• Apron Wall: That part of a panel wall between window sill and wall support.
• Area Wall: 1. The masonry surrounding or partly surrounding an area. 2. The retaining wall around basement windows below grade.
• Bearing Wall: One which supports a vertical load in addition to its own weight.
• Cavity Wall: A wall built of masonry units so arranged as to provide a continuous air space within the wall (with or without insulating material), and in which the inner and outer wythes of the wall are tied together with metal ties.
• Composite Wall: A multiple-wythe wall in which at least one of the wythes is dissimilar to the other wythe or wythes with respect to type or grade of masonry unit or mortar
• Curtain Wall: An exterior non-loadbearing wall not wholly supported at each story. Such walls may be anchored to columns, spandrel beams, floors or bearing walls, but not necessarily built between structural elements.
• Dwarf Wall: A wall or partition which does not extend to the ceiling.
• Enclosure Wall: An exterior non-bearing wall in skeleton frame construction. It is anchored to columns, piers or floors, but not necessarily built between columns or piers nor wholly supported at each story.
• Exterior Wall: Any outside wall or vertical enclosure of a building other than a party wall.
• Faced Wall: A composite wall in which the masonry facing and backings are so bonded as to exert a common reaction under load.
• Fire Division Wall: Any wall which subdivides a building so as to resist the spread of fire. It is not necessarily continuous through all stories to and above the roof.
• Fire Wall: Any wall which subdivides a building to resist the spread of fire and which extends continuously from the foundation through the roof.
• Foundation Wall: That portion of a loadbearing wall below the level of the adjacent grade, or below first floor beams or joists.
• Hollow Wall: A wall built of masonry units arranged to provide an air space within the wall. The separated facing and backing are bonded together with masonry units.
• Insulated Cavity Wall: See "SCR insulated cavity wall".
• Loadbearing Wall: A wall which supports any vertical load in addition to its own weight.
• Non-Loadbearing Wall: A wall which supports no vertical load other than its own weight.
• Panel Wall: An exterior, non-loadbearing wall wholly supported at each story.
• Parapet Wall: That part of any wall entirely above the roof line.
• Party Wall: A wall used for joint service by adjoining buildings.
• Perforated Wall: One which contains a considerable number of relatively small openings. Often called pierced wall or screen wall.
• Shear Wall: A wall which resists horizontal forces applied in the plane of the wall.
• Single Wythe Wall: A wall containing only one masonry unit in wall thickness.
• Solid Masonry Wall: A wall built of solid masonry units, laid contiguously, with joints between units completely filled with mortar or grout.
• Spandrel Wall: That part of a curtain wall above the top of a window in one story and below the sill of the window in the story above.
• Veneered Wall: A wall having a facing of masonry units or other weather-resisting non-combustible materials securely attached to the backing, but not so bonded as to intentionally exert common action under load.

WALL PLATE
A horizontal member anchored to a masonry wall to which other structural elements may be attached. Also called head plate.

WALL TIE
A bonder or metal piece which connects wythes of masonry to each other or in other materials.

WALL TIE, CAVITY
A rigid, corrosion-resistant metal tie which bonds two wythes of a cavity wall. It is usually steel, 3/16 in. in diameter and formed in a "Z" shape or a rectangle.

WALL TIE, VENEER
A strip or piece of metal used to tie a facing veneer to the backing.

WATER RETENTIVITY
That property of a mortar which prevents the rapid loss of water to masonry units of high suction. It prevents bleeding or water gain when mortar is in contact with relatively impervious units.

WATER TABLE
A projection of lower masonry on the outside of the wall slightly above the ground. Often a damp course is placed at the level of the water table to prevent upward penetration of ground water

WATERPROOFING
Barrier which prevents the flow or passage of moisture through porous materials (masonry, concrete, etc.) due to water pressure. It can be succesfully designed for either below or above grade construction.

weath·ered; weath·er·ing/'we[th]-ri[ng], 'we-[th]&-/
Date: 15th century
transitive senses
weathering The action of the elements on a rock in altering its colour, texture, or composition, or in rounding off its edges. 1. Exposure to the open air and / or subject to the action of the elements, with the result of alteration of color, texture, composition, or form of exposed objects; specifically : the physical disintegration and chemical decomposition of materials; aging
2. Alternatively used as a noun to describe a slight construction slope designed to throw off rainwater
3. Changes on the surface of glass caused by chemical reaction with the environment. Weathering usually involves the leaching of alkali from the glass by water, leaving behind siliceous weathering products that are often laminar.
4. Response of materials (which were once in equilibrium within earth's crust) to new conditions at or near contact with air, water, or living matter. Also

• chemical weathering: disintegration, a process by which rock is broken down into smaller and smaller fragments as result of energy developed by physical forces.
• mechanical weathering: chemical weathering - Weathering of rock material by chemical processes that transform original material into new chemical combinations. Thus chemical weathering of orthoclase produces clay, some silica, and a soluble salt of potassium.

WEEP HOLES
Openings placed in mortar joints of facing material at the level of flashing, to permit the escape of moisture.

Wind, like stack effect, is a natural phenomenon. Wind increases the positive air pressure acting against a building on the windward side, and produces a negative pressure on the leeward side and on the walls parallel to the wind direction. The wind also exerts a suction on flat or low-sloped roofs and a positive pressure on the windward side of steeper-sloped roofs

WITH INSPECTION
Masonry designed with the higher stresses allowed under EBM. Requires the establishing of procedures on the job to control mortar mix, workmanship and protection of masonry materials.

WITHOUT INSPECTION
Masonry designed with the reduced stresses allowed under EBM.

WYTHE
1. Each continuous vertical section of masonry one unit in thickness.
2. The thickness of masonry separating flues in a chimney. Also called withe or tier.

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