Architectural and Engineering Glossary



1.See blistering,1.2.In plastering,a localized condition of checking,3.

Tuscan Order

One of the five Classical orders;a simplified version of the Roman Doric order to which it is similar,but has fewer and bolder moldings,unfluted columns,a plain frieze,and no triglyphs;its only decorative details are moldings.

Tuscan Revival

A term descriptive of late 17-century architecture that emulates and borrows features from the Tuscan order.

Tuscan Villa Style

A style somewhat similar to that of villas in the Italianate style, boxlike in shape but having a symmetrical plan rather than an asymmetrical plan and a flat roof;frequently a square belvedere at the center of the roof;windows often round-headed.


1.A beveled shoulder on a tenon to provide additional strength,the mortise being cut correspondingly.2.A stone or brick in toothing.

Tusk Nailing

See toenailing.

Tusk Tenon

A tenon strengthened by having one or more steps on its lower side;the shoulder above may be beveled.


See pane.

Twin Archway

An opening having two archways which are side-by-side.

Twin Brick

Same as double-sized brick.

Twin Cable

A cable consisting of two individually insulated electric conductors,laid parallel;either bound together in a common outer protective covering or attached to each other by insulation.Also see duplex cable.

Twin-filament Lamp

An incandescent lamp with two filaments that are wired independently. 

Twin-twisted Bar Reinforcement

Two reinforcement bars having the same nominal diameter,twisted together.

Twining Stem Molding

A common Norman molding consisting of a half round entwined by a stylized tendril.


A warped board in which the four corners of one face are not in the same plane;a spiral distortion.

Twist Drill

A drill,with one or more helical cutting grooves;used for drilling holes in metal,wood, etc.

Twisted Column

See wreathed column. 

Twisted Grain

Same as interlocked grain. 

Twisted Pair

Two insulated electrical conductors,twisted together without a common covering.

Two-and-one-half-story House

A two-story house in which the loft space between the ceiling of the second floor and the roof above is provided with natural light and ventilation either by dormers and/or by windows in the gable end walls.

Two-bay Cottage

A Cape Cod house having a façade with two windows on each side of the front door;also called a full Cape house.


A piece of timber,nominally 2 in. (5 cm) thick by 4 in. (10 cm) wide,but actually 15⁄8  in. by 35⁄8  in.(4.13 cm by 9.21 cm).

Two-centered Arch

A pointed arch whose inner surface is struck from two centers; the shape of the arch is determined by the position of the centers of curvature and radii of curvature of the two arcs of circles that are joined;also see equilateral arch.

Two-coat Work

In plastering,the application of a first coat (the base coat) followed by a second (the finish coat).

Two-family House

A two story house having two separate living quarters,with a separate entrance for each.

Two-hinged Arch

An arch with hinges at the supports at both ends.

Two-light Window

1.A window with two panes.2.A window which is two panes high or two panes wide.3.A gemel window.


Descriptive of a double hung window having two panes in the upper sash and two panes in the lower sash;see pane.

Two-part Adhesive

An adhesive that requires the addition of an accelerator to the resin,in order to set,e.g.,see epoxy.

Two-point Latch

A type of door latching device;sometimes used where it is necessary to lock the inactive leaf of a pair of doors at top and bottom.

Two-point Suspension Scaffold

Same as swinging scaffold.

Two-pour System

Concrete that is poured at two different times;compare with monolithic pour system.

Two-room Plan

A relatively common floor plan for a simple two-room dwelling in colonial architecture of New England,the mid-Atlantic area,and the South.This plan has many variations but usually consists of an all-purpose main room (the hall) and an adjacent room (the parlor) containing the best furniture and a bed for  the parents.Also see hall-and-parlor plan.

Two-stage Curing

A process in which concrete products are cured in low pressure steam,stacked,and then autoclaved.See cure;auto clave.

Two-tiered Porch

A two story porch,each of which is virtually identical.

Two-way Draw

Said of a drapery that parts in the middle and can be drawn to each side.

Two-way Joist Construction

Floor or roof construction in which two mutually perpendicuar systems of parallel beams,in a horizontal plane,are used to support the floor or roof.

Two-way Reinforcement Reinforcing Bars

arranged in a grid pattern,so that the sets of bars are at right angles to each other.

Two-way Slab

1.A concrete floor slab in which the main reinforcement runs in two directions.2.A rectangular,reinforced concrete slab having a span on the long side that is less than twice the span on the short side.

Two-way-reinforced Footing

A footing in which the reinforcement runs in two directions,usually perpendicular to each other.


1.The triangular or segmental space enclosed between the horizontal cornice of a pediment and the underside of the raking or curved cornice above;sometimes decorated with decorative elements,sculpture,or a window.2. Any space similarly marked off or bounded,as between the lintel of a door and the arch above.


On drawings,abbr.for “typical.”

Type-DWV Tubing

A copper tubing which has thinner walls than other types of copper tubing;used primarily for drainage,waste,and vent lines. 

Type-S Fuse

A fuse contained in a small glass or ceramic housing,which can be screwed into a screw-shell socket;it has a window for observing whether the fuse has been “blown”;available in three,noninterchangeable sizes(15, 20, and 30amperes).

Type-X Gypsum

wallboard A gypsum wall board which is especially manufactured to provide specific fire resistant characteristics.

Type-X Gypsum Lath

A gypsum lath which is especially manufactured to provide specific fire resistant characteristics.

Tyrolean Finish

A rough plaster finish obtained by flinging plaster on a wall with a hand operated machine.