Gabion Wall: A retaining wall or structure made of wire cages or baskets filled with rock, concrete, or sometimes sand and soil.

Gable: The end of a building, as distinguished from the front or rear. Also, the triangular end of an exterior wall from the level of the eaves to the ridge of a double-sloped roof.

Gambrel Roof: A type of roof whose slope is broken by an obtuse angle so that the lower slope is steeper than the upper slope; a double-sloped roof having two pitches.

Garbage: The animal or vegetable waste resulting from preparation or consumption of food.

Gas Sorption: Devices used to reduce levels of airborne gaseous compounds by passing the air through materials that extract the gases. The performance of solid sorbents is dependent on the airflow rate, concentration of the pollutants, presence of other gases or vapors, and other factors.

Gasket: A weatherstripping material that seals gaps and openings in windows and doors. It’s typically rubber or silicone material.

Girder: A main horizontal beam made of steel, reinforced steel, or wood upon which floor joists rest and used to support other structural members or concentrated loads at isolated points along its length.

Glass Pane: A transparent or translucent panel typically set within a door. A common source of water infiltration if the gasket fails.

Grab Bars: Vertical or horizontal handholds above the height of the ladder for the user’s safe transition to a landing.

Gravity Retaining Wall: A type of retaining wall designed to hold back soil primarily through its own weight without additional reinforcement.

Grease: Animal fat, vegetable shortening or oil used in preparing food or resulting from cooking.

Grille: A component of the ventilation system that returns air to the HVAC system.

Ground-Fault Circuit Interrupter (GFCI): A device intended for the protection of personnel that functions to de-energize a circuit.

Grounded: Connected to the earth or to some conducting body that serves in place of the earth.

Grounded, effectively: Intentionally connected to the earth through a ground connection or connections of sufficiently low impedance, and having sufficient current-carrying capacity to prevent the buildup of voltages that might otherwise result in undue hazards to connected equipment or to persons.

Grounding Electrode: A device that establishes an electrical connection to the earth.