Glossary, 80 terms
Home inspection terms: H
Each definition is the Key Term from the lesson named under it. Where two lessons define a term for different uses, both are here.
- H-clip
- A metal clip that gives edge support between plywood or OSB roof sheathing panels.
Lesson 13A, Roof and Ceiling Framing, Rafters, Ties and Purlins - Habitability
- As the seventh edition of Black's Law Dictionary defines it, a building condition in which the people living there are spared serious defects that might endanger their safety and health.
Lesson 19C, Deficient Conditions, Service Life and Imminent Threats - Habitable space
- A space the heat source should be capable of holding at no less than 68 degrees F; bathrooms, closets, and laundry rooms are not habitable spaces.
Lesson 30, Heating Fundamentals, Combustion and Capacity - Half-round gutter
- One of the two most common gutter styles.
Lesson 9C, Roof Drainage: Gutters, Scuppers and Internal Drains - Handle tie
- 1. An approved device joining the breakers of a multiwire branch circuit so both hot legs disconnect together.
Lesson 23B, Grounding, Bonding and the Electrical Service - 2. A connector joining two breaker handles so the pair protects one 240 volt circuit.
Lesson 24B, Overcurrent Protection, GFCI and AFCI - 3. An approved device that joins two breaker handles so both conductors of a circuit disconnect together.
Lesson 24C, Panelboard Defects, Subpanels and Problem Panels - Handrails
- Rails on a stairway that people grasp for support.
Lesson 18A, Stairs, Ramps, Handrails and Guards - Hanging rod storage area
- The clothes closet space below 6 feet or the highest rod, whichever is higher, reaching 2 feet out from the side and back walls.
Lesson 26B, Switches, Lights and Ceiling Fans - Hard water
- 1. Water carrying dissolved minerals such as calcium and magnesium.
Lesson 35F, Water Treatment Devices and Hot Water Circulation - 2. Water carrying dissolved calcium, magnesium, and other minerals; the most common objection to well water.
Lesson 35H, Cisterns, Water Quality and Fire Sprinklers - Hardboard siding
- Composite wood siding about 7/16 inch thick, some of it made with wood byproducts and binders.
Lesson 4B, Fiber Cement, Hardboard, Insulbrick, Stucco, EIFS, Vinyl, Wood and Wood Structural Panel Siding - Hardwired equipment
- EVSE permanently wired to its branch circuit, with no plug and receptacle.
Lesson 27C, Electric Vehicle Service Equipment (Supplement) - Hardwood
- A name often used for wood floor covering.
Lesson 17B, Interior Doors and Floor Coverings - Hartford Loop
- A piping configuration from 1919 that raises the point where the wet return meets the equalizer pipe to 2 to 4 inches beneath the normal boiler water level.
Lesson 33C, Steam Heating Systems and Distribution Piping - Head jamb
- The top member of a window or door frame.
Lesson 5B, Windows, Window Flashing, Glazing, Window Wells, Escape Openings and Fall Protection - Head joint
- A vertical mortar joint in brick or stone veneer.
Lesson 4A, Exterior Scope and Terms, Adhered Masonry Veneer, Metal and Asbestos Cement Siding and Brick Veneer - Head lap
- 1. The overlap of a tile onto the tile in the course below, typically 3 inches.
Lesson 8A, Steep Slope Roofing: Asphalt Shingles and Tile - 2. The distance one course overlaps the course below it.
Lesson 8C, Steep Slope Roofing: Slate, Polymer, Wood and Ice Dams - Head-and-shoulders inspection
- A limited inspection made from the access opening without entering the attic or crawl space.
Lesson 19D, System Descriptions and Inspection Methods - Header
- 1. The top member of a door frame, or the framing member over a rough opening.
Lesson 5A, Exterior Doors and Safety Glazing at Doors - 2. A beam spanning a door, window, or other wall opening.
Lesson 11A, Structural Scope and Terms - 3. The framing over a door or window opening that spreads the load above around it.
Lesson 12D, Wood Wall Framing, Bracing and Wall Defects - 4. The top member of a door frame.
Lesson 17B, Interior Doors and Floor Coverings - Header flashing
- 1. Flashing across the top of a door or window.
Lesson 4C, Exterior Trim, Flashing and Sealants, Eaves and Cornice - 2. Flashing across the top of a window opening.
Lesson 5B, Windows, Window Flashing, Glazing, Window Wells, Escape Openings and Fall Protection - Header joists
- Joists installed between the trimmer joists at the end of a floor opening.
Lesson 12A, Floor Framing, Spans, Bearing, Notching and Boring - Headwall
- A vertical wall that a roof rises to meet.
Lesson 10A, Roof Flashing: Penetrations, Sidewalls and Headwalls - Hearth
- The fireplace floor on which the fire burns.
Lesson 39A, Fireplace Types and Terms, Firebox, Hearth and Clearances - Hearth extension
- 1. The noncombustible area in front of and beside a fireplace opening where escaping embers can land.
Lesson 39A, Fireplace Types and Terms, Firebox, Hearth and Clearances - 2. The area in front of and to each side of the firebox opening, with a noncombustible finish over noncombustible insulation.
Lesson 40A, Factory-Built Fireplaces and Chimneys - Heat distribution method
- A way to classify heating systems by how they deliver heat: forced-air, gravity, hydronic, or radiant.
Lesson 31A, Gas Appliance Categories and Gas Forced-Air Furnaces - Heat exchanger
- The furnace component heated inside by the gas fire, with house air passing over its exterior and combustion gasses kept within it.
Lesson 31A, Gas Appliance Categories and Gas Forced-Air Furnaces - Heat exchanger (boiler)
- The part of a boiler where moving water is heated until it turns to steam.
Lesson 33E, Steam Boiler Components, Solid Fuel and Related Components - Heat exchanger (HRV or ERV)
- The core where the incoming and outgoing air streams cross and trade heat.
Lesson 16A, Mechanical Ventilation, HRV and ERV, Whole-House Fans - Heat pump
- A system that heats a house by moving outdoor heat inside and cools it by removing indoor heat.
Lesson 28A, Cooling Systems: Understanding the System - Heat recovery ventilation (HRV)
- A designed and controlled ventilation system whose exhaust components are not in scope for condition or adequacy.
Lesson 14A, Insulation Scope and Terms, R-Value and How Insulation Works - Heat Recovery Ventilation System (HRV)
- A whole house ventilation unit that transfers only heat between incoming and outgoing air.
Lesson 16A, Mechanical Ventilation, HRV and ERV, Whole-House Fans - Heat strip
- A heating strip installed at the eaves to try to prevent ice dams.
Lesson 8C, Steep Slope Roofing: Slate, Polymer, Wood and Ice Dams - Heat strips
- Heating elements installed in the field in a heat pump air handler; also called backup, emergency, or auxiliary heat, and duct heaters.
Lesson 33A, Electric Heating Systems - Heating degree days
- A measure of winter temperature that is the basis of the eight climate zones.
Lesson 14B, Vapor Retarders and the House as a System - Heel
- The inlet on top of a quarter bend, made as low-heel or high-heel.
Lesson 37B, DWV Fittings, Cleanouts and Defects - Helical pier
- A pier like one large screw with a single thread, used to raise and stabilize settled footings.
Lesson 11D, Foundation Repairs, Crawl Spaces and Slabs - Hermetic seal
- 1. The seal that closes the space between the panes of a multiple pane window.
Lesson 5B, Windows, Window Flashing, Glazing, Window Wells, Escape Openings and Fall Protection - 2. The airtight seal between layers of glazing.
Lesson 10B, Skylights - High limit control
- The aquastat control that operates while the thermostat calls for heat.
Lesson 33B, Hot Water Heating Systems - High limit sensor
- 1. A sensor, also called a fan limit sensor, that shuts off the furnace when it detects excess heat.
Lesson 31A, Gas Appliance Categories and Gas Forced-Air Furnaces - 2. A sensor that shuts the gas valve off if the water exceeds a set temperature.
Lesson 36B, Electric and Gas Storage Tank Water Heaters - High limit sensor (fan limit sensor)
- The one safety sensor in an electric furnace, which shuts the furnace off when it detects excess heat.
Lesson 33A, Electric Heating Systems - High loop
- A dishwasher drain tube fastened as high as it will go in the sink base cabinet, to prevent backflow.
Lesson 41A, Appliance Scope and Terms, Cooktops, Ranges, Ovens and Dishwashers - High pressure system
- A steam system operating above 15 psig.
Lesson 33C, Steam Heating Systems and Distribution Piping - High pressure, high velocity duct
- Small flexible metallic duct, about 2 to 3 inches in diameter, carrying air faster than 2,000 feet per minute.
Lesson 29, Air Distribution Systems, Ducts, Returns and Filters - High velocity ducts
- The smaller ducts of a few central systems, which are uncommon.
Lesson 28A, Cooling Systems: Understanding the System - High-efficacy bulb
- An energy efficient bulb, such as a CFL, LED, or fluorescent bulb.
Lesson 26B, Switches, Lights and Ceiling Fans - High-speed (broadband) connection
- An internet connection usually defined as 25 megabits per second or more of download speed.
Lesson 18B, Cabinets, Countertops and Smart Home Scope - Hinge jamb
- 1. The side of a door frame that carries the hinges.
Lesson 5A, Exterior Doors and Safety Glazing at Doors - 2. The side of a door frame where the hinges are mounted.
Lesson 17B, Interior Doors and Floor Coverings - Hinge plate
- 1. One of the two hinge leaves, one on the door and one on the jamb, joined by a pin.
Lesson 5A, Exterior Doors and Safety Glazing at Doors - 2. One of two plates, one on the door and one on the frame jamb, joined by the pin the door swings on.
Lesson 17B, Interior Doors and Floor Coverings - Hinged exterior door
- An exterior door that swings on three or four hinges mounted at its side.
Lesson 5A, Exterior Doors and Safety Glazing at Doors - Hinged swinging door
- A door that swings on two or three hinges mounted on its side.
Lesson 17B, Interior Doors and Floor Coverings - Hip jack rafter
- A shortened rafter framed from a hip rafter to the wall.
Lesson 13A, Roof and Ceiling Framing, Rafters, Ties and Purlins - Hip roof
- A roof style of four roof sections joined at the ridge.
Lesson 13A, Roof and Ceiling Framing, Rafters, Ties and Purlins - Hold-down anchor
- A metal connector on a deck joist, to which a guard post is bolted.
Lesson 6C, Deck Guards, Framing, Flooring, Bracing, Beams, Footings and Defects - Holes
- Visible or microscopic openings through which air and water vapor pass.
Lesson 14B, Vapor Retarders and the House as a System - Hollow core door
- A door that is solid only at its perimeter.
Lesson 17B, Interior Doors and Floor Coverings - Home inspection
- The observation of systems and components on, in, and around a property, to report their condition when inspected.
Lesson 19A, Inspection Scope, Limitations, Standards and Report Formats - Honeycombing
- An area of a concrete wall with less concrete than the rest; also called a void or an aggregate pocket.
Lesson 11C, Basement Foundations, Materials, Waterproofing and Defects - Hood (kitchen exhaust)
- An enclosure above the cooktop that holds a kitchen exhaust fan.
Lesson 16B, Dryer, Kitchen and Bathroom Exhaust - Hopper
- The bin at the top or rear of a pellet stove that receives the pellets.
Lesson 40B, Draft Problems, Fireplace Inserts, Wood and Pellet Stoves - Hopper window
- An operable window hinged at the bottom, with a sash that swings in.
Lesson 5B, Windows, Window Flashing, Glazing, Window Wells, Escape Openings and Fall Protection - Horizontal guard components
- Horizontal parts, such as cables and decorative metal, that fill a deck guard.
Lesson 6C, Deck Guards, Framing, Flooring, Bracing, Beams, Footings and Defects - Horizontal system
- A ground-source loop laid in trenches, which can need a large amount of land.
Lesson 28A, Cooling Systems: Understanding the System - Hose bibb
- A faucet for connecting a garden hose, also spelled bib and also called a hose cock, spigot, or sill cock.
Lesson 34D, Faucets, Shower Valves, Hose Bibbs and Aerators - Hose bibb (bib)
- A supply fixture for attaching a garden hose; also called a spigot.
Lesson 34A, Plumbing Scope and Plumbing Terms - Hose connection vacuum breaker
- A backflow preventer on or built into a hose bibb that releases water through bottom holes during backsiphonage.
Lesson 35E, Standpipes, Floor Drains and Backflow Prevention - Hot water circulation pump
- A pump that keeps hot water moving through the pipes so it is on hand nearly instantly.
Lesson 35F, Water Treatment Devices and Hot Water Circulation - House wrap
- A sheet WRB, usually lapped the same way as #15 felt and Grade D paper.
Lesson 15A, Insulation Defects, Water-Resistive Barriers, Radiant Barriers and Fenestration - HSPF (heat seasonal performance factor)
- Heat pump efficiency in heating mode, the heating season output divided by the electric energy used, about 7 to 10.
Lesson 28A, Cooling Systems: Understanding the System - Hub
- An enlarged section formed at one end of a cast iron pipe; called a bell on clay pipe.
Lesson 37A, DWV Rules and Pipe Materials - Hub (bell)
- The enlarged end of a fitting or pipe, into which another pipe is inserted.
Lesson 34A, Plumbing Scope and Plumbing Terms - Hubless
- Cast iron pipe made without a hub and spigot, joined with a banded coupling.
Lesson 37A, DWV Rules and Pipe Materials - Humidifier
- A device that adds moisture to a forced-air heating system.
Lesson 33E, Steam Boiler Components, Solid Fuel and Related Components - HVAC
- Abbreviation for heating, ventilation, and air conditioning.
Lesson 28A, Cooling Systems: Understanding the System - Hybrid heat pump
- A heat pump system combining technologies such as air-source and ground-source; very uncommon in houses.
Lesson 28A, Cooling Systems: Understanding the System - Hybrid report
- A report format that mixes checklist and narrative components.
Lesson 19A, Inspection Scope, Limitations, Standards and Report Formats - Hybrid stucco
- A name sometimes used for proprietary cement stucco systems sold as one-coat or two-coat.
Lesson 4B, Fiber Cement, Hardboard, Insulbrick, Stucco, EIFS, Vinyl, Wood and Wood Structural Panel Siding - Hybrid water heater
- A heat pump water heater that also has electric resistance heating elements for periods of high demand.
Lesson 36C, Demand, Oil and Heat Pump Water Heaters, Relief Valves and Drain Pans - Hydrogen sulfide
- The cause of a rotten egg taste and smell in some water.
Lesson 35H, Cisterns, Water Quality and Fire Sprinklers - Hydronic distribution
- A heat distribution method that moves heat with heated liquid or steam in pipes, mostly by radiation and convection.
Lesson 31A, Gas Appliance Categories and Gas Forced-Air Furnaces - Hydronic heating
- A system that heats by moving steam or hot liquid through pipes.
Lesson 30, Heating Fundamentals, Combustion and Capacity - Hydrostatic pressure
- 1. The pressure of water in the soil, which can push laterally on foundation walls.
Lesson 11B, Forces and Soils, Footings, Piers and Columns - 2. Water pressure.
Lesson 11C, Basement Foundations, Materials, Waterproofing and Defects - Hygroscopic
- 1. Absorbing water.
Lesson 11C, Basement Foundations, Materials, Waterproofing and Defects - 2. Tending to absorb water, as CMUs and structural bricks usually do.
Lesson 12E, CMU, Brick, ICF, SIPs and Uncommon Wall Materials
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