Term Definition
NIBS 1 like
National Institute of Building Sciences
NIC 2 likes
Not in Contract
Niche 0 likes
A small concave cavity in a wall surface or panel, serving as a decorative element; also used for storing objects
Nickel 0 likes
A metallic element, number 28 on the Periodic Table; characterized by its ductility, malleability, silver-white color and corrosion resistance
Nickel Silver 1 like
A metallic composite compound uniting 60% copper, 20% nickel and 20% zinc, known for its hardness and corrosion resistance; does not contain real silver
Nickel Steel 0 likes
A steel compound that consists mainly of nickel
Night Depository 0 likes
An opening in a building’s outside wall to enable the supply of materials to a business when it has closed for the day’s transactions
NIMBY 0 likes
Acronym for Not in My Back Yard; describes an owner’s opposition to a proposal to launch a valuable development such as a school, too close to the owner’s property
Nineteen-Inch Selvage 0 likes
A roofing sheet with 17 inch granule surface and a selvage edge that has a 19 inch non-granule-surface; Nineteen-inch selvage is also called a Split Sheet
Nipple1 like
Small pipe that has male threads on each end
Nipple, Bushed 2 likes
See Bushed Nipple
Nipple, Offset4 likes
nipple, offset
See Offset Nipple
NIST 0 likes
National Institute of Standards & Technology
Nitrocellulose 0 likes
Compound employed widely in producing plastics and lacquers; produced when cellulose is treated with chemicals; see Cellulose Nitrate
Nitrogen Dioxide 0 likes
Slightly toxic gas (NO2) in smog and car exhaust fumes
NLGA 1 like
The National Lumber Grades Authority
No-Fines Concrete 1 like
A coarse concrete mixture
No-Frost Freezer2 likes
no-frost freezer
A low-temperature refrigerator compartment that does not collect frost or ice on freezer surfaces or its contents
No-Hub Pipe2 likes
no-hub pipe
Cast iron pipe manufactured without hubs and fastened with stainless steel and rubber
Noble Gas 0 likes
Gaseous element that very rarely combines with other elements, such as helium, neon, argon, krypton and radon; also called Inert Gas or Rare Gas
NOFMA 1 like
National Oak Flooring Manufacturers Association
Nogging 4 likes
Filling brick between roof rafters to making the building windproof
Noil 0 likes
Short wool fibers that are separated from the long fibers by combing; a by-product in worsted yarn production
Noise 2 likes
An unwanted sound that irritates hearing
Noise Reduction 1 like
Reducing the level of sound pressure by altering sound from a source or signal; can be achieved by installing an intervening wall
Noise Reduction Coefficient (NRC) 0 likes
Numerical rating on a scale from 0 to 1 to express how much sound a material absorbs
Nomenclature 1 like
A system of names used for items in a specific science or art.
Nominal Dimension 1 like
Size expressed in numbers as opposed to the real size; an approximation of the dimensions assigned to goods and materials as a convenience
Nominal Size 0 likes
The named size; the nominal size of a wood stud is 2 inches by 4 inches which is larger than the actual size
Nomogram 1 like
A graph with three or more lines adjusted to scale and arranged so that a straight line intersects with any two lines at their acknowledged values, and intersects with the third line at the value of the related variable
Non-Agitating Unit 0 likes
A truck unit that transports ready-mixed concrete over short distances; does not provide agitation
Non-Automatic 3 likes
Action by personal or manual intervention is necessary
Non-Code Installation 0 likes
System or unit installation where there are no enforced local, state, or national codes
Non-Destructive Testing 1 like
Testing of building materials so that the quality of the materials are not compromised
Non-Drying Oils 0 likes
Oils that don’t absorb oxygen from the air or change from a liquid to a solid, such as mineral oils
Non-Evaporable Water 1 like
Water in concrete which is a permanent part of the concrete as a result of the chemically combination during cement hydration
Non-Ferrous Metal 0 likes
A metal that has no iron
Non-Grain-Raising Stain 0 likes
Wood stain that does not elevate wood grain; produced by dissolving dyes in a special solvent; also called NGR Stain
Non-Load Bearing Partition 2 likes
An unnecessary interior wall used to create compartments in a room
Non-Metallic Tubing3 likes
non-metallic tubing
A round cross-section sheath tube manufactured from a moisture-resistant, flame-inhibiting materials
Non-Pressure Drainage 1 like
Where downward sloping pipes in drainage are not full
Non-Rising Pin 4 likes
See Fast Pin Hinge
Non-Shrink Grout3 likes
non-shrink grout
Cement or epoxy based mix that fills the gap between bearing parts that does not diminish in size over time
Non-Shrink Grout, Nonmetallic 0 likes
Grout that contains no metallic substances and will not diminish in size over time
Non-Slip Terrazzo3 likes
non-slip terrazzo
Portland cement and marble chip mixture on Portland cement and sand; coarsened with iron fillings, carborundum powder or dented while moist
Non-Slip Tile3 likes
non-slip tile
Tile having non-slip properties due to an abrasive mixture, abrasive particles, grooves or patterns in the surface, or may be due to a naturally occurring non-skid surface
Non-Volatile 0 likes
When a substance that does not evaporate at normal temperatures
Nonaxial 0 likes
At an angle to the long axis of a structural element
Nonbearing 0 likes
Something that does not support a load
Nonbearing Partition2 likes
nonbearing partition
A divider that spans from floor to ceiling but does not support loads; only supports its own weight
Nonbearing Wall 0 likes
A wall that only supports its own weight
Noncombustible 1 like
Any material that does not catch fire or facilitate combustion in air up to 1200° F when subjected to fire
Noncondensable Gas 2 likes
Gas that does not transform into a liquid
Nonconforming Use 1 like
Land use that does not comply with the zoning code; applies primarily to land that was used for other purposes prior to the new zoning approval; the non-conforming use may continue as long as there is no interruption
Nonflammable 0 likes
Does not burn; incombustible
Nonfrosting Evaporator 0 likes
Evaporator that doesn’t gather frost on its surface
Nonrecourse Mortgage 0 likes
In this situation, the borrower is not personally liable and the lenders only solution is to foreclose the property when the borrower defaults on payment obligations
Nontoxic 1 like
No poison involved
Nonvitreous 1 like
Non-vitrified; unable to be changed into glass
Norm 1 like
A standard or model that is considered normal in society; a customary situation
Normal Charge 1 like
Partially gaseous and partially liquid thermal element charge in all functioning circumstances
Normal Consistency 3 likes
Milliliters of water per 100 grams of plaster or concrete comprising gypsum to yield a mortar of specific fluidity
Normal Fault 1 like
As a result of tension, a block descends to the dip or through the slope of a fault plane
A defect that detracts from the functioning or perfection of something
Normal Weight Concrete 0 likes
Tough, high density concrete made from the same or similar density of aggregate
Norman Brick 1 like
A 2-3/4 inch by 4 inch by 12 inch brick
North American Insulation Manufacturers Association 1 like
44 Canal Center Plaza, #310, Alexandria, Virginia 22314, Tel: (703) 684-0084, Fax: (703) 684-0427, URL: www.naima.org/
North Pole 1 like
Most northern point of the axis of rotation of the earth
Magnet pole pointing north
Northeastern Lumber Manufacturers Association 0 likes
4 Fundy Road, Falmouth, Maine 04105, Tel: (207) 829-6901, Fax: (207) 829-4293, URL: www.nelma.org/
Nosing 1 like
Protruding edge of an architectural molding or drip or the rounded edge of a stair tread that projects horizontally
Nosing, Rubber 1 like
See Rubber Nosing
Not in Contract (NIC) 1 like
Displayed on contract drawings to reference, but not part of the construction contract
Notary Public 1 like
A person who is legally authorized to certify the authenticity of documents and signatures; a notary
Notch 0 likes
A v-shaped cut or groove on the surface of a member
Notched Trowel1 like
notched trowel
A tile setters trowel with jagged edges that disperses bonding substances controlled by the teeth size and their spacing; also used in preparing durable flooring
Note 0 likes
Document describing the amount of debt and payment terms
Note Payable 1 like
Amount owed due to a promissory note provided to a creditor
Note Receivable 0 likes
Promissory note provided by a customer to pay a specific amount of money to a business within a definite time frame
Notice 0 likes
Information delivered to someone
Notice of Cessation 1 like
Written notice filed by an owner or their agent stating that there has been an absence of labor for a specific time, and defining the time left to exercise lien rights by those involved
Notice of Completion 0 likes
A written notification filed by an owner or their agent stating that a project is complete, and defining the time left to exercise lien rights by those involved
Notice of Non-responsibility 1 like
When correctly recorded and displayed on the premises, this notice releases the owner from mechanic’s liens that have been placed on the property for work and materials ordered by lessees
Notice to Pay Rent or Quit 1 like
This document, which is required before a tenant is evicted, is a legal notice that is delivered to a tenant who has defaulted on rental payments
Notice to Proceed (NTP) 0 likes
This document is a written notice advising a contractor to continue with work under the terms of a contract
Novation 1 like
Substituting a new legal responsibility for a previous one
Nozzle3 likes
A component of a heating system that sprays fuel into a combustion chamber
NPA 0 likes
National Particleboard Association
NPVLA 2 likes
National Paint & Coatings Association
NRC 0 likes
Noise Reduction Coefficient
NRCA 0 likes
National Roofing Contractors Association
NRMCA 1 like
National Ready Mixed Concrete Association
NRP 0 likes
Non-Rising Pin
NSF 0 likes
National Sanitation Foundation
NSPI 2 likes
National Spa & Pool Institute
NTIS 0 likes
National Technical Information Service
NTMA 1 like
National Terrazzo and Mosaic Association
NTP 1 like
Notice to Proceed
NTS 1 like
Not to Scale
Nuclear Meter 0 likes
A device that discovers and measures moisture
Nurse Station Indicator 0 likes
A device at a nurse’s station that patients turn on when they need nursing assistance
Nursing Care Facility 0 likes
An institution that provides nursing care services to people needing constant care and attention 24 hours a day
Nut1 like
A small square or six-sided piece of flat material with a hole that enables the end of a bolt to connect and attach to keep it in place
Nut, Hex2 likes
nut hex
See Hex Nut
NW 0 likes
No Weather; See Grade NW Brick
NWMA 2 likes
National Woodwork Manufacturers Association
NWWDA 2 likes
National Wood Window & Door Association
Nylon 0 likes
A tough synthetic material used for textiles, food containers and industrial purposes
Nylon Carpet1 like
nylon carpet
A carpet manufactured from synthetic nylon fibers
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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