Insulation & Ventilation Inspection Flashcards
7 cards from real CHI practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Insulation & Ventilation Inspection flashcards as text
What is the minimum recommended R-value for attic insulation in most U.S. climate zones (Zones 4-8) according to Department of Energy guidelines?
Answer: R-38
The DOE recommends a minimum of R-38 for attic insulation in climate zones 4-8, with R-49 or higher for optimal energy efficiency.
Which insulation material commonly found in pre-1980s homes is highly fire-resistant but poses significant health hazards when its fibers are disturbed?
Answer: Asbestos
Asbestos was widely used before the 1980s for its fire-resistant properties but is now known to cause serious respiratory diseases such as mesothelioma when its fibers become airborne.
What is the primary purpose of a vapor barrier installed on the ground in a crawl space?
Answer: To prevent ground moisture from migrating upward into the structure
A ground vapor barrier in a crawl space primarily prevents soil moisture from evaporating upward and causing condensation, rot, and mold in the floor framing.
What does 'thermal bridging' refer to in the context of building insulation?
Answer: Conductive heat transfer through structural elements that bypass the insulation layer
Thermal bridging occurs when structural members like wood studs or metal framing conduct heat more readily than the surrounding insulation, reducing the overall thermal performance of the wall assembly.
Which mechanical ventilation strategy uses both supply and exhaust fans to maintain balanced air pressure within a home?
Answer: Balanced ventilation
Balanced ventilation systems use supply and exhaust fans simultaneously to maintain neutral air pressure, preventing the infiltration or exfiltration problems associated with unbalanced systems.
What is the minimum net free ventilation area (NFVA) typically required for attic spaces without a vapor barrier, expressed as a ratio of the attic floor area?
Answer: 1/150
Building codes typically require a minimum of 1/150 of the attic floor area as net free ventilation area when no vapor barrier is present; this ratio drops to 1/300 when a vapor barrier is installed.
Which insulation installation method delivers loose material pneumatically through a hose into attic spaces or enclosed wall cavities?
Answer: Blown-in (loose-fill) installation
Blown-in or loose-fill insulation is delivered pneumatically, allowing it to fill irregular spaces and achieve uniform coverage in open attics or enclosed cavities where batts would be difficult to install.