nailer:A piece of lumber secured to non-nailable decks and walls by bolts or other means, providing a suitable backing onto which roof components may be mechanically fastened.
natural finish:A transparent finish that does not significantly alter the original color or grain of the natural wood. A natural finish is typically achieved using sealers, oils, varnishes, water-repellent preservatives, and other similar materials.
neat plaster:A base coat plaster that does not contain aggregates and is used where the addition of aggregates on the job is desired.
NEC (National Electrical Code):A set of rules governing safe wiring methods. Local codes that are backed by law may differ from some codes in the NEC.
neoprene:A synthetic rubber having physical properties that closely resemble those of natural rubber, and used in weather-resistant products, such as paints, adhesives, gaskets, etc. It is made by polymerizing chloroprenes, which are produced from acetylene and hydrogen chloride.
nesting:A method of re-roofing with new asphalt shingles over old shingles in which the top edge of the new shingles is butted against the bottom edge of the existing shingle tab.
neutral wire:Carries electricity from an outlet back to the service panel; usually color-coded white. See also hot wire and ground.
newel:Any post to which the end of a stair railing or balustrade is fastened.
NFPA:National Fire Protection Association, which sets standards for fire-rated building products.
nipple:A short pipe coupling that is threaded on both ends and installed between fittings.
NM (non-metallic):A flame-retardant type of Romex cable, which is a non-metallic sheathed cable that contains several conductors. Its use is limited to dry locations.
NMC (non-metallic conduit):A type of Romex® cable, which is a non-metallic sheathed cable that contains several conductors. NMC may be used in damp or corrosive locations, as well as dry areas.
no-cutout shingles:Shingles consisting of a single solid tab with no cutouts.
nominal size:Size used for identification only; not literal dimensions.
non-bearing wall:A wall supporting no load other than its own weight.
non-combustible:A substance that does not burn when subjected to fire.
non-destructive:Describes a method of examining the interior of a component whereby no damage is done to the component itself.
non-drying:A sealant that does not set up or cure. See also butyl. Also called non-curing.
non-fibered aluminum roof coating:Thin but efficient barrier that reflects the sun's harmful rays and prolongs a roof surface's service life. Also used on other metal surfaces.
non-fibered roof and foundation coating:Dual-purpose, thin-viscosity material that doubles as a non-fibered roof and foundation coating.
non-sag:A sealant formulation having a consistency that permits application in vertical joints without appreciable sagging or slumping.
non-skinning:Descriptive of a product that does not form a surface skin.
non-staining:Characteristic of a compound that will not stain a surface.
non-veneer panel:Any wood-based panel that does not contain veneer and carries an APA span rating, such as waferboard and oriented strand board.
normal operating controls:The operating controls for devices that can be operated by ordinary occupants, such as thermostats, as they require no specialized skill, knowledge or tools.
normal slope application:Method of installing asphalt shingles on roof slopes between 4 inches and 21 inches per foot.
nosing:The projecting edge of a molding or drip usually applied to the projecting molding on the edge of a stair tread.
notch:A crosswise rabbet at the end of a board.
note:A formal document showing the existence of a debt and stating the terms of repayment.
nozzle:The tubular tip of a caulking gun through which the compound is extruded.
nuclear meter:A device used to detect moisture by measuring slowed, deflected neutrons.