Architectural and Engineering Glossary

G

GL

On drawings,abbr. for glass. 

Glacial Till

See till.

Glacis

A sloped embankment in front of a fortification,so raised as to bring an advancing enemy into the most direct line of fire.

Gland Joint

In hot water piping,a joint that permits movement resulting from thermal expansion or contraction.

Gland Seal

A seal used to prevent leakage between a fixed part and a movable part.

Glare

The sensation produced by brightnesses within the visual field that are sufficiently greater than the luminance to which the eyes are adapted to cause annoyance,discomfort,or loss in visual performance and visibility.

Glass Bulb Sprinkler

In a fire protection system,a sprinkler which opens under the influence of heat by the breakage of a glass bulb;the bulb breaks as a result of the pressure exerted by the expansion of the liquid which it contains.

Glass Cement

Any binding material used to cement glass to another piece of glass or other material.

Glass Cloth

A closely-woven cloth fabricated of glass fibers;often used as a finishing jacket over thermal insulation for piping.

Glass Concrete

A concrete slab or panel in which individual translucent glass lenses have been set,usually in a geometric pattern,to permit passage of light.

Glass Cutter

A hand tool used for scoring or cutting glass;consists of a small,sharp wheel of hardened steel which is set in a handle,or a tool with a diamond point.

Glass Door

A door of thick,heat-strengthened or tempered glass;there are no rails or stiles.

Glass Fiber, Glass Fibre

See fiberglass.

Glass House

1.British term for greenhouse.2.A residence having exterior walls which are almost completely glass;an outstanding example is Philip Johnson’s glass house in Connecticut.

Glass Paper

A type of fine sandpaper,made with powdered glass as the abrasive.

Glass Pipe

A pipe fabricated from a low-expansion borosilicate glass having a low alkali content;used primarily for the drainage of various corrosive liquids;very brittle and therefore used only where protection is provided against mechanical damage to the pipe.

Glass Reinforced Concrete

Concrete that has been reinforced by the addition of glass fibers to the concrete mix.

Glass Seam

A fracture in limestone that has been recemented and annealed by deposition of transparent calcite;limestone containing such a seam is structurally sound.

Glass Silk

Same as glass wool.

Glass Size

The size of a piece of glass required for glazing a given opening,allowing suitable clearance between the edge of the glass and the rebate.

Glass Slate

Same as glass tile.

Glass Stop

A glazing bead.2.A fitting which holds the lower end of a patent glazing bar;prevents the pane from sliding down.

Glass Surface Coating

1.A coating applied to a glass surface,usually to tint the glass a desired color or to control the amount of solar radiation that is transmitted through the glass.The coating may be applied as the molten glass passes along a long continuous oven;alternatively,the coating may result from dipping the glass into a chemical solution,and then drying and firing it.2.A metal coating evaporated on a surface while it is under a vacuum.
 

Glass Tile, Glass Slate

Tile fabricated of translucent or transparent glass;installed in a roof surface to allow light to enter the room below.

Glass Wool,glass Silk

Spun glass fibers in bulk form;resembles wool;used as thermal insulation,in air filters,and in fabricating fiberglass blankets,boards,and tile.Also see mineral wool,fiberglass.

Glaze

1.A ceramic coating,usually thin,glossy,and glass-like,formed on the surface of pottery,earthenware,etc.2.The material from which  the ceramic coating is made.3.To install glass in windows,doors,storefronts,curtain walls,and various other segments of building construction.

Glaze Coat

1.In built-up roofing having a smooth surface,the top layer of asphalt.2.A temporary coating of bitumen used to  protect the plies of built-up roofing when the application of the top pouring and surfacing is delayed.3.A layer of thin,almost transparent,colored paint which allows an undercoat to show through.
 

Glazed

1.Said of an opening that is filled with sheets of glass,as in a window.2.Said of a finish that is composed of ceramic materials fused into its surface,usually making it essentially impervious to moisture.

Glazed Block

A concrete block that has been glazed on one side,thereby providing the side with a smooth,hard surface;often colored.

Glazed Brick

A brick that has been fired in a kiln hot enough to fuse the clay and sand on its surface,usually forming a dark glassy coating.

Glazed Interior Tile

A glazed ceramic tile having a body that is suitable for interior use,usually nonvitreous;not fabricated for use under conditions of excessive impact or of freezing and thawing.

Glazed Tile

Ceramic tile having a fused impervious glazed surface finish (clear, white,or colored) composed of ceramic materials fused into the body of the tile;the body may be nonvitreous,semivitreous,or impervious.

Glazed Work

Brickwork built with enameled brick or glazed brick.

Glazement

A waterproof surfacing applied on a masonry surface.

Glazier’s Chisel

A putty knife shaped like a chisel,used in setting glass.

Glazier’s Point, Sprig

A thin small three or four-cornered piece of sheet metal,used to hold a pane of glass in a window frame while putty is applied.

Glazier’s Putty

A type of glazing compound.Also see putty.
 

Glazing

1.Setting glass in an opening.2.The glass surface of a glazed opening.

Glazing Bar

One of the vertical or horizontal bars within a window frame which hold the panes of glass;a muntin.

Glazing Bead, Glass Stop

1.Same as bead,3.2.At a glazed opening,removable trim that holds the glass firmly in place.

Glazing Block

Same as setting block.

Glazing Brad

Same as glazier’s point.

Glazing Clip

A metal clip used to retain a pane of glass in a metal frame while glazing compound is applied.

Glazing Color

A transparent wash,used to cover a ground coat of paint.

Glazing Compound

A putty-like material used to seal window glass in place;differs from putty,1 in that it retains its plasticity for an extended period of time.

Glazing Fillet

A small strip of wood used to hold glass in a rebate;a glass stop.

Glazing Gasket

A prefabricated strip of material used to seal and secure glass,or sealed glazing units,into frames and openings by a dry glazing method without using compounds or tapes.

Glazing Molding

1.A molding which serves as a glazing fillet.2.A glass stop, 2.

Glazing Point

Same as glazier’s point.

Glazing Rabbet, Glazing Rebate

A rabbet,3 that receives the glass in a window frame or glazing bar.