Term Definition
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 Toilet4 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 2 likes
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 2 likes
A glaze that is not transparent, with or without color
Open Bid/Estimate 3 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 1 like
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 2 likes
Rock or other naturally occurring solid mineral that contains extractable quantities of metals or minerals of commercial value
Organic 1 like
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 5 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 1 like
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
Product of the day

How to Fix Plumbing Noises In Your Home

plumbing fiberglass insulationTo diagnose loud plumbing, you must first determine whether the unwanted sounds occur on the system's inlet side - in other words, when water is turned on - or on the drain side. Noises on the inlet side have various causes: excessive water pressure, worn valve and faucet parts, poorly connected pumps or other appliances, incorrectly placed pipe fasteners, and plumbing runs with excessive tight bends or other restrictions. Noises on the drain side usually originate from poor location or, as with some inlet side noise, a layout with tight bends.


Hissing that occurs when a faucet is opened slightly generally signals excessive water pressure. Consult your local water company if you suspect this problem. They will tell you about the water pressure in your area and if necessary, can install a pressure reducing valve on the incoming water supply pipe.


Thudding, often accompanied by shuddering pipes when a faucet or appliance valve is turned off, is a condition called water hammer. The noise and vibration are caused by the reverberating wave of pressure in the water, which suddenly has no place to go. Sometimes opening a valve that discharges water quickly into a section of piping with a restriction, elbow, or tee fitting can produce the same condition. Water hammer can usually be fixed by installing fittings called air chambers or shock absorbers in the plumbing to which the problem valves or faucets are connected. These devices permit the shock wave produced by the halted flow of water to dissipate in the air, which unlike water, is compressible. Older plumbing systems may have short vertical sections of capped pipe behind walls on faucet runs for the same purpose; these can eventually fill with water, reducing or destroying their effectiveness. The solution is to drain the water system by turning off the main water supply valve and opening all faucets. Then open the main supply valve and close the faucets one at a time, starting with the faucet closest to the valve and ending with the one furthest away.

Chattering or Screeching

Intense chattering or screeching that occurs when a valve or faucet is turned on, and that usually disappears when the fitting is fully open, signals loose or defective internal parts. The solution is to replace the valve or faucet with a new one. Pumps and appliances such as washing machines and dishwashers can transfer motor noise to pipes if they are improperly connected. Link these items to plumbing with plastic or rubber hoses - never rigid pipe - to separate them.

Other Inlet Side Noises

Creaking, squeaking, scratching, snapping, and tapping are usually caused by the expansion or contraction of pipes, generally copper ones supplying hot water. The sounds occur as the pipes slide against loose fasteners or strike nearby house framing. You can often pinpoint the location of the problem if the pipes are exposed; just follow the sound when the pipes are making noise. Most likely, you will discover a loose pipe hanger or an area where pipes lie so close to floor joists or other framing pieces that they clatter against them. Attaching foam pipe insulation around the pipes at the point of contact should resolve the problem. Be sure straps and hangers are secure and provide sufficient support. Where possible, pipe fasteners should be connected to large structural elements such as foundation walls instead of framing; doing this reduces the transmission of vibrations from plumbing to surfaces that can amplify and transfer them. If attaching fasteners to framing is unavoidable, wrap pipes with insulation or other resilient material where they contact fasteners, and sandwich the ends of new fasteners between rubber washers when installing them. Correcting plumbing runs that suffer from flow-restricting tight or numerous bends is a last resort that should be performed only after consulting a skilled plumbing contractor. Unfortunately, this situation is common in older homes that may not have been built with indoor plumbing or that have been through several remodels, particularly by unprofessional contractors.

Drainpipe Noise

On the drain side of plumbing, the main goals are to eradicate surfaces that can be struck by falling or rushing water and to insulate pipes to contain unavoidable sounds. In new construction, bathtubs, shower stalls, toilets, and wall-mounted sinks and basins should be set on or against resilient under-layments to lower the transmission of sound through them. Water-saving toilets and faucets are less noisy than conventional models; install them instead of older types even if codes in your area still allow older fixtures. Drainpipes that do not run vertically to the basement or that branch into horizontal pipe runs supported at floor joists or other framing present especially troubling noise problems. These pipes are large enough to radiate substantial vibration; they also carry significant amounts of water, which makes the situation worse. In new construction, use cast-iron soil pipes (the large pipes that drain toilets) if you can afford them. Their immense size contains much of the noise made by water traversing them. Also, avoid routing drainpipes in walls shared with bedrooms and rooms where people gather. Walls containing drainpipes should be soundproofed as stated earlier, using double panels of sound-insulating fiberboard and wallboard. Pipes can be wrapped with special fiberglass insulation made for the purpose; these pipes have an impervious vinyl skin that sometimes containing lead. Results are not always acceptable.

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