U-Bolt
A bolt shaped like the letter "U," with threading on both straight sections.

UCC
see Uniform Commercial Code.

UF Wire
Plastic insulated cable used for underground wiring.

U-Hanger
A metal fastener used to attach pipes to wooden joists under a floor.

Ullage
The empty portion of a partially filled tank.

Ultimate Strength
A maximum force an object can tolerate before failure.

Ultra Vires
Action that is beyond what is legally allowed.

Ultrasonic
Vibrations above the range of normal human hearing (50kHz or higher).

Ultrasonic Examination
An inspection method using ultrasonic waves to locate structural flaws in a sample of material.

Ultrasonic Stud Finder
A device using ultrasonic waves to detect studs behind a wall.

Ultraviolet
Light that is above the visible spectrum.

Undercoat
A priming coat of paint.

Undercounter Lavatory
see Lavatory, Under Counter.

Underdrain
A drainage system installed under a slab or street to divert and channel away excess water.

Underfloor Raceway
Hollow metal sections installed under a floor to contain electrical wiring. See also Underfloor Wiring System.

Underfloor Wiring System
Wires, for example electrical, which are placed beneath the flooring of a structure.

Underground Feeder Cable
Electrical cable with moisture resistant insulation, designed for underground use.

Underground Service
Electrical power lines that are run underground in the street and to the building. Underground service has largely replaced the use of above-ground power lines in new housing developments.

Underimprovement
Property improvements that are below the usual standard expectations.

Underlayment
Layer of wood between the floor and the subfloor.

Underlying Mortgage
The first mortgage on a property when other mortgages exist on the same property.

Underpinning
Reinforcement of a building with supports or the use of beams temporarily while the structure is being built.

Undersupply
When demand exceeds the amount of real estate property available causing the prices to rise.

Undertone
A light paint color.

Underwriter's Laboratories (UL)
Independent testing group that assesses the safety and quality of various electrical components. Once a product is approved, the manufacturer can place a "UL" label on the item.

Underwriting
Lenders evaluation of the risks posed by a borrower so that they can then set conditions for the loan.

Underwriting Fee
Fee charged by the lender to do the work to verify information, necessary to make a decision as to whether or not to approve a loan.

Undisclosed Heir
One who claims, after the death of an owner lacking a will, a right to a piece of that property.

Undisclosed Principal
When a major party to a transaction remains anonymous or when one party is not informed that there is a principal.

Undisclosed Spouse
A marital partner, who is not mentioned in a will but can claim a right to a piece of property.

Undivided Interest
Ownership by two or more persons, which entitles each to the right to use the entire property.

Undue Influence
When a person is forced to perform in a certain manner due to excessive influence, pressure or fear brought by another party and may be used to void a contract.

Unearned Income
Income received for work not yet finished, such as payment in advance for contracting work.

Unearned Increment
An increase in the value of a property, which is not due to any effort on the part of the owner.

Unemployment
Nonavailability of jobs for people able and willing to work.

Unemployment Insurance
State run insurance program, funded by employers and payroll taxes, that provides workers with weekly payments when they are fired or laid off.

Unencumbered
Real estate that is fear and clear of liens and obligations, such as a house without a mortgage.

Unenforceable
Contract that is not able to be legally enforced by the courts, such as contracts with minors and those containing fraud.