Technical Knowledge of Home Systems and Components
Systems You Must Know
Technical questions test your understanding of how home systems work and how they fail. For structure, know foundation types, framing, and signs of movement such as cracks, deflection, and rot. For exterior and roofing, know cladding, flashings, drainage, and roof covering materials and their typical defects. For plumbing, know supply and drain materials, water heaters, fixtures, and signs of leaks. For electrical, know service equipment, grounding, bonding, conductors, and common hazards such as double-tapped breakers and missing covers. For HVAC, know heating and cooling equipment, distribution, and combustion safety. For insulation and ventilation, know attic and crawlspace conditions and moisture control.
Traps in Questions
The traps are usually about diagnosis versus description. Inspectors describe what they observe and identify material defects; they do not certify capacity, efficiency, or remaining life. Another trap is cause versus symptom: a stain may indicate an active or past leak, and the report should state the observation and recommend further evaluation. Questions may also test whether a condition is a defect or normal wear, and whether it is within the scope of a visual inspection.
Worked Rule of Thumb
When in doubt, describe the condition, state its implication, and recommend evaluation. Example: a double-tapped breaker is a safety concern; report it as a defect and recommend correction by a qualified electrician. Do not attempt to repair or predict failure timing.