Key Components of a Passive House

“A Passive house is a building in which a comfortable interior climate can be maintained without active heating and cooling systems”

(Adamson 1987 and Feist 1988).

The key components which distinguish a Passive house from both an Energy Efficient and standard houses include the following:

Passive House Key Components	Typical Standards Required in Ireland	Illustration
High Quality Insulation (Roof)	A U-value which does not exceed 0.15 W/(m²K).
Triple Glazed Windows	All windows must achieve a U-factor which does not exceed 0.8 W/(m²K).
Heat Recovery Ventilation	HRV is the renewal of indoor air using a Mechanical Heat Recovery Ventilation System; this limits the air humidity, pollutants and odours within the house whilst also recovering heat from the extract air.
High Quality Insulation (Block Walls)	A U-value which does not exceed 0.15 W/(m²K).
High Quality Insulation (Timber Frame Walls)
High Quality Insulation (ICF Walls)
High Quality Insulation (Foundations)	A U-value which does not exceed 0.12 W/(m²K).
Orientation	Southern orientation is the preferred choice.
Air Tightness	Air loss from unsealed joints throughout the entire house should not exceed 0.6 times the house volume per hour.
Preheated Fresh Air	Fresh air can be brought into the house using underground ducts which exchange heat with the soil. This fresh air can reach a temperature of 5°C even during the winter.
Hot Water Supply	This is achieved through the use of either solar collectors or heat pumps depending on personal choice.
Energy Saving Household Appliances	Low energy appliances are necessary in a Passive house.