Mantel- The shelf above a fireplace opening. Also used in referring to the decorative trim around a fireplace opening.

Manufactured wood- A wood product such as a truss, beam, gluelam, microlam or joist which is manufactured out of smaller wood pieces and glued or mechanically fastened to form a larger piece. Often used to create a stronger member which may use less wood. See also Oriented Strand Board.

Manufacturer's specifications- The written installation and/or maintenance instructions which are developed by the manufacturer of a product and which may have to be followed in order to maintain the product warrantee.

Masonry- Stone, brick, concrete, hollow-tile, concrete block, or other similar building units or materials. Normally bonded together with mortar to form a wall.

Mastic- A pasty material used as a cement (as for setting tile) or a protective coating (as for thermal insulation or waterproofing)

Mechanics lien- A lien on real property, created by statue in many years, in favor of persons supplying labor or materials for a building or structure, for the value of labor or materials supplied by them. In some jurisdictions, a mechanics 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. Timely filing is essential to support the encumbrance, and prescribed filing dates vary by jurisdiction.

Metal lath- Sheets of metal that are slit to form openings within the lath. Used as a plaster base for walls and ceilings and as reinforcing over other forms of plaster base.

Microlam- A manufactured structural wood beam. It is constructed of pressure and adhesive bonded wood strands of wood. They have a higher strength rating than solid sawn lumber. Normally comes in l ½" thickness' and 9 ½", 11 ½" and 14" widths

Milar (mylar)- Plastic, transparent copies of a blueprint.

Millwork- Generally all building materials made of finished wood and manufactured in millwork plants. Includes all doors, window and door frames, blinds, mantels, panelwork, stairway components (ballusters, rail, etc.), moldings, and interior trim. Does not include flooring, ceiling, or siding.

Miter joint- The joint of two pieces at an angle that bisects the joining angle. For example, the miter joint at the side and head casing at a door opening is made at a 45° angle.

Molding- A wood strip having an engraved, decorative surface.

Monopost- Adjustable metal column used to support a beam or bearing point. Normally 11 gauge or Schedule 40 metal, and determined by the structural engineer

Mortar- A mixture of cement (or lime) with sand and water used in masonry work.

Mortgage- Loan secured by land.

Mortgage broker - A broker who represents numerous lenders and helps consumers find affordable mortgages; the broker charges a fee only if the consumer finds a loan.

Mortgage company - A company that borrows money from a bank, lends it to consumers to buy homes, then sells the loans to investors.

Mortgage deed- Legal document establishing a loan on property.

Mortgagee- The lender who makes the mortgage loan.

Mortgage loan- A contract in which the borrower's property is pledged as collateral. It is repaid in installments. The mortgagor (buyer) promises to repay principal and interest, keep the home insured, pay all taxes and keep the property in good condition.

Mortgage Origination Fee- A charge for work involved in preparing and servicing a mortgage application (usually one percent of the loan amount).

Mortise- A slot cut into a board, plank, or timber, usually edgewise, to receive the tenon (or tongue) of another board, plank, or timber to form a joint.

Mudsill- Bottom horizontal member of an exterior wall frame which rests on top a foundation, sometimes called sill plate. Also sole plate, bottom member of interior wall frame.

Mullion- A vertical divider in the frame between windows, doors, or other openings.

Muntin- A small member which divides the glass or openings of sash or doors.

Muriatic acid- Commonly used as a brick cleaner after masonry work is completed.

Mushroom- The unacceptable occurrence when the top of a caisson concrete pier spreads out and hardens to become wider than the foundation wall thickness.