Architectural and Engineering Glossary


Y-branch, Wye Branch

In a plumbing system, a branch in the shape of the letter Y.


See wye (Y) connection.

Y-fitting, Wye Fitting

A pipe fitting,1,one end of which subdivides,forming two openings at an angle, usually 45to the run of pipe.


Same as wye level.


A type of tracery in which the mullions split in the shape of the letter Y.

Yale Lock

A proprietary name for a cylindrical lock.

Yankee Barn

A steeply pitched, timber framed, side gabled wood barn of post-and-lintel construction, often with a gambrel roof; usually having no forebay; typically built against a hill side with animals housed at ground level on the lower side adjacent to the barn; similar to a bank barn.


That part of a building plot not occupied by the building, open to the sky.

Yard Drain

A surface drain; used to clear  an open area of surface water.

Yard Line

That section of a consumer’s gas piping and fittings that extends from the point of service, 3 (i.e., point of delivery) to the house piping.

Yard Lumber

Lumber up to 5 in. (12.5 cm) thick intended for general building construction.


1.The number of cubic yards excavated or filled. 2.An area or surface, expressed in square yards.


Abbr. for “yard.”

Year Ring

Same as annual ring.

Yellow Fir

See Douglas fir.

Yellow Metal

Same as Muntz metal.

Yellow Ocher, Yellow Ochre

A form of earth used as a yellow pigment; limonite.

Yellow Pine

A hard resinous wood of the longleaf pine tree, having dark bands of summer wood alternating with lighter colored springwood; used as flooring and in general construction.

Yellow Poplar, Poplar

A moderately low density, even textured hardwood of the central and southern US; color varies from white to yellow, tan, or greenish brown; used for veneer, plywood, and lumber core for cabinetwork.


The development of a yellow color or cast in white or clear coatings after aging.


A bundle of reeds or combed straw used as thatching material for a roof.


A term for a massive gate, such as a portcullis, chiefly used in Scotland.


1.The volume of freshly mixed concrete produced from a known quantity of ingredients; volume yield.2.The number of product units, such as blocks, produced per bag of cement or per batch of concrete.

Yield Point

The lowest stress in a material (less than the maximum attainable stress) at  which  the material begins to exhibit plastic properties; beyond this point an increase in strain occurs without an increase in stress.

Yield Strain

The level of strain at which steel starts to show substantial plastic deformation. 

Yield Strength

The stress at which a material exhibits a specified limiting deviation from the proportionality of stress to strain.


1.A horizontal framework around the formwork for a column. 2.The horizontal piece forming the head of a window or door frame.3.In plumbing, a two way coupling for pipes, in the shape of the letter Y. 4.A yoke vent.

Yoke Relief Vent, Yoke Vent

2.1.A pipe connecting upward from a soil stack or waste stack to a vent stack for the purpose of preventing pressure changes in the stack. 2.A vertical or 45relief vent of the continuous waste and vent type formed by the extension of an upright wye branch or 45wye branch inlet of the horizontal branch to the stack; becomes a dual yoke vent when two horizontal branches are thus vented by the same relief vent. 3.A vent connected to a soil or waste  stack that continues upward to the connection with the vent stack for the purpose of reducing pressure changes in the stack

Yorkshire Bond

Same as monk bond.

Yorkshire Light

A window having one or more fixed sashes and a movable sash which slides horizontally.

Young’s Modulus

In an elastic material which has been subject to strain below its elastic limit,the ratio of the tensile stress to the corresponding tensile strain.


On drawings,abbr.for yield point.


On drawings, abbr. for “year.”


On drawings, abbr. for yield strength.


A circular tent like dwelling used in northern Asia; can be readily dismantled, moved, and reassembled at another site; primarily constructed of a felt like material and/or skins that are stretched over a wood framework.