BPI HEP Energy Auditor flashcards
BPI HEP Energy Auditor · Build recall with a focused review session.
31 cards. Read the term and the definition here. The deck at the top of this page is optional.
- Stack effect
- Buoyancy-driven airflow caused by indoor-outdoor temperature differences; warm air rises and exits high while cold air enters low, producing pressure differences that increase with building height.
- Thermal boundary
- The continuous insulation layer separating conditioned from unconditioned space; gaps or breaks in this boundary create thermal bridging and localized heat loss.
- Air barrier
- The continuous material that resists airflow across the building enclosure; it must be sealed at penetrations and transitions to control infiltration and exfiltration.
- Vapor retarder placement
- Vapor retarders belong on the warm side of the assembly; cold-climate assemblies place them inside, while hot-humid assemblies avoid interior retarders to allow inward drying.
- U-value
- The rate of heat transfer through an assembly per unit area and temperature difference; it equals the reciprocal of R-value and includes framing and other thermal bridges.
- Sensible heat formula
- Air heat content change equals 1.08 times airflow in CFM times the dry-bulb temperature difference; used to calculate heating or cooling delivered by an air stream.
- Dew point
- The temperature at which air reaches saturation and moisture condenses; locating it within an assembly identifies surfaces at risk of hidden condensation and decay.
- Blower door CFM50
- Airflow measured at 50 Pa depressurization; it quantifies envelope leakage and, divided by conditioned floor area, gives a normalized airtightness benchmark.
- Effective leakage area
- An estimate of the total equivalent hole size in the envelope, derived from blower door data and referenced to 4 Pa; useful for comparing homes of different size.
- Duct leakage to outside
- Leakage from the duct system to unconditioned space, measured by combining duct blaster and blower door tests; it wastes conditioned air and degrades pressure balance.
- Zone pressure diagnostic
- A test using multiple pressure taps and a calibrated fan to map which building cavities connect to conditioned space and where leakage paths cross the pressure boundary.
- Combustion appliance zone
- The space containing combustion equipment; testing measures worst-case depressurization with exhaust fans running to confirm appliances vent safely without spillage.
- Spillage
- Combustion gases escaping from an appliance draft hood into the room rather than up the flue; detected by flame or smoke observation and CO monitoring.
- Infrared thermography
- Thermal imaging that reveals surface temperature differences; interpretation requires adequate indoor-outdoor temperature difference and confirmation of suspected air leaks or missing insulation.
- Static pressure
- The resistance to airflow in a duct system, measured across the air handler; excessive static pressure reduces delivered airflow and indicates restrictive filters, coils, or ducts.
- Moisture content
- The percentage of water by weight in a material such as wood; readings above about 20 percent indicate conditions favorable for mold growth and decay.
- Degree-day method
- An energy estimating technique using heating or cooling degree days multiplied by building conductance; it approximates annual space-conditioning energy from weather data.
- UA calculation
- The sum of each envelope area multiplied by its U-value; total UA times the indoor-outdoor temperature difference gives steady-state heat loss in Btu per hour.
- Base load
- The portion of utility consumption not driven by outdoor temperature, such as water heating, appliances, and lighting; separating it improves weather-normalized savings estimates.
- Simple payback
- Installed measure cost divided by estimated annual energy savings; it ignores fuel escalation and measure life, so it is paired with life-cycle analysis.
- Savings to investment ratio
- The present value of lifetime savings divided by installed cost; values above one indicate the measure returns more than its cost over the analysis period.
- Marginal savings
- The incremental savings from each additional measure; it declines as improvements accumulate, so measure order affects total predicted savings.
- Weather normalization
- Adjusting consumption data for heating or cooling degree days so that different years or homes can be compared on a common basis.
- Measure prioritization
- Ranking improvements by health and safety first, then durability and moisture, then envelope, HVAC, and controls; economics inform but do not override safety.
- Work scope
- A written document specifying each measure, quantity, material, and sequence, with test-in and test-out requirements and clear separation of safety items.
- ASHRAE 62.2
- A residential ventilation standard specifying whole-building and local exhaust rates based on floor area and bedroom count; referenced after air sealing tightens a home.
- Worst-case depressurization
- The maximum negative pressure in a combustion appliance zone with all exhaust fans operating and interior doors closed; it determines combustion safety risk.
- Informed consent
- Documented client agreement to recommended measures after being told of costs, benefits, and any health or safety tradeoffs of the proposed work.
- Test-in and test-out
- Pre-work and post-work diagnostic measurements such as blower door and combustion tests that document baseline conditions and verify achieved performance.
- Change order
- A written modification to the agreed scope when field conditions differ from the audit, documenting added or removed measures and revised pricing before work proceeds.
- Quality assurance inspection
- Post-installation verification that measures meet specification, including visual checks and diagnostic retesting, with results compared to the original audit baseline.