Certified Passive House Designer / Consultant flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Heating demand limit

Maximum allowed annual heating demand for Passive House certification is 15 kWh per square meter of treated floor area per year, calculated using the PHPP method.

Primary energy limit

Passive House certification requires primary energy demand not exceeding 60 kWh per square meter of treated floor area per year, including all energy uses.

Airtightness criterion

The building envelope must achieve an n50 value of 0.6 air changes per hour or less at 50 Pa pressure difference, verified by a pressurization test.

Thermal comfort criterion

Operative temperature must not exceed 25 degrees Celsius for more than 10 percent of hours during the cooling season, as verified in PHPP.

U-value formula

U-value equals the reciprocal of the sum of internal surface resistance, layer resistances (thickness divided by thermal conductivity), and external surface resistance.

Thermal bridge penalty

The additional heat loss due to thermal bridges is calculated as the linear thermal transmittance multiplied by the length of the bridge divided by the area.

Airtightness layer continuity

The airtight layer must be continuous and seal all penetrations, including cables and pipes, using gaskets and membranes to avoid leaks.

Insulation thickness for U-0.15

To achieve a U-value of 0.15 watts per square meter kelvin, typical insulation thickness is 20 to 30 centimeters for thermal conductivity 0.035 to 0.040.

Window U-value formula

Window U-value is calculated as the area-weighted average of glazing and frame U-values plus the linear thermal bridge at the glazing edge, divided by total area.

Triple glazing requirements

For Passive House certification, glazing U-value should be 0.8 watts per square meter kelvin or lower, with a frame U-value of 1.0 or lower.

Solar heat gain coefficient

The solar heat gain coefficient (g-value) indicates the fraction of solar radiation admitted through glazing; it should be high for passive heating and low for cooling.

Window installation position

Windows should be installed within the insulation layer, with airtight connections and thermal breaks at the frame to minimize thermal bridging.

Ventilation rate

Minimum ventilation rate for Passive House is typically 0.3 air changes per hour based on occupancy, ensuring indoor air quality while minimizing heat loss.

Heat recovery efficiency

Passive House ventilation systems require a heat recovery efficiency of at least 75 percent, achieved with a counterflow heat exchanger.

Duct design pressure drop

Ventilation ducts should be designed for low pressure drops, typically below 100 pascals, using smooth ducts and avoiding sharp bends to reduce fan energy.

Summer comfort strategy

To avoid overheating, use external shading, night ventilation, and high thermal mass; PHPP verifies that overheating hours remain below 10 percent.

Heating load limit

The maximum heating load for Passive House certification is 10 watts per square meter of treated floor area, ensuring minimal heating system size.

Domestic hot water demand

Typical domestic hot water demand is 30 to 60 liters per person per day at 60 degrees Celsius, often met by solar thermal or heat pumps.

Heat pump COP

For Passive House, heat pumps should have a coefficient of performance of at least 3.5 to ensure efficient heating and domestic hot water generation.

Renewable energy integration

Renewable energy sources such as solar thermal and photovoltaics can reduce primary energy demand and are accounted for in the PHPP calculation.

Heating demand formula

Annual heating demand is the sum of transmission losses, ventilation losses, minus solar gains and internal gains, calculated monthly in PHPP.

Primary energy factor

Primary energy factor converts final energy to primary energy; for grid electricity it is typically 1.8 to 2.4, while for renewables it can be near zero.

PHPP verification criteria

PHPP verification requires heating demand of 15 kWh per square meter per year or less, primary energy of 60 or less, and airtightness of 0.6 or less.

Summertime overheating check

PHPP verifies that the frequency of operative temperatures above 25 degrees Celsius does not exceed 10 percent of hours during the cooling period.

Life-cycle cost analysis

Economic assessment of Passive House should consider life-cycle costs, including construction, energy, maintenance, and subsidies, compared to conventional buildings.

Independent quality assurance

An independent PHI-certified verifier checks the PHPP, construction documents, and on-site work to ensure compliance with Passive House criteria.

Construction supervision stages

On-site inspections should occur at key stages: airtightness layer installation, insulation placement, window installation, and ventilation system commissioning.

Commissioning airtightness test

A pressurization test measures the n50 value; a trained technician conducts it and provides a report including leakage locations and the measured value.

Ventilation commissioning

Commissioning involves measuring air flows at each terminal, adjusting dampers to design values, and verifying heat recovery efficiency and system balance.

Certification documentation

Certification requires submission of PHPP, as-built drawings, airtightness test report, and commissioning report to PHI or an accredited certifier.

Certification validity

Passive House certification is valid for five years; re-certification may require updated documentation and verification of continued compliance.

Thermal bridge avoidance

Avoid thermal bridges by wrapping insulation continuously around corners and using thermal break elements for balconies and other penetrations.