326 Appendix 2
Mansard A four-sided, steep-sloped roof.
Masonry Opening The actual distance between masonry units where an opening occurs. It does
not include the wood or steel framing around the opening.
Masonry Veneer A layer of masonry units that are bonded to a frame or masonry wall.
Master Specification A resource specification section containing options for selection, usually cre-
ated by a design professional firm, which once edited for a specific project becomes a contract specification.
Master Format Industry standard for organizing specifications and other construction information,
published by CSI and Construction Specifications Canada. Formerly a 5-digit number system with 16 divi-
sions. Now a 6- or 8-digit numbering system with 49 divisions.
Masterspec® Subscription master guide specification library published by ARCOM and owned by
the American Institute of Architects. http://www.specguy.com/www.masterspec.com
Mastic An adhesive used to hold tiles in place; also refers to adhesives used to glue many types of
materials in the building process.
Mechanical Drawing Applies to scale drawings of mechanical objects.
Mechanics’ Lien A lien on real property created by statute in all states in favor of person supplying
labor or materials for a building or structure for the value of labor or materials supplied by them. In some
jurisdictions a mechanic’s lien also exists for the value of professional services. Clear title to the property
cannot be obtained until the claim for the labor, materials or professional services is settled.
Mesh A metal reinforcing material placed in concrete slabs and masonry walls to help resist
cracking.
Metal Wall Ties Corrugated metal strips used to bond brick veneer to its support wall.
Mezzanine or Mezzanine Floor That portion of a story which is an intermediate floor level placed
within the story and having occupiable space above and below its floor.
Modules A system based on a single unit of measure.
Modulus of Elasticity (E) The degree of stiffness of a beam.
Moisture Barrier Typically a plastic material used to restrict moisture vapor from penetrating into
a structure.
Moldings Trim mounted around windows, floors, and doors as well as closets.
Monolithic One-Pour System A method of poured-in-place concrete construction that is without
joints.
Mortar The mixture of cement, sand, lime, and water that provides a bond for the joining of masonry
units.
Multifamily Dwelling Any building consisting of more than two dwelling units.
Nailer A wood member bolted to concrete or steel members to provide a nailing surface for attach-
ing other wood members.
Negligence Failure to exercise due care under the circumstances. Legal liability for the conse-
quences of an act or omission frequently depends upon whether or not there has been negligence. See
also Due Care.
Net Size The actual size of an object.
Newel The end post of a stair railing.
Nominal Size The call-out-size. May not be the actual size of the item.
Nonbearing Wall A wall that supports no loads other than it own weight. Some building codes con-
sider walls that support only ceiling loads as nonbearing.
Nonconforming Work Work that does not fulfill the requirements of the contract documents.