Insulation & Ventilation Inspection Flashcards

What is the primary function of soffit vents in an attic ventilation system?

Answer: Provide cool intake air at the lower roof edge

Soffit vents serve as the intake air source at the lowest point of the roof, allowing cool fresh air to enter and push hot, moist air out through ridge or gable vents higher in the attic.

Which insulation material provides the highest R-value per inch of thickness?

Answer: Closed-cell spray foam

Closed-cell spray polyurethane foam provides approximately R-6 to R-7 per inch, significantly higher than other common residential insulation materials.

What roof-related condition commonly results from inadequate attic ventilation combined with excessive heat loss through the ceiling in cold climates?

Answer: Ice dams

Ice dams form when heat escaping through a poorly ventilated attic melts snow on the roof surface, which then refreezes at the cold eave and can force water under shingles causing interior damage.

When installing faced fiberglass batt insulation in exterior wall cavities in a cold climate, where should the vapor retarder facing be oriented?

Answer: Toward the warm-in-winter (interior) side of the wall

The vapor retarder facing must be installed on the warm-in-winter side (interior) to prevent moisture-laden indoor air from diffusing into the wall assembly where it can condense on cold surfaces.

What type of ventilation relies solely on natural forces such as temperature differences and wind pressure to move air, without any mechanical equipment?

Answer: Natural ventilation

Natural ventilation uses buoyancy (stack effect) and wind pressure differentials to move air through openings in the building envelope without any fans or powered equipment.

During a crawl space inspection, which observation should a home inspector flag as a deficiency requiring correction?

Answer: Evidence of moisture staining or mold on the insulation and framing

Moisture staining or mold on crawl space insulation or wood framing indicates water intrusion or inadequate vapor control that can lead to structural deterioration and poor indoor air quality.

What is the primary concern when cellulose insulation becomes saturated with water due to a leak or flooding?

Answer: It compresses, promotes mold growth, and retains moisture causing long-term structural damage

Wet cellulose compresses significantly, losing R-value permanently, and retains moisture that promotes mold growth and wood rot in surrounding structural members.