Passive House Construction: The Rigorous Building Performance Standard With Specific Envelope and Mechanical Requirements
Passive House is performance-based energy standard originally developed in Germany (Passivhaus Institute) and adapted for North American climate by PHIUS (Passive House Institute US). Certified Passive House buildings achieve heating demand under 15 kWh/m²/year (PHI) or climate-specific limits (PHIUS) with airtight envelope (0.6 ACH50 for PHI; climate-based for PHIUS), thermal bridge-free construction, and balanced mechanical ventilation with heat recovery.
Passive House is more rigorous than LEED or WELL — specific performance targets verified through testing, not just design credits. Single-family homes, multifamily, schools, and commercial buildings all achieve certification. Understanding construction requirements helps contractors deliver certifiable projects. This post covers Passive House fundamentals.
Two major certification bodies:
Passive House certification
- PHI (Passive House Institute) — German origin, international
- PHIUS (Passive House Institute US) — North American climate-adapted
- PHI Classic — original metrics (15 kWh/m²/yr heating)
- PHIUS+ 2021 — climate-specific metrics
- Different certifying entities and processes
- Similar principles, different metrics
Two major programs have different metrics. PHI uses original European targets. PHIUS adapts to North American climates. Some projects pursue both; most choose one. Program selection affects design targets and verification process.
Extreme air tightness required:
Air tightness requirements
- PHI — ≤0.6 ACH50 (air changes per hour at 50 Pa)
- PHIUS — climate-specific, typically 0.05 CFM/sf shell at 50 Pa
- Blower door testing verifies
- Whole-building envelope sealed
- Every penetration addressed
- Air barrier continuity critical
- Multiple tests during construction
Passive House air tightness is 5-10x tighter than typical new construction. 0.6 ACH50 is approximately 95% less leakage than standard construction. Requires detailed design and careful construction. Blower door testing at envelope completion verifies. Testing before finishes installed allows correction.
High insulation and thermal bridge reduction:
Thermal performance
- Super-insulated envelope
- Continuous insulation outside structure
- Thermal bridge-free construction
- High-performance windows (typically triple glazed)
- Well-insulated foundation/slab
- Roof insulation significantly exceeding code
- Balanced thermal performance across envelope
Envelope insulation substantially exceeds code. Continuous insulation outside structural layer eliminates thermal bridges through studs or framing. Triple-glazed windows with low-emissivity coatings. Foundations insulated on exterior or below slab. Every penetration thermally addressed.
Thermal bridges analyzed and mitigated:
Thermal bridge treatment
- 3D thermal modeling during design
- Psi values calculated for details
- Isothermal planes through envelope
- Continuous insulation preventing bridges
- Structural thermal breaks
- Foundation detail analysis
- Documentation for certification
Thermal bridges (conductive paths through insulation) create heat loss and condensation risk. Passive House eliminates or minimizes bridges through design. Thermal modeling quantifies remaining bridges. Construction must maintain designed conditions. Details matter at every junction.
Mechanical ventilation with heat recovery:
Passive House ventilation
- HRV (Heat Recovery Ventilator) or ERV (Energy Recovery Ventilator)
- Balanced supply and exhaust
- High heat recovery efficiency (75-90%+)
- Continuous operation at low rates
- Bedroom supply, wet-room exhaust typically
- Ducted distribution
- Commissioning to verify flows
Airtight envelope requires mechanical ventilation. HRV/ERV recovers heat from exhaust air to condition incoming air. Substantial energy savings versus standard ventilation. High efficiency recovery units cost more but reduce energy use significantly. Commissioning confirms proper installation.
Windows are specialized:
Passive House windows
- Triple glazing typical
- U-value ≤0.15 W/m²K (PHI) typical
- Warm edge spacers
- Thermally broken frames
- Solar heat gain balanced with heating demand
- Installation with air and thermal continuity
- Window-wall interface detailed
Windows are significant envelope component. Triple glazing with low-e coatings typical. Frame thermal performance matches glazing. Installation details maintain air barrier and thermal continuity. Specialized installers understand requirements; general installers often don't achieve required performance.
Blower door test is moment of truth for Passive House. Months of construction effort converge to a measured result — pass or fail. Contractors committed to Passive House practice envelope detailing rigorously throughout construction. Blower door test isn't hoped-for outcome; it's planned outcome. Teams that treat it as hope fail; teams that plan for it succeed.
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Construction Coordination
Coordination throughout:
Construction coordination
- Air barrier installer coordination
- Insulation continuity
- Window installation per details
- Penetrations through envelope minimized and sealed
- Rough-in coordination
- Temporary protection of envelope
- Mid-construction blower door tests
Every trade affects envelope performance. MEP penetrations must be sealed. Thermal bridging from framing attention. Window installation critical. Temporary construction damage repaired. Mid-construction testing catches issues while accessible.
Heating/cooling systems smaller:
Mechanical systems
- Small heating load (superior envelope)
- Heat pumps common
- Radiant systems sometimes
- Simple systems for small loads
- HRV/ERV for ventilation
- Domestic hot water efficient
- Solar augmentation often
Passive House envelope reduces heating/cooling loads substantially. Smaller equipment suffices. Heat pumps common. Less complexity. DHW may be larger proportional load than heating. Renewable energy often covers remaining small loads.
PHPP or WUFI Passive modeling:
Energy modeling
- PHPP — Passive House Planning Package (PHI)
- WUFI Passive (PHIUS)
- Detailed energy modeling
- Verifies design meets criteria
- Iterative design refinement
- Submitted for certification
Specific energy modeling software used for Passive House. PHPP for PHI; WUFI Passive for PHIUS. Models predict annual energy performance. Submitted with certification documentation. Design iterates until model meets criteria.
Passive House premium varies:
Cost considerations
- 5-15% cost premium typical (varies by market)
- High-performance windows
- Additional insulation
- HRV/ERV equipment
- Smaller heating/cooling equipment offsets
- Operating energy savings
- Incentives sometimes available
Premium varies by market experience. Mature markets with experienced teams have smaller premium. First project in market has larger premium. Operating savings over decades often justify premium. Incentives in some markets offset costs further.
Passive House is rigorous performance standard with certified buildings achieving exceptional air tightness, thermal performance, and low energy use. PHI and PHIUS provide certification with specific metrics. 0.6 ACH50 air tightness (or climate-specific equivalents) verified by blower door. Super-insulated thermal bridge-free envelope. HRV/ERV mechanical ventilation. Triple-glazed high-performance windows. Detailed construction coordination across trades. Energy modeling via PHPP or WUFI Passive. Cost premium 5-15% typical offsetting with operating savings. Contractors committed to Passive House practice envelope details rigorously; contractors treating it as preferences miss certification. Climate change concerns and energy cost pressures are driving Passive House adoption. For contractors pursuing high-performance building market, Passive House capability is significant differentiator.
Written by
Jordan Patel
Compliance & Legal
Former corporate counsel specializing in construction contracts and tax compliance. Writes about the documentation layer — COIs, W-8/W-9, certified payroll, notice-to-owner deadlines — and the legal backbone behind audit-ready AP.
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