Term Definition
U Stirrup 2 likes
A U-shaped steel loop bar employed as fortification against the diagonal tension in a member
U-Value 3 likes
See Coefficient of Heat Transmission
U.S. Department of Justice (DOJ) 2 likes
10th & Constitution Avenue, NW, Washington, DC 20530, Tel: (202) 514-2000; URL: http://www.justice.gov/
UF Cable 0 likes
Underground Feeder Cable
UHF Cable3 likes
UHF cable
Cable employed for ultra-high frequency
Ultimate Compressive Strength 6 likes
The stress when a material is in a state of crushing
Ultimate Load 2 likes
The maximum magnitude of load that a structure can sustain, only restricted by total failure
Ultimate Strength 1 like
Maximum strength in a material
Ultramicroscopic 1 like
Too small to be viewed with a normal microscope
Ultrasonic Transmitter2 likes
ultrasonic transmitter
Apparatus that converts sounds vibrations into equivalent wave forms above human hearing range
Ultraviolet 1 like
Invisible rays of the spectrum on the violet end
Invisible radiation waves with frequencies shorter than visible light and longer than X-ray wavelengths
Unadulterated 1 like
Unbalanced Wall 4 likes
See Unsymmetrical
Unbalancing the Schedule of Values 1 like
See Front end loading
Unbonded Construction 0 likes
Construction contract where a surety bond has not been submitted by the contractor
Uncertainty 2 likes
The doctrine that contracts cannot be enforced if they are incomprehensible
Unctuous 1 like
Oily, greasy, or soapy feel; pertaining to minerals
Uncut loop 4 likes
Carpet pile yarns that continue from tuft to tuft with observable loops
Underbid 2 likes
Bidding less than a competitor
Undercapitalized 2 likes
Not having enough capital to function efficiently and effectively
Undercoat 0 likes
A layer or layers of paint applied before the finishing coats; sometimes called the Prime coat(s)
Undercut 2 likes
A groove at the base metal next to weld toe without weld metal
Underdrain 1 like
Punctured pipe drain mounted in crushed stone beneath a slab to collect ground water and redirect it away from the structure or building
Underestimate 2 likes
To make an estimate of something that is too low
Underfloor Duct 3 likes
A circular or rectangular metal pipe positioned under a wood or concrete floor to transfer warm air from a heating or air conditioning system
Underground 1 like
Underground Feeder Cable2 likes
underground feeder cable
Insulated electrical cable appropriate for subterranean use
Underground Paper 7 likes
Wallpaper that does not have a background color
Underground Plumbing 1 like
Plumbing drain and waste lines below a basement floor
Underground Tank 0 likes
A storage container that is located underground
Underlay2 likes
One or more layers of felt that serve as a base sheet on which finish roofing is employed
See Carpet Padding
Underlayment 2 likes
A ¼ inch material positioned over the subfloor and under finish coverings in order to provide a smooth surface
A secondary waterproof or water-resistant roofing layer on the roof deck below shingles or another roof-finishing layer
Underpinning 0 likes
Installing new foundations below an existing structure
Underslab Drainage 1 like
Continually capturing and removing ground water from under a concrete slab by means of a perforated pipe
Underwater Light2 likes
underwater light
A light fitting designed to light up a pool from under the water surface
Underwriter’s Laboratories Label (ULL) 3 likes
A label on a manufactured item indicating compliance with the minimum standards of the Underwriter’s Laboratories requirements for safety and quality
Underwriters Laboratories (UL) 2 likes
An organization that classifies roofs for fire properties and wind resistance for the benefit of insurance companies in the United States
Underwriters Laboratories of Canada (ULC) 4 likes
7 Crouse Road, Scarborough, Ontario, Canada M1R 3A9, Tel: (416) 757-3611, URL: www.ul.com/canada/eng/pages/
Underwriters Laboratories, Inc (UL) 4 likes
333 Pfingsten Road, Northbrook, Illinois 60062, Tel: (708) 272-8800 URL: www.ul.com
Undivided Interest 2 likes
Joint ownership of an interest in the entire property rather than in a distinct part thereof
Unemployment Tax 1 like
A program employers fund on a quarterly basis to the Unemployment Insurance Fund; benefits are paid to qualified ex-employees according to their wages
Unencumbered Property 0 likes
Real property that is free and clear, with no impediments
Unfaced Insulation4 likes
unfaced insulation
Insulation that lacks a vapor barrier
Unfinished Bolt1 like
 unfinished bolt
A standard carbon steel bolt
Unforeseen Conditions 1 like
Unexpected situations or conditions that could impact the contract
Ungrounded Cable 2 likes
Two-wire covered cable that has one neutral wire and one hot wire
Uniform Building Code (UBC) 3 likes
A model building code by the International Building Officials Conference; employed by numerous cities and counties
Uniform Commercial Code (UCC) 4 likes
A statute governing commercial transactions that has been adopted throughout the United States
Uniform Sand 2 likes
A sand mixture where the majority of the granules are approximately the same size
Union 0 likes
A plumbing fitting that fastens one end of a pipe to another without having to turn either pipe
Union T 1 like
A pipe tee with a fitting on one end that fastens two pipes without turning them
Unit and Mullion System 2 likes
A curtain wall assembly made of prefabricated panel units fastened with mullions onsite
Unit Cost 0 likes
Cost per unit; or cost per unit of length, volume or area
Unit Heater3 likes
unit heater
An instrument for heating an area that does not require ducts
Unit Masonry 1 like
Fabricated or natural construction units, including concrete, glass, stone and gypsum
Unit Price 2 likes
Fee charged for a single unit or minimum quantity of work to be performed, including all associated materials, equipment, or services
Unit Price Contract 3 likes
A written agreement where the owner agrees to pay the contractor a specific amount of money for each unit of work properly accomplished
Unit Stress 2 likes
The force exerted on a component divided by its cross-sectional area, expressed in pounds per square inch in imperial units
Unit Vent 1 like
A vent pipe that is associated with at least two traps
Unit Ventilator2 likes
unit ventilator
A fan coil unit with an aperture through an outside wall for the passage of air
Unit Weight 2 likes
The weight of a unit volume of a material; also density
Unitary Package Unit 4 likes
A conditioning air system in an outdoor assembly resembling a rooftop unit, although the supply and return ducts are located horizontally through an exterior wall
Unitary System 0 likes
A heating/cooling system for conditioning one room or area
United States Customary Systems 1 like
Measuring units employed in the U.S., known as Imperial Units, such the pound inch, foot, mile, gallon, and second
Universal Motor1 like
universal motor
Electric motor that functions with a-c or d-c
Unjust Enrichment 0 likes
A situation where a party gains unfair advantage at the expense of another party
Unlawful Detainer Action 0 likes
Lawsuit for the purpose of evicting a defaulting tenant from a property
Unlined Stack 1 like
A chimney constructed solely of brick; may have a cement plaster lining, but no terra cotta flue lining
Unplasticized Polyvinyl Chloride2 likes
(uPVC); an inflexible plastic substance from which many construction components are fabricated, including windows, doors, and corrugated roofs
Unrated Door4 likes
unrated door
A door which has not been graded for fire resistance
Unreasonable Hardship 1 like
Situation where an enforcing agency determines that adhering to their building standard causes the specific work in a project to be unfeasible; determination is based on comprehensive evaluation of all pertinent factors
Unreinforced 2 likes
Concrete components built without steel fortified bars or welded wire
Unstable 2 likes
A structure that is not firm, fixed or solid; collapsible
Upset Price 1 like
A guaranteed top price in an agreement
Upside Down Roof 2 likes
A membrane roof where thermal insulation sits on top of the membrane
uPVC5 likes
Unplasticized Polyvinyl Chloride
Urban Renewal 0 likes
The revival of an inner city area that has deteriorated
Urethane Board 0 likes
Inflexible type of plastic foam
Urethane Foam2 likes
urethane foam
Foam insulation between a container’s interior and exterior walls
Urethane Padding1 like
urethane foam
Plastic foam of polyurethane employed to cushion carpeting
Urethane Roof 1 like
A roof that has plastic foam of rigid polyurethane; in board form or sprayed onto the roof
Urethane, Rigid 1 like
Sheet or board plastic foam of inflexible polyurethane
Urinal2 likes
A plumbing receptacle attached to a wall into which men urinate
Urinal Carrier 0 likes
A metal structure mounted on a bathroom wall to hold and brace a urinal
Urinal Screen4 likes
urinal screen
A privacy partition that isolates urinals, installed on the floor, ceiling or wall
Urn, Coffee3 likes
urn, coffee
See Coffee Urn
USC 2 likes
United States Code
USC&GS 3 likes
United States Coast and Geodetic Survey
USCS 3 likes
United States Customary Systems
USDA 1 like
United States Department of Agriculture
Useful Life 4 likes
The anticipated time period a coating is expected to be beneficial
USGS 1 like
United States Geological Survey
USS 1 like
United States Standard
Usury 2 likes
Charging a greater fee than the permissible legal maximum interest rate
Utensil Washer, Medical 0 likes
See Medical Utensil Washer
Utility 3 likes
A public utility service such as electricity or water
Utility Easement 0 likes
Location of earth that contains gas, electric, or telephone lines, possibly in the locale of a homeowner; the utility company has the legal right to maintain or repair the line at this location
Utility Excavation 3 likes
Mining existing cable buried in the ground, or creating a trench to place new cable
Utility Knife3 likes
utility knife
A widely employed knife with a handle and razor-type blade
See Board Knife
Utility Pole 1 like
An upright pole with transverse arms that supports electrical and telephone lines
Utility Room 2 likes
A room, such as a laundry, that accommodates domestic appliances
UV 2 likes
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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