National Home Inspector Exam (NHIE) Concept Review

Overview

This chapter covers what an inspector checks while walking around the outside of the house: the ground around it, paths and driveways, decks and steps, the wall coverings, and the windows and doors. Most of these items have one job in common, which is keeping water away from the house and keeping people from getting hurt.

Water is the main enemy. The ground next to the foundation should slope away so rain runs off instead of soaking down along the walls. Under common model codes the ground typically drops at least 6 inches within the first 10 feet. Siding and wood trim should stay well above the soil, and flashing must lap over the material below it so water is led outward, not behind the wall.

Decks fail in a few predictable places. The ledger board that ties the deck to the house must be bolted or lag-screwed and flashed, never held up by nails alone. Guards are typically required once the deck surface is more than 30 inches above the ground, and stairs need even steps and a usable handrail.

Overview

This chapter is about the roof covering, the flashing that seals its edges and openings, and the gutters that carry water away. The inspector's job is to describe the covering, look for wear and damage, and point out places where water is likely to get in.

Asphalt shingles are the most common covering. As they age they lose their granules, curl or cup at the edges, crack, and blister. Under common model codes they are typically not used on slopes below 2 in 12, and slopes from 2 in 12 up to 4 in 12 need extra underlayment. Missing or lifted shingles after wind should always be noted.

Most leaks start at flashing, not in the middle of the roof. Look closely where the roof meets a wall, at chimneys, in valleys, and around vent pipes. Gutters should be clean and sloped to downspouts, and downspouts should drop water well away from the foundation.

Overview

This chapter covers the parts that hold the house up: footings, foundation walls, posts, beams, joists, and the crawlspace or basement around them. The inspector looks for signs that the structure has moved or is being damaged by water, and explains how serious those signs appear to be.

Cracks tell a story by their shape. Thin vertical cracks in poured concrete are often from normal shrinkage. Stair-step cracks in block or brick suggest settling, and horizontal cracks in a block wall can mean soil pressure is pushing the wall inward. Wide cracks, cracks that are offset, or walls that lean deserve a referral to a structural engineer.

Framing members can be weakened by careless cuts. Under common model codes, notches and holes in joists are limited in size and location. Moisture is the other big threat: look for efflorescence on masonry, water stains, wood rot, and poor crawlspace ventilation.

Overview

This chapter follows electricity from the utility wires to the outlets. It covers the service entrance, the main panel, branch circuits, grounding and bonding, and the special protective devices called GFCIs and AFCIs. Electrical findings are often safety items, so clear reporting matters.

Overhead service wires need enough clearance so people cannot touch them. Under the National Electrical Code they are typically at least 10 feet above finished grade and walkways. At the panel, the inspector checks for proper working space, matching wire and breaker sizes, double-tapped breakers, scorching, and missing covers or knockouts.

Wire size must match the breaker. In common practice, 14-gauge copper is protected at 15 amps, 12-gauge at 20 amps, and 10-gauge at 30 amps. GFCIs protect people from shock in wet areas, while AFCIs reduce fire risk from arcing in living areas. Test them where safe and note any that do not trip.

Overview

This chapter covers the equipment that heats and cools the house: furnaces, boilers, heat pumps, and central air conditioners, along with their venting and ducts. The inspector operates the system with normal controls, looks at what is visible, and reports conditions that affect safety or comfort.

Fuel-burning equipment needs enough air to burn cleanly and a vent that carries exhaust gases outside. Under common model codes, a natural-draft vent connector typically rises at least 1/4 inch per foot toward the chimney, and single-wall metal connectors are kept about 6 inches from combustibles. Backdrafting, rust, scorching near the burner, or a flame that jumps when the blower starts can point to a cracked heat exchanger and carbon monoxide risk.

Air conditioners and heat pumps move heat using refrigerant. In cooling mode, the larger, insulated line is the cool suction line and the smaller line is the warm liquid line. Cooling makes water, so condensate must drain properly, and units above finished space typically need a secondary drain or a pan with a shutoff switch.

Overview

This chapter covers the water that comes into the house and the water that leaves it. It includes supply piping, the drain-waste-vent system, water heaters, and fixtures. The inspector runs water, checks for leaks and poor drainage, and looks for missing safety parts.

Every fixture drain has a trap, a bend that stays filled with water so sewer gas cannot come up into the room. Under common model codes the water seal is typically 2 to 4 inches deep. The trap arm runs from the trap to the vent and slopes slightly downhill, typically 1/4 inch per foot for small pipes. The vent lets air into the system so draining water does not siphon the trap dry. S-traps are not allowed because they tend to siphon.

The water heater must have a temperature and pressure relief valve. Its discharge pipe should be full size, run downhill, have no valve or threads at the end, and typically end no more than 6 inches above the floor or at an approved location. Supply pipe material matters too: polybutylene and old galvanized steel are known for failures.

Overview

This chapter covers the inside of the house and the attic above it. It includes walls, floors, ceilings, stairs, windows and doors, insulation and ventilation, fireplaces, and built-in appliances. Many items here are about comfort, but some, like stairs, alarms, and fireplaces, are about safety.

In the attic, look at how much insulation there is, whether it is spread evenly, and whether air can move through. Under common model codes, attic vent area is typically 1 square foot for every 150 square feet of attic floor, or 1 per 300 when vents are balanced high and low. Bath fans and dryer vents must go outside, not into the attic.

Fireplaces need a solid hearth extension in front and to the sides, and the chimney must be tall enough to draw well. Smoke alarms belong in each bedroom, outside sleeping areas, and on every level, and carbon monoxide alarms are typically needed when the home has fuel-burning appliances or an attached garage.

Overview

This chapter is about turning what you saw into a report the client can understand and act on. A good finding does three things: it describes what was observed, explains why it matters, and recommends a next step. The report is the product the client pays for, so clarity matters as much as accuracy.

Not every defect is equal. Safety issues and major defects that could be costly come first, while routine maintenance items come after. Inspectors are generalists, so when a problem needs deeper evaluation, the right recommendation is to have a qualified specialist look at it rather than guessing the repair.

Use plain words and specific locations. Say what you saw, not what you assume, and avoid vague phrases that leave the client unsure. State any areas you could not inspect and why, such as a locked door, stored items, or unsafe access.

Overview

This chapter covers how a home inspector should conduct business: what the inspection includes and excludes, how to avoid conflicts of interest, and how to set expectations with a written agreement. These topics protect both the client and the inspector.

A home inspection is a visual, non-invasive look at readily accessible systems and components on the day of the inspection. Under typical standards of practice, the inspector does not move furniture, take things apart, or enter areas that are unsafe. It is also not a code compliance inspection and does not guarantee future performance.

Inspectors work for their clients, not for agents or sellers. They should not take fees from contractors for referrals, should disclose any relationships that could affect their judgment, and should not offer to repair things they found during the inspection. A written pre-inspection agreement explains the scope, limits, and fee before the work begins, and the report is shared only with the client's permission.