Glossary, 68 terms
Home inspection terms: G
Each definition is the Key Term from the lesson named under it. Where two lessons define a term for different uses, both are here.
- Gabion retaining wall
- A wire cage or basket filled with rubble or natural stone.
Lesson 2A, Site Scope, Terms and Retaining Walls - Gable roof
- A triangle-shaped roof style, with ceiling joists as the base and rafters as the legs.
Lesson 13A, Roof and Ceiling Framing, Rafters, Ties and Purlins - Galvanic corrosion
- Corrosion from electrons flowing between dissimilar metals through an electrolyte such as moisture; the technically correct term.
Lesson 34B, Pipe Supports, Copper, CPVC, Galvanized Steel and PEX - Galvanic reaction
- A reaction between different metals in contact with moisture present, which may cause electricity to flow; also called electrolysis.
Lesson 25B, Older Wiring: Knob and Tube, Cloth NM and Aluminum - Galvanized steel pipe
- Zinc-coated steel pipe used in houses from about 1860 to 1960, with an expected service life of about 50 years.
Lesson 34B, Pipe Supports, Copper, CPVC, Galvanized Steel and PEX - Gambrel
- A less common roof style, often associated with barns.
Lesson 13A, Roof and Ceiling Framing, Rafters, Ties and Purlins - Gapping
- Spaces opening between floor boards.
Lesson 17B, Interior Doors and Floor Coverings - Garage
- A structure with a door that a vehicle may be driven through.
Lesson 7, Garage Vehicle Doors and Operators - Garage door opener (opener, vehicle door operator)
- An electric motor-driven device that opens and closes a garage vehicle door by switches and radio remote control.
Lesson 7, Garage Vehicle Doors and Operators - Garbarator
- A Canadian name for a food-waste disposer.
Lesson 41A, Appliance Scope and Terms, Cooktops, Ranges, Ovens and Dishwashers - Gas control valve
- The valve that admits gas to the combustion chamber and connects to the sensors.
Lesson 36B, Electric and Gas Storage Tank Water Heaters - Gas log lighter
- A gas pipe with holes, directly above the hearth, used to start wood fires.
Lesson 39A, Fireplace Types and Terms, Firebox, Hearth and Clearances - Gas meter
- The utility's device that records how much gas a building uses.
Lesson 38H, Gas Meters, Regulators, Sizing, Leak Detection and Propane Tanks - Gas pack
- 1. A gas-fired package heating and cooling system.
Lesson 19D, System Descriptions and Inspection Methods - 2. A package system pairing a gas-fired furnace with an air conditioning system.
Lesson 28B, Cooling Systems: Inspecting Equipment and Typical Defects - Gas regulator
- The utility's disk on the meter's inlet side that lowers the supply pressure to the level houses in the area use.
Lesson 38H, Gas Meters, Regulators, Sizing, Leak Detection and Propane Tanks - Gas shutoff valve
- A valve that shuts off the gas to a building or to one appliance.
Lesson 38G, Other Gas Pipes, Connectors, Valves and Gas Pipe Installation - Gasket
- A flexible seal on a shower door or glass surround.
Lesson 35B, Showers and Tub/Showers - Gate valve
- A full-open valve whose metal gate a wheel and screw move up and down; its fair seal can degrade with age.
Lesson 34C, PB, Brass and Lead Pipe, Water Connectors and Valves - GEC
- Grounding electrode conductor, the conductor connected to the grounding electrode.
Lesson 24A, Service Equipment, Enclosures and Panelboards - General liability (GL) insurance
- Insurance that pays for damage or personal injury caused by the home inspector during an inspection.
Lesson 21B, Contracts and Insurance - Generator
- A machine that supplies electricity to a house when utility electricity is interrupted, or all or part of the electricity to an off-the-grid house.
Lesson 27A, Smoke and Carbon Monoxide Alarms, Load Controllers and Generators - Geotechnical engineer
- An engineer whose specialty is foundation problems from poor soil.
Lesson 11B, Forces and Soils, Footings, Piers and Columns - GFCI
- 1. Ground fault circuit interrupter, a type of OPD.
Lesson 24A, Service Equipment, Enclosures and Panelboards - 2. Ground fault circuit interrupter; a breaker or receptacle that trips on a ground fault to protect personnel from shock.
Lesson 24B, Overcurrent Protection, GFCI and AFCI - 3. Ground fault circuit interrupter.
Lesson 33A, Electric Heating Systems - Ghost flushing
- Tank refilling caused by a leaking flush valve.
Lesson 35D, Toilets and Bidets - Ghosting
- A name sometimes used for a door that moves when left partly open.
Lesson 5A, Exterior Doors and Safety Glazing at Doors - Glazier points
- Small metal triangles that hold the glass of an older wood sash from the outside.
Lesson 5B, Windows, Window Flashing, Glazing, Window Wells, Escape Openings and Fall Protection - Glazing putty
- The compound that covers the bars over glazier points.
Lesson 5B, Windows, Window Flashing, Glazing, Window Wells, Escape Openings and Fall Protection - Globe valve
- A valve that closes by seating a stopper between two baffles; it gives good flow control and is not full-open.
Lesson 34C, PB, Brass and Lead Pipe, Water Connectors and Valves - Glue laminated lumber (GLL)
- Engineered wood compressed with glue, heat, and pressure and made with a camber; also called gluelams.
Lesson 12B, I-Joists, SCL, Glulam and Floor Trusses - Gooseneck
- A curved handrail piece that joins a stairway handrail to a landing newel in one continuous vertical connection.
Lesson 18A, Stairs, Ramps, Handrails and Guards - Gooseneck fitting
- The fitting usually used to end an oil vent pipe outdoors.
Lesson 38I, Oil Supply, Valves, Filters and Tanks - Grade
- 1. The level, or elevation, of the ground around the exterior of the house.
Lesson 2A, Site Scope, Terms and Retaining Walls - 2. The ground near a house, established to separate framing and wall coverings from earth and hard surfaces and to divert water from the foundation.
Lesson 2B, Grade, Drainage and Vegetation - Grade (lumber)
- The quality rating of lumber.
Lesson 12A, Floor Framing, Spans, Bearing, Notching and Boring - Grade D paper
- 1. A paper used as the water-resistive barrier behind cement stucco.
Lesson 4B, Fiber Cement, Hardboard, Insulbrick, Stucco, EIFS, Vinyl, Wood and Wood Structural Panel Siding - 2. Kraft paper saturated with asphalt, used as a WRB.
Lesson 15A, Insulation Defects, Water-Resistive Barriers, Radiant Barriers and Fenestration - Grading
- Shaping the property to a desired elevation by moving soil or other material.
Lesson 2A, Site Scope, Terms and Retaining Walls - Grate
- A raised metal platform that holds the logs.
Lesson 40A, Factory-Built Fireplaces and Chimneys - Gravel stop edge flashing
- Flashing at a BUR edge where water drains off, which helps prevent loss of ballast.
Lesson 9A, Low Slope Roofing: Built-Up Membranes and Roll Roofing - Gravity distribution
- A heat distribution method with no fan and no filter that moves heat by convection and the stack effect.
Lesson 31A, Gas Appliance Categories and Gas Forced-Air Furnaces - Gravity-flush
- A flush moved by tank water from above and gravity from below.
Lesson 35D, Toilets and Bidets - Gray water
- Liquid waste from bathtubs, showers, lavatories, laundry trays, and clothes washers.
Lesson 34A, Plumbing Scope and Plumbing Terms - Gray water recycling system
- A system that filters fixture discharge and reuses it for toilet flushing or irrigation.
Lesson 38D, Septic Systems - Gray water system
- A system that reuses fixture waste water to flush toilets or water landscaping.
Lesson 34A, Plumbing Scope and Plumbing Terms - Green board (green drywall)
- Drywall whose paper has some water-resistant properties.
Lesson 17A, Interior Walls, Ceilings, Drywall, Plaster and Trim - Grid-connected system (grid-tied, utility-interactive)
- A PV or wind system connected to the utility grid.
Lesson 27B, Alternative Energy Systems: Solar PV, Wind and Solar Water Heating - Grille
- 1. A cover with fixed louvers or perforations that cannot be closed, usually over a return air opening, though it may also sit over a supply opening.
Lesson 28A, Cooling Systems: Understanding the System - 2. The cover over a floor furnace opening, through which the furnace distributes heat.
Lesson 31B, Floor and Wall Furnaces, Room Heaters and Unvented Appliances - Grinder pump (grinder ejector)
- The more common sewage ejector type, which reduces the material in size as it discharges.
Lesson 38E, Sewage Ejectors, Backwater Valves and Sump Pumps - Gross negligence
- The less common class of negligence, defined by some as not exercising even slight care and by others as an act or omission, done consciously, that recklessly disregards a legal duty.
Lesson 21A, Business Law, Claims and Liability - Ground fault
- 1. The energizing of a metal water pipe or other metal that should not conduct.
Lesson 23A, Electrical Terms and Basic Electricity - 2. Current in conductive material, such as metal, that is normally not energized.
Lesson 23B, Grounding, Bonding and the Electrical Service - 3. Current on the energized and neutral wires that differs by about 6 milliamperes or more.
Lesson 24B, Overcurrent Protection, GFCI and AFCI - Ground fault circuit interrupter (GFCI)
- Either a breaker or a receptacle that opens the circuit when current in the energized and neutral conductors is unbalanced.
Lesson 23A, Electrical Terms and Basic Electricity - Ground snow load
- An estimate of how much the snow built up on a surface weighs.
Lesson 11A, Structural Scope and Terms - Ground-source heat pump
- A closed-loop heat pump that exchanges heat with the ground, commonly but incorrectly called geothermal.
Lesson 28A, Cooling Systems: Understanding the System - Grounded conductor
- 1. The conductor deliberately connected to earth, often called the neutral.
Lesson 23A, Electrical Terms and Basic Electricity - 2. The utility's neutral wire; the low resistance return path to the source.
Lesson 23B, Grounding, Bonding and the Electrical Service - Grounding
- The intentional earth connection that gives current another path back to its source.
Lesson 23A, Electrical Terms and Basic Electricity - Grounding electrode
- 1. Metal in direct earth contact, such as a ground rod or footing steel, that grounds the electrical system.
Lesson 23A, Electrical Terms and Basic Electricity - 2. The part of the grounding electrode system in contact with the earth, such as a ufer ground, a driven rod or pipe, or metal water service pipe.
Lesson 23B, Grounding, Bonding and the Electrical Service - Grounding electrode conductor
- The conductor that connects the grounding electrodes to the utility's grounded (neutral) wire; most CSST should have a bonding connection to it.
Lesson 38F, Gas Pipe Materials: Black Steel, Copper and CSST - Grounding electrode conductor (GEC)
- 1. The conductor from the grounding electrode to the electrical system, usually connected at the service equipment.
Lesson 23A, Electrical Terms and Basic Electricity - 2. The conductor that connects the grounding electrodes to the utility's grounded (neutral) wire.
Lesson 23B, Grounding, Bonding and the Electrical Service - 3. The conductor that connects the grounding system to the grounding electrode.
Lesson 24C, Panelboard Defects, Subpanels and Problem Panels - Grounding electrode system
- 1. One or more grounding electrodes together with the GEC.
Lesson 23B, Grounding, Bonding and the Electrical Service - 2. The connection between a building's grounding system and the earth.
Lesson 24C, Panelboard Defects, Subpanels and Problem Panels - 3. One or more grounding electrodes together with the grounding electrode conductor.
Lesson 38F, Gas Pipe Materials: Black Steel, Copper and CSST - Grounding system
- The house system that acts like a surge suppressor in some cases, sending voltage surges to ground; it has minimal effect on clearing ground faults.
Lesson 23B, Grounding, Bonding and the Electrical Service - Grounding terminal bar
- The bar where EGCs connect. In a subpanel it is bonded to the enclosure.
Lesson 24C, Panelboard Defects, Subpanels and Problem Panels - Grout (masonry)
- 1. A high-water, fluid-like mortar that fills masonry cores, such as those of CMUs.
Lesson 11A, Structural Scope and Terms - 2. Mortar thinned with extra water so it can be poured into brick and block cores.
Lesson 39A, Fireplace Types and Terms, Firebox, Hearth and Clearances - Guard
- A barrier on an open side of a walking surface that protects against falls; also called a guardrail, balustrade, or banister.
Lesson 18A, Stairs, Ramps, Handrails and Guards - Guard post
- A post that holds up a deck guard.
Lesson 6C, Deck Guards, Framing, Flooring, Bracing, Beams, Footings and Defects - Guardrail
- A guard, or a combined handrail and guard on an open-sided stair.
Lesson 18A, Stairs, Ramps, Handrails and Guards - Gun-type
- The most common oil burner type in houses; also called the atomizing type.
Lesson 32C, Oil Burners - Gusset plate
- A plate fastened across a rafter pair at the ridge where no ridge board or ridge beam is installed.
Lesson 13A, Roof and Ceiling Framing, Rafters, Ties and Purlins - Gusset plates
- 1. Metal plates, pressed on under high pressure, that join truss webs to chords.
Lesson 12B, I-Joists, SCL, Glulam and Floor Trusses - 2. Metal plates that attach truss webs to chords.
Lesson 13B, Roof Framing Defects, Trusses and Attic Access - Gutter
- A horizontal trough at the eaves that collects roof water and carries it to a downspout for discharge away from the foundation.
Lesson 9C, Roof Drainage: Gutters, Scuppers and Internal Drains - Guyed tower
- A wind turbine tower held up by guy cables; less expensive than a self-supporting tower, but it needs more land.
Lesson 27B, Alternative Energy Systems: Solar PV, Wind and Solar Water Heating
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