Passive House Standard is the world’s most rigorous energy performance standard. It meets the energy petal of Living Building Challenge projects. Passive House provides the points to achieve a LEED Gold rating when combined with LEED prerequisites. Passive House meets Ed Mazria’s AIA 2030 Challenge and approaches the 2050 Challenge.
Passive House differs from passive solar design, which relies on solar gain but poorly manages temperature and comfort fluctuations. Passive House Standard includes conservation-based strategies that are “permanent” to the building envelope with energy and durability performance well beyond minimum code-compliant buildings. Consequently, mechanical systems are smaller and more efficient.
The conservation approach to energy reduction is an enhanced super-insulated and airtight envelope – floors, walls, roofs, windows, and doors. Heating and cooling loads are reduced, powered by high-efficiency mechanical systems, including the essential energy/ heat recovery ventilator. A much smaller, less expensive solar array is needed to meet net-zero energy (although not required). Being “Solar Ready” is a Passive House requirement that anticipates adapting to a future all-electric, fossil fuel-free grid.
There are two certifying bodies: 1) Phius (Passive House Institute of US, phius.org) and 2) PHI (Passive House International, www.passivehouse.org). They have slightly different but equally rigorous requirements.
PASSIVE HOUSE BEST PRACTICES
– Climate-specific design
– Orientation for optimal solar gain in winter (in colder climates), with sun control in summer
– Energy use predicted by an envelope-targeted energy model
– High-efficiency HVAC systems (preferably all-electric)
– Super-insulated building envelope
– Airtight construction (5X tighter than IRC 2018 Building Code)
– Continuous fresh HEPA-filtered air via an energy- or heat-recovery ventilator
– Triple pane insulated windows doors (in our climate)
– Vapor open airtight construction to allow systems to ‘dry out,’ reducing water infiltration damage
– Reduction in embodied carbon (construction materials) and operational carbon (energy use)
– Resulting in:
• Improved thermal comfort
• Lower energy costs
• Filtered fresh air
• Reduced sound infiltration (where the air goes does sound)
• ‘Luxury’ performance
• Superior durability (lowered maintenance and replacement costs over time)
• Lower or no rodent invasions (they feel no warmth or smells)
• Lower dust requiring less cleaning
• Higher rents and building value.
1722 Pine Unit A is designed to meet EnerPHit, Passive House International’s retrofit standard for existing buildings. The upper floors applied PHI’s PnerPHit’s Step-by-Step approach to phased improvements. EnerPHit recognizes that developing a practical scope of work to meet the standard is more complex for renovations than new construction. A slightly relaxed airtightness standard acknowledges the numerous unknown and existing conditions in existing buildings, access limitations, constraints of existing materials, and past additions and repairs. The Passive House best practices and performance still apply.