
Chemical in absorption machines that diminishes the absorber’s surface tension
Oculus 1 like
A circular or eye-shaped opening in a dome
A round window
OD 1 like
Outside Diameter
Odor 1 like
A smell; may be pleasant or unpleasant
Off Cycle 0 likes
When a system is not functioning
Off-Site 0 likes
Anything not on the building or job site
Offer 1 like
To try to provide something that may be accepted or refused
Offeror 1 like
The person who makes an offer
Office 2 likes
A room or building in which professional or business activities take place
Office Building 0 likes
A building containing several business offices
Office Cubicle 1 like
A compartment with fixed or movable walls which houses a person who works in an office
Office Park 3 likes
A prearranged group of office buildings with shared management, landscaping, parking, and other facilities
Office Partition2 likes
office partition
Portable interior wall that separates an office area
Office Safe1 like
office safe
A strong container with a lock that secures money or valuables in an office; usually fire-resistant
Office Trailer 2 likes
A vehicle used to conduct business activities on a job site
Offset 1 like
Sudden bend in a straight bar or pipe to avoid obstruction
Offset Cabinet Construction 1 like
Constructing cabinets so the back corners of the doors and drawer fronts overlap the face frame and hide the joint
Offset Hinge2 likes
offset hinge
A 90 degree offset hinge that moves the center of a door’s rotation
OG 0 likes
Ogee 0 likes
A decorative curved section of a moulding, partially convex and partially concave, like an elongated flat S
Ogee Molding 3 likes
A molding with a modified flat S-shaped profile
Ogee Roof 0 likes
An architecturally designed roof inspired by Eastern culture
Ogive 1 like
An arch with an apex
Ohm (R) 0 likes
Measures the resistance of an electrical current; occurring when a volt creates an ampere of current to flow
Ohmmeter1 like
This instrument calculates resistance measured in ohms
Ohms Law 2 likes
The electrical law that defines the ampere, voltage and resistance relationship; equation: Amperes (I) x Ohms (R) = Volts (V)
Oil Absorption 0 likes
The measure of the rate at which oil absorption occurs in pigments
Oil Base Caulking 2 likes
Distributed by tube, caulking is created from resins and oil substances
Oil Binding 1 like
An occurrence caused by a layer of oil above a liquid refrigerant whereby the refrigerant is unable to evaporate at the usual pressure and temperature
Oil Burner Nozzle1 like
oil burner nozzle
A device that sprays a mist of atomized fuel oil; the combustion properties of the fuel are enhanced
Oil Colors 1 like
A paste derived from crushing colors in linseed oil
Oil Fired Boiler 3 likes
A vessel in which oil is heated and sent to a pressurized nozzle, from which it is then dispensed as a mist and lit via electric spark
Oil Furnace3 likes
oil furnace
A furnace used to burn oil to produce heat
Oil Length 0 likes
A measurement used to grade varnish by oil length by calculating the gallons of oil present in 100 pounds of resin; shortoil varnish is weaker than long-oil varnish; a common long-oil varnish is spar varnish, while a common shortoil varnish is rubbing varnish
Oil of Vitriol 3 likes
See Sulphuric Acid
Oil Paint2 likes
oil paint
Paint comprised of oil that dries
Oil Separator2 likes
oil separator
Oil is removed from gaseous refrigerants with this device
Oil Soluble 0 likes
Ability to be dissolved when exposed to oil
Oil Stain 0 likes
A stain for wood which is comprised of dyes that are oil soluble and solvents like turpentine; will penetrate wood pores and may bleed
Oil Switch1 like
oil switch
Typically fitted in a vent pipe, this switch or relay allows the burner to be turned off within a 45 second time period when a stack is unable to reach a fixed temperature following the start of the motor
Oil Tank 1 like
The storage vessel in which heating oil is held for use in the future by a furnace system that burns oil or an oil burner
Oil Varnish 3 likes
A varnish created by the combination of hard resin, drying oil, and a drier that has been thinned with an unstable solvent; evaporation dries the solvent following application, then as a result of oxidation, the oil dries
Oil-Canning 1 like
Deformation of metal panels made of thin-gauge which are attached to prevent normal thermal passage
Oil, Refrigeration 0 likes
See Refrigeration Oil
Oilcloth Varnish 0 likes
Varnish which is usually elastic and extremely flexible
Oilstone 0 likes
A piece of whetstone employed generally with oil
Oiticica Oil 1 like
A drying oil extracted from the oiticica tree nut
Old English Bond 0 likes
See English Bond
Old Growth 2 likes
Timber obtained from a mature forest; the trees are grown mostly or completely alongside their counterparts; the wood is usually straight and untangled
Olefin 0 likes
A synthetic polymer which is long-chained made of minimum 85 percent by of propylene, ethylene or other olefin components by weight; polypropylene has been manufactured as fiber for carpets
Olefin Plastics 1 like
Products of plastic nature based on resins produced from a high amount of olefins by weight; the most commonly found olefin plastics in pipe are polybutylene, polyethylene and polypropylene
Oleoresin 4 likes
A mixture of resin and an essential oil which comes from plants like softwoods
Oleoresinous Varnish 1 like
A varnish made of resin or gum mixed in a drying oil that solidifies as it mixes with the oxygen in air
Olive Knuckle Hinge 2 likes
A hinge, paumelle in nature, with knuckles that produce an oval shape
On Center (O/C) 2 likes
Also referred to as center to center
On the Stump 0 likes
See Standing Timber
On-Site 0 likes
Items and activities occurring on the job site
One Piece Toilet3 likes
one piece toilet
A toilet in which the water tank and the bowl are molded in a single piece of vitreous china for aesthetic purposes and quiet functioning
One-Family Dwelling 2 likes
A place of dwelling consisting of only a single dwelling
One-Way 2 likes
In a single direction only
One-Way Action 1 like
Structural effect of a slab between two bearing walls or between two parallel beams
One-Way Concrete Joist System 2 likes
A strong framing system made of concrete where concrete joists are spaced near each other between parallel beams or bearing walls
One-Way Glass3 likes
one-way glass
See Transparent Mirror
One-Way Solid Slab 1 like
A concrete roof slab or floor set between parallel beams or walls, with structural reinforcement in one direction
Opacity 2 likes
Lacking transparency, such as in paint
Opaque 1 like
Lacking transparency; not able to be seen through
Opaque Glaze 1 like
A glaze that is not transparent, with or without color
Open Bid/Estimate 2 likes
A person or entity requests bids or estimates from service providers prior to qualifying them. Contractors can see and bid on project-specific information in the request for proposal (RFP)
Open Circuit 0 likes
An incomplete electric circuit disrupted via a switch, open breaker, fuse or a break in a conductor
Open Compressor3 likes
open compressor
A type of external drive compressor that is not airtight
Open Decking 3 likes
When the joists underneath a deck are visible and unprotected
Open Display Case 2 likes
An open refrigerator case for displaying items commercially; keeps contents at cool temperatures
Open Front Seat1 like
open front seat
A type of toilet seat used in public toilets; has an opening in the front
Open Hole Inspection 1 like
An engineer or municipal supervisor examines an excavation to decide upon an appropriate foundation to fill the hole
Open Listing 0 likes
A property owner makes a non-exclusive agreement with one or more real estate agents to sell or lease a property
Open Run-Around 0 likes
A way of recovering heat from exhaust air by including a fluid into the supply and exhaust air streams alternately, thus transferring latent and sensible heat
Open Time 1 like
A specific time frame in which a bond coat is able to stick to a tile and fasten the tile to a substrate
Open Type Compressor 1 like
See Compressor, Open Type
Open Type Decking 1 like
When the joists underneath a deck are visible and unprotected
Open-Graded Aggregate 2 likes
An aggregate which contains almost no mineral filler; the void spaces are quite large
Open-Graded Asphalt Friction Course 3 likes
A skid-resistant surface course that thwarts hydroplaning by enabling rainwater to drain rapidly through the course and exit the shoulder; this largely void asphalt mixture is composed mainly of coarse aggregate of a single size
Open-Grained Wood 1 like
Types of wood with sizeable pores including ash, walnut and oak; also known as Coarse Textured or Coarse-Grained
Open-Web Steel Joist 0 likes
Welded assembled steel joist employed at close distances from each other to reinforce floor or roof decking
Operable Door 2 likes
One of two doors that usually functions
Operable Part 1 like
A component of equipment or an appliance such as a coin slot or handle, used to insert or withdraw objects, start, stop or modify it
Operating Instructions 2 likes
A booklet or sheets with written directions and descriptions for the proper operation of equipment or components; provided by the manufacturer
Operating Leverage 2 likes
The ratio of the profit percentage change to the sales percentage change, measuring how revenue growth translates into growth in operating income
Operating Pressure 2 likes
Positive or negative (vacuum) pressure at which a refrigerating system normally operates
Operating Profit 1 like
A business’ earnings minus all operating expenses of a business; also known as Earnings Before Interest and Tax (EBIT) or Operating Income
Operating Room 0 likes
A hospital room especially designed and equipped for surgeries
Operation Expenses 1 like
Total expenditure for a project or business; includes the cost of products, general and administrative expenses and any indirect expenses
Opposed Blades 0 likes
A damper with two sets of blades which are connected in a way that the adjacent blades are able to open and spin in opposing directions
Option 0 likes
A choice or alternative
The right to buy, sell, or lease an item, which is kept open for consideration for a certain length of time
Optionee 0 likes
A person who is given an option
The potential buyer or lessee in a real estate option
Optionor 0 likes
The person who offers an option
In a real estate option, the owner or lessor who wants to sell or lease
Or Equal 0 likes
Used in instructions or specifications to stipulate that any substitutions must be equivalent to the original
Oral Agreement 0 likes
A contract that has been agreed to verbally rather than in writing
Orange Mineral 0 likes
Red lead which is made by baking basic carbonate white lead; mainly employed for printing ink
Orange Peel 0 likes
The pocked texture of a fired glaze which looks like an orange peel‘s surface
Defect in spray painting in which the lacquer coat does not smooth out but remains coarse; similar to when an orange peel is peeled
Orbital Sander1 like
orbital sander
A hand-held power sander that moves in a circular orbit
Ordinance 1 like
A city or a county law
Ore 1 like
Rock or other naturally occurring solid mineral that contains extractable quantities of metals or minerals of commercial value
Organic 0 likes
A chemical compound that has carbon
Consisting of hydrocarbons or derivatives thereof, or matter of biological origins
Relating to or derived from living matter
Organic Adhesive 1 like
An adhesive prepared from naturally occurring organic material that does not require more liquid or powder, used for attaching tile to back-up material with the thin set method; sets by evaporating
Organosol 3 likes
Film that has synthetic resin plasticizer and solvent; the spreading of resin particles in a mixture which has in excess of five percent volatile content
Oriel Window 2 likes
A type of bay window which is supported by corbels or brackets and projects out from a wall
Oriented Strand Board or OSB 1 like
A fabricated 4 feet by 8 feet wooden board that is composed of 1 inch to 2 inch wood chips and adhesive, and frequently used instead of plywood
Orifice 3 likes
An opening
An attachment for the nozzle of a plastering machine hose; can vary in shape and size, and may be modified to create a pattern on the plaster while it is cast onto a given surface
An opening of a furnace or boiler through which fuel is expelled
Original Contractor 0 likes
A contractor who works directly with a real property owner
Ormolu 0 likes
Gilded bronze or gold amalgam of copper, zinc and tin; used in furniture decorations and ornaments
Ornament1 like
Something used to adorn or decorate
Ornamental Facing 0 likes
A design made by positioning stone, brick, tile and other masonry items in a decorative manner in masonry
Ornamental Metal1 like
ornamental metal
A feature on a metal structure to embellish or decorate the appearance
Ornate 0 likes
Intricately adorned; extremely decorated
Orthogonal 1 like
Involving right angles; at right angles, perpendicular
Orthographic Projection 0 likes
A two-dimensional representation of an object on paper or other surface; the projection is at right angles to both the view and the projection lines, as in floor plans, and sections of homes
Orthotropic 2 likes
With different characteristics or strengths in mutually perpendicular symmetry planes; a particular type of anisotropy
OS&Y Valve 1 like
A valve that has external exposed threads which are held up by a yoke and which indicate whether the valve is open or closed
OSB 1 like
Oriented Strand Board
Oscillation 1 like
Moving or swinging back and forth repeatedly, from one extreme to another
Oscillograph 1 like
An instrument which records oscillations
Oscilloscope1 like
A cathode ray tube that measures an electrical signal’s changing voltage
OSHA 1 like
Occupational Safety & Health Administration
Osmosis 0 likes
The process of a solvent passing through a semi-porous layer from a dilute solution into a more concentrated solution
Ottawa Sand 0 likes
A sand which is employed as the standard to test hydraulic cements with mortar test samples; naturally round particles of almost pure quartz
Out of Phase 0 likes
When a structure moves at a different frequency from the ground motion
Out of Square 0 likes
The deviation from a genuine square
Outdoor Exposure 0 likes
Plastic pipe which is not shielded from the impact of weather such as the sun, wind, rain or snow
Outfall Sewer 0 likes
A large sewer which spans between the collection site and the disposal site
Outlet 1 like
The point into which appliances are plugged in order to draw electricity
An exit or way out
A store that sells products at a discount
Outlet Box1 like
outlet box
The receptacle which accommodates an electrical outlet and its attachments
Outline Lighting 0 likes
Positioning incandescent lamps or gaseous tubes so that they outline or highlight particular features of a building, such as its shape or door decoration
Outline Specifications 1 like
A shortened version of the specifications; usually created in design development or schematic design
Outrigger 0 likes
A rafter extension from the wall line; normally a smaller beam attached to a bigger rafter to produce a cornice or roof overhang
Outrigger Scaffold 1 like
Some scaffolding which is reinforced by outrigger beams which are cantilevered out from the structure
Outside Corner 0 likes
The place where two walls join and produce an external angle
Outside Four Inches 0 likes
The only level of stretcher courses on a wall face
Oven, Bake 0 likes
See Bake Oven
Oven, Convection4 likes
Oven Convection
See Convection Oven
Oven, Wall Mounted2 likes
oven, wall mounted
See Wall Mounted Oven
Ovendry Wood 0 likes
Wood which has been dried in a ventilated oven at 102 to 105° C; has a somewhat consistent weight
Overatomized 1 like
Scattered too finely due to overly atomized air pressure
Overcertification 0 likes
When an architect or engineer certifies more than the correct amount a contractor ought to be paid
Overcoat 1 like
Second or final coat
Overcurrent 0 likes
An electrical current that exceeds the wiring and devices’ capability
Overcurrent Device 2 likes
An apparatus that restricts a current to a preset number of amperes
Overflow 2 likes
An opening which permits rainwater overflow once it reaches a preset height, for roof drains it is usually 2 inches
Overflow System 1 like
The collection of water from the surface or a draw-off assembly
Overglaze Decoration 0 likes
Decoration made of ceramic or metal which is added and fired onto an already glazed surface of a ceramic
Overhand Work 1 like
A wall that is constructed from a scaffold positioned on only one side of the wall; the bricklayer leans over the wall to lay the brickwork on the other side
Overhang 0 likes
The part of a roof that protrudes over an external wall; See also Cornice
Overhang Beam 0 likes
A beam with one or both ends extending beyond the support; sustained by two or more supports
Overhead 1 like
Any indirect costs which are included in the total cost of sale; such costs are not directly connected to a unit of production
Overhead Concealed Closer 0 likes
A door closer that is hidden in the head frame; an arm connects to the door at the uppermost rail
Overhead Door 0 likes
A door that opens upward from the ground; frequently used in garages and warehouses
Overimprovement 1 like
An improvement to a property that is extravagant in size or cost when compared to similar properties; commonly used term when the improvement does not serve the property in the best way
Overlap 0 likes
When something is positioned in such a way that the edge is on top of and jutting out past the edge of another
Overlay 1 like
A drawing created by placing a thin piece of paper over another drawing
A thin layer of material bonded to one or both sides of a wood panel in order to provide a base for painting, either protective or decorative
Overlay Cabinet Construction 0 likes
A way to construct cabinets so that the doors and drawer fronts are positioned in front of the face frame
Overload 2 likes
Load that is larger than the amount that a particular system or machine is designed to support
Overload Protector3 likes
overload protector
Device that will prevent the operation of a unit when conditions become hazardous; operated by temperature, pressure or current; See Overcurrent Device
Oversized Brick 0 likes
A brick that has dimensions larger than 2-1/2 inches by 3-1/2 inches 7-1/2 inches
Overspray 0 likes
See Drift
Overvibration 0 likes
When freshly mixed concrete vibrates excessively when poured and causes separation
Ovolo 2 likes
A molding that is a quarter of a circle or ellipse
Owner 0 likes
A person or entity who signs the contract for a particular construction project
A person or entity with a title or interest in some portion of real property
Owner-Builder 1 like
An owner who undertakes a project and takes on the role of a general contractor
Owner-Construction Agreement 0 likes
Contract for a construction project that an owner and a contractor sign
Owner-Construction Management Agreement 2 likes
Contract for professional services that is signed by a construction manager and a client
Owners Overall Budget 2 likes
A budget that the owner creates detailing all the expenses of the project, including the purchase of land, building, financing, professional fees, and all accompanying costs
Owners Right to Stop Work 0 likes
The owner can halt work on a construction project only if the contract allows for it and only for reasons agreed to in the contract
OX, OXO, OXXO 1 like
Specifications for how sliding and fixed panels will be arranged in sliding glass doors and windows; X denotes a sliding panel; O denotes a fixed panel; See also XOOX , XO, XOO
Oxalic Acid2 likes
oxalic acid
An organic acid, toxic, typically white-colored and granular; used for breaking down iron rust stains on pool walls and floors, cleanse filter septa of iron rust, and as a bleach for wood
Oxidation 1 like
An action wherein a material chemically combines with oxygen
Oxidize 0 likes
To mix oxygen with another substance; to rust
Oxidized Sewage 0 likes
Sewage that is combined with oxygen; the process causes organic materials to stabilize
Oxidizing Flame 0 likes
A gas flame which has an oxidizing effect because it contains extra oxygen
Oxy-Acetylene 0 likes
An oxygen and acetylene mix that is employed as fuel for welding or cutting metals
Oxygen 0 likes
A gaseous element that has no color, taste odor, present in air, water, and nearly all minerals and organic matter; critical to biological life
Oxygen Cutting (OC) 1 like
Cutting processes in which metals react chemically with oxygen at elevated temperatures and are thereby severed or separated; employing a chemical flux or metal powder expedites the reaction
Oxygen-Acetylene Cutting 0 likes
A gas welding process in which a chemical reaction with oxygen and a base metal at elevated temperatures causes the metal to be cut; gas flames which result from acetylene burning with oxygen maintain the necessary temperature
Oxygen-Arc Cutting 4 likes
An oxygencutting process in which the metals react chemically with oxygen at elevated temperatures and are thereby cut; an arc positioned between an electrode and the base metal serves to maintain the required temperature
Ozone 0 likes
A type of unstable oxygen, a light blue gas that has a powerful odor and strong oxidizing characteristics; employed in deodorizing, disinfecting, bleaching, and oxidizing
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