Masonry Glossary
Want to learn more about the materials and accessories that make masonry wall systems work? Search our glossary of essential terms for a primer on the components of well-built masonry walls.
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
A
Abutment
The supporting wall or pier that receives the thrust of an arch.
Aggregate
Granular material consisting of normal weight or lightweight particles used with a cementing medium to form concrete masonry, mortar or grout.
American Institute of Architects (AIA)
The American Institute of Architects is the voice of the architecture profession dedicated to serving its members, advancing their value and improving the quality of the built environment.
American Society for Testing and Material (AS
A global forum for the development of consensus standards.
American Society of Civil Engineers (ASCE)
A society working to represent civil engineers and provide quality information and resources on technical and professional issues.
Anchor Bolts
Threaded bolt placed in grouted masonry unit opening. Used to fasten wood will, beam or other structural support to wall top.
Anchors
Metal or strap usually made of brass, stainless steel or galvanized steel. Anchors are used to tie a wall (brick, block or stone) to another structure.
Apprentice
Individual indenture (contracted) to a training program run by a Joint Apprenticeship and Training Committee (JATO) in the building trades.
Arch
A section of masonry work that spans an opening and supports not only its own weight, but also the weight of the masonry work above it.
B
Backer Rod
A flexible foam rod tubing either open or closed call used to maintain a constant joint design. It maintains two sided adhesion required for all proper sealant joints.
Barrier Masonry Walls
The modern masonry barrier wall is often single wythe construction where the exterior surface is designed to resist weather penetration.
Basket Weave Bond
Module groups of brick laid at right angles to those adjacent.
Bat (Batt)
A piece of brick usually half the full size or smaller.
Beaded Joints
See Movement Joints
Bed
The bottom side of a brick or block as it has been laid in the wall.
Bed Joints
Horizontal mortar bed on which a masonry unit has been laid.
Bevel
The incline of one surface of the same body with the angle being other than a right angle.
Bond
Pattern of laid masonry units; adhesion between mortar and masonry units; tying together parts of two or more wythes of masonry walls by overlapping masonry units.
Bond Beam
A bond beam is a horizontally reinforced element in a masonry wall that provides resistance to shear loads and also helps distribute lateral loads throughout the wall section.
Bond Stone
Stone or masonry unit that projects back from the facing wall into a backup wall. Bond stone is designed to tie the two walls or wythes together. A bond stone may not project completely through the two walls or wythes.
Boot Rod (sled runner)
A tool used to finish joints - a longer jointer with a wood handle used for bed joints.
Brick
A molded rectangular block of clay baked by the sun or in a kiln until hard and used as a building and paving material.
Brick Buggies
Carts used to covey material (palletized or packaged) on scaffolds or building floors either hand or power driven.
Brick Industry Association (BIA)
National trade association representing distributors and manufacturers of clay brick and suppliers of related products and services.
Brick Set/Bolster
A tool used for cutting brick. A brick set is beveled on one side and straight on the other.
Buttering
Place mortar on a masonry unit with a trowel.
C
Castables
Refractory material in a hydraulic setting bind.
Caulk (Caulking)
Sealing material, the process of sealing cracks around doors, windows and other cracks with a caulking gun.
Cavity Wall
A wall built in two wythes of masonry tied together with a continuous air space in between.
Cavity Wall Ties
Metal ties or bonding units used to tie together the wythes on a cavity wall.
Cell Clip
Cut brick piece or section.
Closure
Supplementary or short length used at corners or jambs to maintain bond patters.
Coarse Aggregate
Material predominantly retained on the No. 4 sieve.
Column
Vertical support member.
Compressive Strength
Another term for dead or live loads, vertical forces on a masonry structure.
Concave Joint
A mortar joint tooled with a round jointer. See Movement Joints.
Concrete
A hard, strong construction material consisting of sand, conglomerate gravel, pebbles, broken stone, or slag in a mortar or cement matrix.
Concrete Block
Concrete masonry units (CMU) are made from a combination of cementitious materials, aggregate, admixtures, and water.
Concrete Block Veneer
Material requirements for concrete veneer are the same as those for structural units.
Control Joint
Vertical joint made in the wall to allow for shrinkage movement. Used to prevent random cracking of the wall caused by contraction. See also expansion joint.
Corrugated Wall Ties
Galvanized strips of metal cut 1 inch wide in varying lengths. Used in wall reinforcing.
Crown
High point or apex of curving arch.
D
Dead Load
A type of vertical force applied on a wall by the weight of the building.
Deflection
Deviation from normal position or from zero.
Density
The quality of being dense, close or compact.
Dowels
A cylindrical piece of steel, either smooth or threaded used to hold stone in place. Dowels can be set in sealant, mortar or epoxy.
Drainage Cavity
The internal drainage cavity is designed to intercept any water that penetrates through the exterior wythe.
Drip
A projecting piece of material shaped to throw off water, prevent it from running down a wall or running back under a projection.
Dry Pressed Brick
Brick formed in molds under high pressure from relatively dry clay (5 to 7 percent moisture content).
Dry Saw
Dry cutting blade. If used without water can produce enormous amounts of dust.
E
Efflorescence
A deposit of white powder on the surface of masonry which comes from the leaching of water soluble salts in the masonry by evaporation of water.
Elastic
Ability of material to expand and contract.
Elliptical Arch
One of the strongest arches in brick masonry. It springs from a horizontal seat at and on the spring course, and the way its haunch crowns up adds to its strength.
Epoxy Mortar
Mortar of a thermosetting resins containing epoxy groups that are blended with other chemicals to form strong, hard chemically resistant mortar.
Expanded Shale, Clay and Slate
A ceramic lightweight aggregate prepared by expanding select minerals in a rotary kiln at temperatures over 1,000° (1,850° F).
Expanded Shale, Clay and Slate Institute (ESC
The international trade association for manufacturers of rotary kiln-produced expanded shale, expanded clay and expanded slate lightweight aggregate.
Expansion Joint
Vertical or horizontal joints used to separate masonry into segments to control cracking.
Extrude/Extrude Joints
To force clay through a die to give it shape - such as a brick. See Movement Joints.
F
Face
The exposed surface of a wall. Also the surface of a masonry unit to be exposed in finished work.
Ferrule
Metal band around the handle of the trowel at the shank end. Designed to protect the handle.
Fine Aggregate
Material that will almost entirely pass a No. 4 sieve, and be predominantly retained on the No. 200 sieve.
Flame Finish
The process of using a flame to pop off the surface of the stone face. This is performed only on granite and can be used both on interior and exterior stone.
Flashing
Sheet metal or plastic placed in mortar joints and air spaces in masonry for protection against water seepage.
Flemish Bond
A bond consisting of headers and stretchers alternating in every course and laid so that they always break the joint.
Flemish Header
In a flemish bond, a header is placed in the middle of the stretchers in the courses above and below.
Flush Joint
See Movement Joints
Foundation Ledge
A foundation ledge provides a positive water barrier at the floor level.
Furrowing
Small indentation cut into the mortar bed by a trowel to prepare the mortar bed for the brick.
G
Glazed Concrete Block
Ceramic or porcelainized glazes and/or mineral glazes used to face masonry units.
Gothic Arch
An arch with a rather high rise, with sides consisting of arcs of circles, the centers of which are at the level of the spring line. The Gothic arch is often referred to as a crop, equilateral, or lancet arch, depending upon whether the spacing of the centers are less than, equal to, or more than the clear span.
Grade
A predetermined percent of allowable imperfections for stone. Grades are used to create a scale to which stone can be sold and installed. Grade also limits the overall dimension that stone can be fabricated. The groups are granite-group A, marble-group B, marble-group C and marble-group D.
Granite
An igneous rock created deep within the earth. This rock is dense, difficult to create to final form, but is very durable.
Granular Insulation
A water-repellent or non-water absorbent fill material that pours readily into cores of masonry units or cavity type walls.
Grout
A cementitious component of highwater-cement ratio, permitting it to be poured into spaces within a masonry wall. Grout consists of Portland cement, lime and aggregate.
H
Hand Carts
Carts normally with two wheels which are used to manually handle or convey masonry units on the scaffold, building floors or around the project.
Head Joints
The vertical mortar joint between ends of masonry units. Often called cross joint.
Heel
Rear of the trowel blade.
Herringbone Pattern
A pattern of setting in which the units in a wall are laid aslant, instead of flat, with the direction of incline reversing in alternate courses, forming a zigzag effect. In floors of paving, the units are set at approximately a 45 degree angle with the boundary of the area being clad, alternate rows reversing direction to give a zigzag horizontal pattern, and the unit in one row filling the triangle between two units in the adjacent row.
High-lift Grouting
The technique of grouting masonry in lifts up to 12 feet.
I
Insulation
Material used to prevent the passage or leakage of heat, sound, etc. Comes in the form of board, granular fill or foam.
Interlock
An arrangement by means of which the functioning of one part is controlled by the functioning of another.
J
Jack Arch
Flat arch usually used for short spans.
Jamb
Vertical sides of an opening such as the side of a door or window.
Joint Reinforcement
Joint reinforcement will not prevent shrinkage cracks from occurring but will help to limit the growth or widening of cracks.
Journeyman
Craftsman or tradesman who has completed and passed an apprenticeship in a trade.
K
Kiln
Oven for firing brick or tile.
L
Ladder-type Wall Reinforcing
A type of horizontal wall reinforcement. A reinforcement system.
Lateral Force
Force placed on a structure by wind or earth pressure pushing laterally against a wall.
Level
A tool for determining, or adjusting a surface to an even horizontal plane.
Lift
Height of grout (or concrete) placed at one time from one pour.
Lightweight Aggregate
Aggregate of low density used to produce lightweight masonry, lightweight mortar, and lightweight grout, and includes expanded shale, clay, slate, and slag, pumice, volcanic cinders, scoria, tuff, and the end products of coal or coke combustion.
Limestone
Formed below water and compacted this is a highly concentrated crystalline calcium carbonate (calcite) but also contains silica, alumina, iron oxide and magnesia.
Lintel
Horizontal structural unit (beam) over an opening; support member over a door or window opening.
Live Loads
A type of vertical force, forces applied by the contents and occupants of a building.
Low-lift Grout
Grout must be placed into the walls after walls reach a certain height. Building of walls may continue only after grout is in place.
M
Marble
A metamorphic rock formed from limestone. This stone consists primarily of calcite and dolomite. Marble is a stone formed all over the world.
Mason
One who builds or works with stone or brick.
Mason Contractors Association of America (MCA
The national trade association representing masonry contractors and suppliers in national legislative and political affairs, codes and standards composition, workforce development, education, market promotion and general industry advocacy.
Masonry
That which is built by a mason; anything constructed of the materials used by masons, such as stone, brick, tiles, or the like.
Masonry Institute of America (MIA)
A promotion, technical and research organization established to improve and extend the use of masonry.
Masonry Standards Joint Committee (MSJC)
An organization composed of volunteers who through background, use, and education have acquired experience in the manufacture of masonry, or in the design and construction of masonry structures.
Miter
A joint formed by fitting together two pieces beveled to a specific angle (usually 45 degrees) to form a corner.
Monolithic
Without joints.
Mortar
Mortar performs many functions: it fills gaps between units, bonds the units together, provides weather protection.
Movement Joints
Movement joints are used to allow dimensional changes in masonry and to minimize random wall cracks and other distress.
N
National Concrete Masonry Association (NCMA)
Offers a variety of technical services and design aids through publications, computer programs, slide presentations and technical training.
Normal Weight Aggregate
Material such as sand, gravel, slag, crushed stone, etc.
O
Occupational Safety and Health Administration
A department of the U.S. Department of Labor to promulgate health and safety in the U.S. Establishes regulations and enforces such.
P
Parabolic Arch
The strongest of all arches. It has a gradual oval shape.
Parapet Flashing
It is important to install flashing at the parapet in two key locations: 1) under the coping stone, and 2) at the roof line.
Parging
Process of applying a coat of mortar to masonry construction, especially used for masonry walls. Also, the cement mortar coat itself.
Pier
A short masonry or concrete column supporting the foundations of the floor structure in spaces without a basement. Pier may be freestanding or bonded at its sides to other masonry or concrete. A masonry column used to support a garden wall. A freestanding column.
Pilaster
A pier or column forming part of a masonry or concrete wall, partially projecting from it and bonded to it. Designed to receive joist or beam load.
Plaster
Used in interior stone installations to adhere the anchors in place as well as to fill butt jointed stone.
Plastics
Refractory brick in a plastic-like moldable consistency.
Plumb
Exactly vertical. Measured with a plumb line.
Point
Tip of the trowel blade.
Polish
A mechanical method creating a glossy smooth finish on stone. Generally marbles and granites can be polished to expose the full grain and color of the piece.
Polystrence
A tough, clear, colorless plastic material.
Porous
Materials ability to absorb water having many small openings.
Portland Cement
Fine, grayish powder formed by burning limestone, clay or shale and then griding the resulting clinkers. The result is a cement which hardens under water and which is used as a base for all mortar. Portland cement is a grade of cement, not a brand.
Portland Cement Association (PCA)
The Portland Cement Association represents cement companies in the United States and Canada through market development, engineering, research, education and public affairs programs.
Prism
A small assemblage made with masonry units and mortar and sometimes grout. Primarily used to predict the strength of full scale masonry members.
Puddling
The process of settling or consolidating grout in a masonry reinforced wall to prevent the formation of voids.
Q
Quarry Sap
The water present in block stone when removed from the ground. Quarry sap seasons out anywhere from sixty days to eight months, depending on the type of stone.
Quoin
Large squared stone or brick set at the corner formed by two masonry walls. Projects out from the corner in some cases.
R
Racked Joint
See Movement Joints
Racking
Laying or stepping back each higher masonry course.
Rebar
Horizontal or vertical reinforcing bars used to reinforce a masonry structure.
Refractory
Any non-metal material or object that can withstand high temperature without becoming soft.
Reinforcing
To strengthen a structure by the addition of something to that structure.
Rock
A wide variety of natural minerals found in virgin form on or below the surface of the earth.
Roman Arch
A semicircular arch. If built of stone, all units are wedge-shaped.
S
S-Jointer
A shorter jointer used for head joints.
Safety Data Sheets (SDS)
Documents describing the known hazards associated with a material.
Sample Panel
A test panel designed to 1) demonstrate the quality of materials and the kind of workmanship that will be used through-out the construction period or 2) be observed throughout construction of the job for any change or damage as a result of changes in weather conditions.
Sandstone
Generally quartz based, cemented together with a high percent of silica, sandstone also contains calcium, carbonate and iron compounds, this stone generally is formed without sediment grains.
Sealant
Silicone, polyurethane or polysulphate based chemicals with elastomeric (elastic) characteristics used at various conditions in stone joints.
Segmental Arch
Similar to semi-circle arch. Segment of a circle.
Semi-Circle Arch
See Roman Arch
Shank
Connect the trowel blade to the trowel handle.
Silica
A white or colorless compound (SiO2) occurring as quartz, sand, flint, agate, and many other minerals.
Sill
Bottom of a window or door frame. Skew. To twist back or lean; to incline. Shoring Jacks. Support masonry lintels.
Sled Runner (Boot Rod)
A longer jointer with a wood handle used for bed joints.
Soft Mud Process
A brick manufacturing process using a soft brick soffit.
Span
Distance between two supports.
Spring Line
For minor arches, the line where the skewback cuts the soffit. For major parabolic arches, the term commonly refers to the intersection of the arch axis with the skewback.
Stiff Mud Process
A process through which bricks are made.
Stinger
A long cable that powers the mechanical vibrator used to consolidate grout.
Stone
Term used to discuss rock in a semi or finished form to be used in constructions or landscaping.
Stone Veneer
Stone veneer simulates full depth, load-bearing stone construction.
Struck Joint
See Movement Joints
Structural Backup
The structural backup of the building system is designed to support floor and roof loads and to resist lateral wind loads and seismic movement.
Structural Clay Tile
Hollow masonry building units composed of burned clay, shale, fire clay or mixtures thereof.
Substrate
Tensile strength forces that separate the masonry unit from mortar.
T
Terra Cotta
A hard semifired waterproof ceramic clay used in pottery and building construction.
The Masonry Society (TMS)
An international gathering of people interested in the art and science of masonry.
Toothing
Temporary wall end where alternate stretchers project out. Projecting masonry units are called tooths.
Trowel
A flat-bladed hand tool for leveling, spreading, or shaping substances such as cement or mortar.
Truss-Type Wall Reinforcing
A type of horizontal reinforcing systems made with diagonal cross rods through wall flashing.
Tutor Arch
A pointed, four-centered arch of medium rise-to-span ratio.
V
Vapor Retarder
Vapor retarders minimize the movement of moisture from the interior of the building into the cavity wall where condensation can degrade insulation and structural members.
Vee Joints
See Movement Joints
Veneer Lintels, Shelf Angles
Lintels provide support of brickwork over masonry openings and are supported by bearing on masonry at the jambs on either side of the opening.
Veneer Ties
Used to anchor veneer to walls - comes in many styles or types.
Vertical Force
See dead or live loads.
Vertical Reinforcement
Vertical reinforcement is used in masonry walls to resist tensile stresses that may arise from flexural and shear loads.
Voussoir
One of the wedge-shaped masonry units which form the arch ring. An example is a brick in a jack arch.
W
Wall Caps
Wall caps and flashing directly beneath the cap must be impervious to moisture penetration.
Water-Resistive Barrier
Water resistive barriers are required over stud wall construction.
Weathered Joint
See Movement Joints
Weeps
Openings placed in mortar joints of facing material at the level of flashing, to permit the escape of moisture.
Wet Saw
A wet cutting diamond blade. Used on a saw that has a continual water pump supply on the blade keeping the blade clean and cool.
Winning
The process used to mine raw materials used for manufacturing brick.
Wythe
Vertical wall or tier of masonry units one-unit thick. The thickness of masonry separating flues in a chimney. Also called a withe or tier.
Z
Z-Ties
A wall tie made with a 90 degree angle and a 2-inch leg on each side.
