Glossary, 47 terms
Home inspection terms: I
Each definition is the Key Term from the lesson named under it. Where two lessons define a term for different uses, both are here.
- I-joist (wood)
- An engineered wood joist with an OSB or plywood web set into grooved wood flanges; sometimes called an I-beam.
Lesson 12B, I-Joists, SCL, Glulam and Floor Trusses - Ice barrier underlayment
- 1. Underlayment specified in cold climates where local authorities require it.
Lesson 8A, Steep Slope Roofing: Asphalt Shingles and Tile - 2. An underlayment layer called for in cold climates when the local authority requires it.
Lesson 8B, Steep Slope Roofing: Fiber Cement and Metal - 3. An impervious underlayment at the eaves, often peel and stick flashing.
Lesson 8C, Steep Slope Roofing: Slate, Polymer, Wood and Ice Dams - Ice dam
- A block of ice at cold eaves, built from snow melted by house heat, that can back water under the roof covering.
Lesson 8C, Steep Slope Roofing: Slate, Polymer, Wood and Ice Dams - IFTTT (if this, then that)
- A technology that controls some smart devices with applets, which perform an action when a condition occurs.
Lesson 18B, Cabinets, Countertops and Smart Home Scope - Igniter
- A component that glows hot to light the gas, usual in newer furnaces.
Lesson 31A, Gas Appliance Categories and Gas Forced-Air Furnaces - Ignition barrier
- A covering over foam plastic insulation that protects less than a thermal barrier.
Lesson 12C, Wall Systems, Fireblocking and Fire Separation - Ignition source
- The point of an appliance to which the 18 inch elevation above a garage floor is measured.
Lesson 36D, Water Heater Installation, Seismic Bracing, Thermal Expansion and Defects - Ignition transformer
- The component that supplies the high voltage arc used to light the oil and air mixture.
Lesson 32C, Oil Burners - Imminent threat
- A situation that threatens occupant health and safety, or threatens property damage, right away.
Lesson 19C, Deficient Conditions, Service Life and Imminent Threats - Implication statement
- The part of a deficiency statement that explains why a deficiency matters or what could result if it is not addressed.
Lesson 19B, Deficiency Statements and Recommendations - Incorporated by reference
- Made part of a contract by being named in it, with the same force as text printed in full there.
Lesson 21B, Contracts and Insurance - Indemnification clause
- A contract clause under which the client defends the home inspector in suits by third parties and pays any judgments from them.
Lesson 21B, Contracts and Insurance - Indirect system
- A solar water heating system that heats a non-freezing transfer fluid, which passes its heat to the water through a heat exchanger.
Lesson 27B, Alternative Energy Systems: Solar PV, Wind and Solar Water Heating - Indirect-fired water heater
- 1. A domestic hot water method with a finned copper coil, heated by boiler water, inside a separate water tank.
Lesson 33B, Hot Water Heating Systems - 2. A water heater whose finned copper coil, heated by boiler water, sits in a tank of its own.
Lesson 33C, Steam Heating Systems and Distribution Piping - Individual branch circuit
- A branch circuit that supplies one piece of equipment only.
Lesson 27C, Electric Vehicle Service Equipment (Supplement) - Individual vent
- A vent system for one fixture of any type.
Lesson 38C, Vent Systems, Vent Connections and Air Admittance Valves - Induced draft furnace
- The most common Category I gas furnace, medium efficiency at about 80 percent, with inshot burners.
Lesson 31A, Gas Appliance Categories and Gas Forced-Air Furnaces - Infrared camera
- An instrument that measures surface infrared radiation and shows it as an image whose colors correspond to temperature.
Lesson 20, Inspection Tools and the Inspection Process - Infrared thermometer (laser thermometer)
- An instrument that measures surface infrared radiation and displays an average temperature across an area.
Lesson 20, Inspection Tools and the Inspection Process - Inlet
- The opening where water enters a trap.
Lesson 38A, Traps and Fixture Drains - Insert
- A vented decorative gas or oil appliance for installation into a masonry fireplace.
Lesson 31B, Floor and Wall Furnaces, Room Heaters and Unvented Appliances - Inshot burner
- A burner that draws gas into the heat exchanger through a single opening.
Lesson 31A, Gas Appliance Categories and Gas Forced-Air Furnaces - Inspection tool
- A tool used routinely, where nothing observed suggests a problem.
Lesson 20, Inspection Tools and the Inspection Process - Installed
- For a cabinet, permanently attached, so that removal requires tools.
Lesson 18B, Cabinets, Countertops and Smart Home Scope - Insulated tube collector (evacuated tube)
- A collector of finned glass tubes, each inside an air-sealed outer tube.
Lesson 27B, Alternative Energy Systems: Solar PV, Wind and Solar Water Heating - Insulating concrete forms
- 1. Concrete wall forms with built-in insulation that stay in place after the pour.
Lesson 11C, Basement Foundations, Materials, Waterproofing and Defects - 2. Proprietary forms of a material such as polystyrene that are filled with reinforcing steel and concrete and remain in the wall.
Lesson 12E, CMU, Brick, ICF, SIPs and Uncommon Wall Materials - Insulating concrete forms (ICF)
- A proprietary wall system of forms, made of a material such as polystyrene, that are filled with concrete and remain in place.
Lesson 12C, Wall Systems, Fireblocking and Fire Separation - Insulation contact (IC) rated
- A recessed light rating that allows insulation to cover the light.
Lesson 26B, Switches, Lights and Ceiling Fans - Insulation shield
- 1. A barrier around an appliance vent or metal chimney that keeps insulation away from it.
Lesson 15A, Insulation Defects, Water-Resistive Barriers, Radiant Barriers and Fenestration - 2. A shield that should be installed where a metal chimney runs through an insulated area.
Lesson 40A, Factory-Built Fireplaces and Chimneys - Insulbrick siding
- Asphalt impregnated fiberboard embossed to look like brick; other names are Insulstone and Insulwood.
Lesson 4B, Fiber Cement, Hardboard, Insulbrick, Stucco, EIFS, Vinyl, Wood and Wood Structural Panel Siding - Integrated gutter (Yankee gutter)
- A gutter built into the eaves, with a lining of EPDM, metal, or another roof covering.
Lesson 9C, Roof Drainage: Gutters, Scuppers and Internal Drains - Interconnection
- 1. The linking of every smoke alarm to the others, by wire or wireless, so that all of them sound when one activates.
Lesson 27A, Smoke and Carbon Monoxide Alarms, Load Controllers and Generators - 2. The hard wired or wireless linking of alarms so that all sound when one activates.
Lesson 42, Life Safety Systems: Egress, Fire Separation, Alarms and Sprinklers - Interdependent system
- The house, its occupants, and its environment, which constantly act on each other.
Lesson 14B, Vapor Retarders and the House as a System - Interface wiring
- The wiring from a service provider connected by wire to the wireless router, the house communication hub.
Lesson 18B, Cabinets, Countertops and Smart Home Scope - Interlayment
- Felt laid between courses of wood shakes.
Lesson 8C, Steep Slope Roofing: Slate, Polymer, Wood and Ice Dams - Intermediate metal conduit (IMC)
- A round metal pipe with a thinner wall and lighter weight than RMC.
Lesson 25A, Wiring Methods, Cables and Raceways - Internal drain pipe
- A pipe that carries water from an opening in a low slope roof to the outside of the building.
Lesson 9C, Roof Drainage: Gutters, Scuppers and Internal Drains - Interrogatories
- One party's written questions, which the other party answers in writing.
Lesson 21A, Business Law, Claims and Liability - Interstitial space
- The space between floors.
Lesson 14B, Vapor Retarders and the House as a System - Intumescent coating
- A coating often used as the ignition barrier on foam plastic insulation.
Lesson 12C, Wall Systems, Fireblocking and Fire Separation - Inverted bucket trap
- One of two traps that may serve as the main vent; the other is the ball float trap.
Lesson 33D, Steam Distribution Components, Vents and Traps - Inverter
- The device that converts direct current to alternating current.
Lesson 27B, Alternative Energy Systems: Solar PV, Wind and Solar Water Heating - Ionization alarm
- 1. The most common smoke alarm type, in which smoke disrupts a flow of electricity between two sensors across air ionized by radioactive material.
Lesson 27A, Smoke and Carbon Monoxide Alarms, Load Controllers and Generators - 2. The most common smoke alarm type, in which radioactive material ionizes the space between two sensors.
Lesson 42, Life Safety Systems: Egress, Fire Separation, Alarms and Sprinklers - IRC
- International Residential Code; it governs gas piping after the point of delivery.
Lesson 38F, Gas Pipe Materials: Black Steel, Copper and CSST - Island fixture vent
- A venting method that, like the AAV, is an alternative to a vent run to the exterior.
Lesson 38B, Plumbing Vents: Purpose, Inspection, Terminals and Size - Island fixture vent (loop vent)
- A vent system for sinks only, with a loop of pipe rising above the highest sink outlet.
Lesson 38C, Vent Systems, Vent Connections and Air Admittance Valves - Isolation joint
- A joint between concrete and an adjacent material or structure that lets each move at its own rate.
Lesson 3, Driveways, Walkways, Patios and Pool/Spa Barriers
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