Nail 
A metal rod used as a fastener with various materials, most often lumber. Nails come in a variety of shapes and sizes for specific uses. 

Nailer 
A piece of lumber used for the purpose of providing a surface for nailing other lumber or materials. 

Nailing Block 
A wooden block attached to or set into masonry to provide a surface for nailing other materials. 

Nail Pops 
When the structure of a new home settles, nails in the load-bearing parts tend to pop out slightly. 

Nail Puller
A bar used to remove a nail from a surface. The bar has jaws that grip the nail so it can be pried out. 

Nail Set 
A thin metal rod used to allow a nail to be driven flush with, or below, a surface without damaging the surface. 

Nail Spotter 
An applicator used to apply and smooth joint compound over the heads of fasteners on drywall. 

Naphtha 
A petroleum solvent used as a thinner for paint, lacquer, and asphalt. 

NAR (National Association of Realtors) 
Trade organization for real estate agents and brokers who become members by agreeing to abide by the organization's code of ethics. Members may call themselves Realtors. 

NAR Code of Ethics 
Formal code of ethics and standards of practice by which members of the National Association of Realtors must abide. 

Narrow U 
A staircase design with two straight runs separated by a landing and facing opposite directions. Someone using the staircase ascends to the landing, turns 180 degrees, and continues to the top. 

National Apartment Association (NAA) 
This group consists of 60 state and local associations of managers, investors, developers, owners, and builders of apartment houses and other residential rental property. Founded in 1939 and located in Washington, D.C. with 36,000 member and 11 regional groups, it has certification programs dealing with apartment management, maintenance, and property supervision. 

National Association of Corporate Real Estate Executives (NACORE) 
Founded in 1969 with 3,273 members, this group is located in West Palm Beach, Florida and consists of anyone managing, administering and/or operating regional real estate departments for national and international corporations. It provides a forum for exchange of concepts and the sharing of common interests among member. 

National Association of Exclusive Buyers Agents 
National organization of buyer's brokers whose members do not accept property listings. (800) 986-2322.

National Association of Home Builders of the U.S. (NAHB)
Founded in 1942 and located in Washington, D.C. with 155,000 members and 824 local groups, this organization of homebuilders provides educational, political information and research services. Its publications include Builder Magazine, Forecast of Housing Activity, Housing Economics, Housing Market Statistic and the Nation's Building News. Its membership consists of single, multifamily and commercial builders. 

National Association of Home Inspectors (NAHI) 
Professional association of independent home inspectors who meet the group's education and performance requirements. For a list of NAHI-certified inspectors in your area, (800) 448-3942. 

National Association of Independent Fee Appraisers (NAIFA) 
This organization of Real Estate Appraisers offers the following professional designations: IFA - Member; IFAS - Senior Member; IFAC - Appraiser-counselor. Its address is 7501 Murdoch Avenue, St. Louis, MO 63119. 

National Association of Master Appraisers 
An association that offers the Master Senior Appraiser (MSA) designation, which requires education but little or no experience. Address: 303 W. Cypress, San Antonio, Texas 78212. 

National Association of Real Estate Brokers (NAREB)
This group, founded in 1947 and located 1629 K Street N.W., Suite 602, Washington, D.C. 20006, has 7,500 members with 15 regional groups and 6 state groups. It offers certification programs for members of the real estate brokerage industry including Real Estate Management Brokers Institute, National Society of Real Estate Appraisers, Real Estate Brokerage Institute and the United Developers Council. The NAREB seeks to promote high ethical real estate practices in the real estate brokerage industry. 

National Association of Real Estate Investment Trusts (NAREIT)
A trade association that serves REITS, it collects data on the performance of REITs and prepares definitions to be used. Address: 1129 20th Street, NW, Suite 305, Washington, D.C. 20036. 

National Association of Real Estate License Law Officials (NARELLO) 
This group seeks to improve real estate licensing examination administration, improve the effectiveness of license law management and implementation, and improve real estate licensing procedures and conducts training workshops. Founded in 1930 and located 2580 South 90th Street, Omaha, NE 68124. NARELLO has 700 members consisting of state administrators managing real estate licensing laws. 

National Association of Realtors (NAR) 
Trade organization for real estate agents and brokers who become members by agreeing to abide by the organization's code of ethics. Members may call themselves Realtors. Address: 430 North Michigan Avenue, Chicago, IL 60611. 

National Association of Review Appraisers and Mortgage Underwriters 
This organization awards the Certified Review Appraiser (CRA) designation. Address: 8383 East Evans Road, Scottsdale, AZ 85260. 

National Council of Real Estate Investment Fiduciaries (NCREIF) 
Organization that collects historical data on various institutional-grade property types, sorted by geographic areas. Publishes data on income and value changes. Index, called Russell-NCREIF Real Estate Performance Report, is often cited as the benchmark for institutional real estate performance. Address: 909 A Street, Tacoma, WA 98402.

National Council of State Housing Agencies 
Nonprofit clearinghouse of information on local and state housing agencies. For information: (202) 624-7710. National Electric Code National Electric Code, which is an affiliate of the National Fire Protection Association, sets a minimum standard for electrical installations.

National Flood Insurance 
Insurance based on the National Flood Insurance Program, enacted by Congress in 1969, provides coverage for those people suffering real property losses as a result of floods. Any real estate located in a flood plain area cannot be financed through a federally regulated lender unless flood insurance is purchased. 

National Foundation for Consumer Credit
Nonprofit clearinghouse of information on nonprofit credit counseling centers nationwide. For information: (301) 589-5600.

National Real Estate Index 
Data provider for many types of property in more than 50 cities. Address: 2200 Powell Street, Suite 700, Emeryville, Ca 94608. 

National Realty Committee 
A group whose membership is primarily composed of large, high profile owners and developers. Their paramount concern is the legislative arena, especially the government's policy toward real estate finance, taxation and investment. Located at: 1420 New York Avenue, NW, Suite 1100, Washington, D.C. 20005. 

National Retail Merchants Association 
Publisher of the Department Store Lease Study, which includes data on rental rates for retail property. Address: 100 W. 31st Street, New York, New York 10001. 

National Society of Real Estate Appraisers (NSREA) 
An affiliate of the National Association of Real Estate Brokers, its purpose is to formulate rules of ethics and professional conduct and enforce these rules to the benefit of it's members. Designations given by this organization are Master Real Estate Appraiser, Certified Real Estate Appraiser and Residential Appraiser, after the completion of a course of study and final exam. 

National Tenant 
A well known and more substantial lessee with a presence in most of the United States. 

Natural Vacancy Rate
The average vacancy rate for a rental property market that would result if supply and demand were in balance. This level to which vacancy rates adjust over the long term is a benchmark by which current vacancy rates in the market are considered high or low. 

Natural Draft Cooling Tower 
A cooling tower using natural air circulation to cool water or another liquid. Used in power plants and chemical refineries. 

Natural Finish 
A finish applied to wood that provides protection without masking the natural grain and color. 

Natural Gas 
A naturally occurring gas used as a fuel in furnaces and power plants. Natural gas is commonly found in oil-producing areas. 

Natural Resin 
Organic fluid used to make paint and varnish. 

Natural Ventilation 
Circulation of air without the assistance of a fan or other mechanical device. Naturalization Act of receiving the rights and privileges of a citizen including property rights. 

NCREIF 
National Council of Real Estate Investment Fiduciaries.