Home inspection glossary.

A

AFCI

Arc-fault circuit interrupter — a breaker that trips on the electrical signature of an arcing connection, a fire-ignition source.

AFUE

Annual Fuel Utilization Efficiency — gas furnace efficiency as a percentage.

Air handler

The indoor unit of a heat-pump or AC system — blower, coil, and (on a heat pump) the backup heat strips.

Aluminum branch wiring

Single-strand aluminum wire installed roughly 1965–1973. The fire risk is at the connections; CO/ALR devices, COPALUM crimps or a copper rewire are the accepted remedies.

Architectural shingle

Thicker, layered asphalt shingle with a dimensional look. Now the default; roughly 30-year estimated life vs. 20 for 3-tab.

Auxiliary heat

Backup electric heat strips that come on automatically to supplement a heat pump in cold weather. Normal in a cold snap.

B

Backfill

Soil placed back against a foundation after construction. Poorly compacted backfill settles and pulls the grade toward the house.

Baffles

Channels in the attic that keep insulation from blocking the soffit vents.

Balloon framing

Framing where wall studs run the full height of the house from foundation to roof. Common before roughly the 1930s. A fire-spread concern because there is no fire-stop between floors.

Belly (sewer line)

A sag in a buried drain line that holds standing water and collects debris.

Bonding and grounding

Two different things: grounding gives fault current a path to earth; bonding ties metal systems together so they stay at the same potential.

Brick veneer

A single thickness of brick hung on a wood frame with an air gap behind it. A facing, not structural.

C

C rating (C1–C6)

The appraiser's condition scale, separate from quality. C1 is brand new; C6 needs substantial repairs.

Cast-iron drain

Heavy black waste pipe in older homes. Roughly 60 years above ground.

Cleanout

A capped access point in the drain line for clearing clogs.

CMU / concrete block

Concrete masonry unit — the hollow block used for many foundation walls here. Block walls are the ones that bow.

CO/ALR

The rating mark on switches and receptacles approved for use with aluminum wiring.

Condensate line

The drain carrying water away from an air conditioner or high-efficiency furnace. A clogged line backs water up at the air handler.

Condenser

The outdoor unit of an AC or heat-pump system.

Cover-collapse sinkhole

The sudden type: soil above a void gives way all at once. The Kentucky Geological Survey maintains a reporting tool for them.

CPVC

Rigid cream or tan plastic supply pipe, solvent-welded.

Crawlspace

A short accessible space between the soil and the floor framing. Moisture control is everything.

D

Data plate

The manufacturer's label on HVAC equipment, water heaters and manufactured homes. The serial number usually encodes the build date.

Deferred maintenance

Upkeep that should have been done and wasn't. A pattern of it predicts what else was skipped.

Dielectric union

A fitting that separates copper and steel pipe so they do not corrode each other.

Double-tapped breaker

Two conductors under one breaker terminal rated for one. Common, easily corrected, flagged because loose shared terminals heat up.

Drain field / leach field

The buried network of perforated pipe where septic effluent disperses into the soil. The expensive part when it fails.

Drain pan

A shallow pan under a water heater in an attic or over finished space, piped to a drain. Without one, a leak is a flood.

Drip edge

Metal at the roof edge that directs water off the deck and into the gutter.

Dual fuel

A heat pump paired with a gas furnace; the system switches to gas in cold weather instead of running electric strips.

E

Efflorescence

White, chalky mineral deposit left on masonry after water passes through and evaporates. Evidence that water has been moving through the wall.

Egress window

A basement window large enough and low enough for an adult to climb out and a firefighter to climb in. Required for a finished basement bedroom.

EIFS

Exterior Insulation and Finish System — synthetic stucco over foam. Has a documented history of moisture-intrusion problems; always inspect.

Eleven-month warranty inspection

An inspection scheduled before a builder's one-year workmanship warranty expires, with the punch list submitted in writing.

Emergency heat (EM heat)

A manual thermostat setting that shuts the heat pump off entirely and runs on electric strips alone. Only for when the heat pump has failed; expensive to run.

Encapsulation

Sealing a crawlspace completely — heavy liner on floor and walls, sealed vents, often a dehumidifier. The upgrade from a basic vapor barrier.

EPDM (roofing)

Black rubber membrane used on flat and low-slope roofs. Roughly 15 to 25 years.

Expansion tank

A small tank on the water heater supply that absorbs pressure as water heats. Required on closed systems.

Exposed-fastener metal roof

Metal panels screwed straight through the face, with a rubber washer under each screw head sealing the hole. Cheaper than standing seam and requires periodic fastener maintenance.

F

Failed seal

When the seal between the panes of a double-pane window fails, letting moisture in. Fog between the panes is the sign; the unit gets replaced, not repaired.

Fascia

The vertical board at the edge of the roofline that the gutter attaches to.

Fastener back-out

Screws on a screw-down metal roof working loose as the panel expands and contracts against them. Screw heads standing proud of the panel are the sign.

Fastener washer / grommet

The rubber (EPDM or neoprene) sealing washer under an exposed metal-roof screw. Thermal cycling and UV degrade it; it is the first thing to fail on a screw-down metal roof.

Federal Pacific / Zinsco

Panel brands from the 1950s–80s widely reported for breakers that fail to trip. Flagged by most inspectors and many insurers.

Fiber cement siding

Cement-and-fiber board siding (Hardie is the common brand). Durable, fire- and pest-resistant; needs caulk and paint maintenance at joints.

First Hour Rating (FHR)

How much hot water a tank heater can deliver in a busy hour, printed on the yellow EnergyGuide label. The number that actually matters for sizing.

Flashing

Sheet metal that seals the joints where a roof meets something else — a wall, chimney, valley or vent. Most roof leaks are flashing failures.

Foundation certification

An engineer's letter certifying that a manufactured home's foundation meets HUD guidelines. Required for FHA, USDA and HUD lending.

French drain

A gravel-filled trench with a perforated pipe that collects and redirects water away from a foundation.

G

Galvalume

Steel coated with an aluminum-zinc alloy, the common base for metal roofing. Corrodes when in contact with copper or lead.

Galvanic corrosion

Corrosion where two dissimilar metals touch in the presence of moisture — copper flashing on a steel roof, for example.

Galvanized steel pipe

Threaded steel supply pipe in pre-1960s homes. Rusts shut from the inside; low pressure and brown water are the symptoms.

GFCI

Ground-fault circuit interrupter — cuts power when it senses current leaking to ground. Required near water: kitchens, baths, garages, exteriors, crawlspaces.

H

Heat pump

A system that heats and cools by moving heat rather than making it. Loses efficiency in deep cold, so it carries backup electric heat strips.

HSPF / HSPF2

Heating Seasonal Performance Factor — heat-pump heating efficiency. Higher is better.

HUD tag / data plate

The metal certification label and the paper data plate on a manufactured home. Lenders need both; missing ones are a closing problem.

I

Ice and water shield

Self-adhering membrane underlayment applied at eaves, valleys and penetrations where ice dams and leaks start.

ICF

Insulated Concrete Forms — foam forms that stay in place after concrete is poured, making a strong, highly insulated wall.

I-joist

An engineered floor joist shaped like a capital I. Light and strong, but sensitive to improper cutting for ducts or plumbing.

K

Karst

Terrain on water-soluble bedrock, usually limestone, where dissolving rock creates underground voids, sinkholes and springs. Hardin County sits on karst limestone.

Kentucky 811

The free call-before-you-dig service. Required by law before any excavation.

Kick-out flashing

The small angled piece at the bottom of a roof-to-wall intersection that diverts runoff into the gutter instead of into the wall. The classic miss on newer homes.

Knee wall

A short wall under a sloped roof, common in Cape Cods and attic conversions. Frequently under-insulated.

Knob-and-tube

Early wiring (pre-1950) with ceramic knobs and tubes, no ground. An insurability problem before it is a safety problem.

L

Lipstick flip

A rehab that replaced surfaces (paint, flooring, kitchen) but not systems (roof, panel, HVAC, supply lines). Fresh paint in only the crawlspace is the classic tell.

Load-bearing wall

A wall carrying weight from above. Removing one without a properly sized beam is a common finding in 'open concept' conversions of older homes.

Low-E

A microscopically thin coating on window glass that reflects heat. Improves efficiency.

LVL beam

Laminated veneer lumber — an engineered beam made of layered wood veneers. Strong, straight, and not to be cut or notched in the field.

M

Manufactured home

Built entirely in a factory to the federal HUD code on a steel chassis. Financing is harder and value behaves differently. Not the same as modular.

Material defect

A problem with a system or component that has a significant adverse impact on value or poses an unreasonable safety risk. End of service life alone is not a material defect.

Mini-split

A ductless heating and cooling system: an outdoor unit feeding one or more wall-mounted indoor units.

Mitigation (radon)

A system, usually sub-slab depressurization with a fan, that vents radon from under the house. A bounded, negotiable repair item.

Mobile home

A factory-built home from before the HUD code took effect on June 15, 1976. Very hard to finance.

Modular home

Built as sections in a factory to the same local building code as a site-built home, then set on a permanent foundation. Finances and appraises like site-built.

N

Negative grade

Soil sloping toward the foundation instead of away from it. The most common driver of wet basements and crawlspaces.

Nolin RECC

The rural electric cooperative serving much of Hardin County outside town.

O

Oil canning

Visible waviness in the flat areas of metal roof or siding panels. Cosmetic, and normal on wide flat panels.

Orangeburg pipe

Tar-impregnated fiber drain pipe used mid-century. Deforms and collapses; replace on sight.

OSB

Oriented strand board — engineered structural panel made from wood strands and resin. Standard sheathing and subfloor material.

Owned vs. leased propane tank

A leased tank belongs to the supplier and transfers differently at closing. Ask which it is.

P

Packaged unit

Heating and cooling in one cabinet outside or on the roof. Common on manufactured homes and some slab builds.

pCi/L

Picocuries per liter — the unit radon is measured in.

Permanent foundation (manufactured)

A foundation meeting HUD guidelines for a manufactured home. FHA, USDA and HUD lending require an engineer's certification that it qualifies.

PEX

Cross-linked polyethylene — flexible red/blue supply tubing with crimp fittings. Standard in new construction.

Pier and beam

A foundation of piers or columns with beams spanning between them.

Pipe boot

The rubber or metal collar that seals a plumbing vent where it passes through the roof. A cracked boot is one of the most common roof leaks.

Platform framing

The modern standard: each floor is built as its own platform and the walls for the next floor stand on it. Fire-stops between floors come built in.

Polybutylene (PB)

Grey flexible supply piping installed roughly 1978 to mid-1995, usually stamped PB2110. Fails without warning; affects insurability.

Post and beam / timber frame

Heavy vertical posts and horizontal beams carry the loads, allowing open interiors. Log and timber-frame homes appraise and insure differently.

Pre-drywall inspection

An inspection of a new build while framing, wiring, plumbing and flashing are still exposed. The only chance to see the bones.

Private well

A drilled well serving one home. Ask about depth, flow rate, pump age and the last water test; government-backed loans generally require one.

Punch list

The written list of defects submitted to a builder for correction.

Purlin

A horizontal framing member that runs across rafters or trusses and that metal roof panels are often screwed to. On an exposed-fastener roof, leaks line up along the purlins.

Q

Q rating (Q1–Q6)

The appraiser's quality-of-construction scale. Q4 is standard builder grade; Q6 has deficiencies that must be repaired before a loan can be delivered.

R

Radon

A naturally occurring radioactive gas that enters homes from the soil. EPA action level is 4.0 pCi/L; Hardin County is EPA Zone 2.

Reversed polarity

Hot and neutral wires swapped at a receptacle. A shock hazard and a simple fix.

Ridge vent

A continuous vent along the roof peak that exhausts attic air. Works with soffit vents to move air through the attic.

Roof truss

A factory-built triangulated roof frame. Never cut, drilled or modified without an engineer — a cut truss is a structural finding.

S

SEER / SEER2

Seasonal Energy Efficiency Ratio — cooling efficiency. SEER2 is the newer test standard; the two are not directly comparable.

Septic system

A tank plus a drain field for homes without city sewer. Needs a separate inspection; ask for permit and pumping records.

Service panel

The main breaker box. Estimated life around 60 years; flagged for what is inside it and its era.

Service size

The amperage of the main electrical service — 100 amps was standard for decades; 200 is modern. A house that added central air and an electric range on 100 amps is at its limit.

Sewer scope

A camera run down the main drain line to find roots, bellies, and collapsed pipe. Cheap insurance on any older home or one with mature trees.

Sheathing

The panels fastened to the outside of the framing, under the siding. Structural plywood or OSB adds shear strength; thin foam or fiberboard sheathing does not.

Short cycling

A system that starts and stops rapidly instead of running full cycles. A red flag for sizing, refrigerant or control problems.

Sinkhole

A surface depression or collapse where the ground above an underground void gives way. Standard homeowner policies often exclude sinkhole damage.

SIPs

Structural Insulated Panels — foam core sandwiched between structural boards, used for walls and roofs.

Sistered joist

A second joist fastened alongside an original one to reinforce or repair it. Legitimate when done correctly.

Slab on grade

A single poured concrete slab with no space beneath it. Plumbing runs in or under the slab.

Snow guards

Small brackets on a metal roof that keep snow from sliding off in a sheet. A safety item above entries and gas meters.

Soffit

The underside of the roof overhang. Soffit vents let air into the attic.

Spalling

Concrete or brick flaking and breaking away at the surface, usually from freeze-thaw cycles or corroding steel inside.

Standing seam

Metal roofing with raised vertical seams and concealed clip fasteners. No screws through the panel face; panels can expand and contract freely.

Step flashing

Overlapping L-shaped pieces of metal woven into the shingles where a roof meets a vertical wall.

Stick-built

Framed piece by piece on site. The most common construction type and the value benchmark everything else is measured against.

Subfloor

The structural floor deck (plywood or OSB) under the finish flooring. A soft or bouncy spot under new flooring is a tell.

Sump pump

A pump in a pit at the low point of a basement or crawl that ejects groundwater. Test it; check for a working float and a discharge line that runs well away from the house.

T

Temperature rise

How far a tankless heater must heat the incoming water. Cold winter groundwater means less output from the same unit.

T&P valve

Temperature and pressure relief valve on a water heater. Its discharge pipe must run down to near the floor at full diameter; a missing or wrong pipe is a serious finding.

TPO

White single-ply membrane used on flat roofs. Roughly 7 to 20 years.

U

Underlayment

The water-resistant layer between the roof deck and the shingles or panels. Synthetic underlayment or ice-and-water shield are the modern versions of tar paper.

V

Vapor barrier

Plastic sheeting laid over crawlspace soil to keep ground moisture out of the framing above.

W

Walkout / daylight basement

A basement with a grade-level door on one side (walkout) or above-grade windows on one side (daylight).

WDO / termite inspection

Wood-destroying organism inspection, commonly required on VA and FHA financed purchases.

Weep holes

Small gaps left in the bottom course of brick veneer so water behind the brick can drain out. Must be open.