ULTRA-EFFICIENT BUILDING STANDARD

PASSIVE HOUSE

The world's most rigorous voluntary energy-based standard - achieving up to 90% reduction in heating and cooling energy

Passive House (Passivhaus) is a performance-based building standard that creates ultra-comfortable, energy-efficient buildings requiring minimal heating and cooling.

Originating in Germany, Passive House has become the gold standard for energy efficiency worldwide, with buildings that use up to 90% less energy than conventional construction.

THE RESULT

Buildings so efficient they can be heated by body heat, sunlight, and everyday activities - with minimal active heating systems.

FIVE CORE PRINCIPLES

1. Superinsulated Envelope

Continuous insulation throughout the building envelope with typical U-values of 0.10–0.15 W/m²·K

Prevents heat loss and maintains stable indoor temperatures

2. Airtight Construction

Achieve n50 ≤ 0.6 air changes per hour at ±50 Pa during blower-door testing

Eliminates drafts and uncontrolled air infiltration

3. High-Performance Windows & Doors

Triple/quad glazing with low-e coatings and whole-window U-values ≤0.80 W/m²·K

Minimize heat transfer while maximizing solar gains

4. Thermal-Bridge-Free Design

Continuous insulation with psi-values below 0.01 W/(mK) at all junctions

Prevent cold spots and energy loss at connections

5. Heat Recovery Ventilation

Mechanical ventilation with ≥75% sensible heat recovery efficiency

Fresh air continuously while recovering energy

PERFORMANCE STANDARDS

Space Heating Demand

Requirement:≤ 15 kWh/m²/year

Alternative:

OR peak heat load ≤ 10 W/m²

Annual heating energy use per square meter

Airtightness

Requirement:n50 ≤ 0.6 ACH

Alternative:

1.0 ACH for EnerPHit (retrofits)

Air changes per hour at 50 Pascals pressure

Total Primary Energy

Requirement:≤ 60 kWh/m²/year

Alternative:

Renewable energy sources

All energy use including heating, cooling, hot water, lighting, appliances

Overheating

Requirement:< 10% hours above 25°C

Alternative:

Passive cooling strategies

Thermal comfort without active cooling

MODERN CONSTRUCTION TECHNIQUES

Factory-made systems reduce errors and offer greater precision in achieving airtightness and thermal performance

Double-Stud Walls

Two parallel stud walls with continuous insulation in the gap

No thermal bridging through studs

Insulated Concrete Forms (ICF)

Interlocking foam panels filled with concrete

Eliminates need for additional insulation layers

Structural Insulated Panels (SIPs)

Factory-made sandwich panels with foam core

Greater precision and reduced installation errors

Cross-Laminated Timber (CLT)

Engineered wood with layers oriented at right angles

Carbon-negative and excellent thermal performance

HIGH-PERFORMANCE WINDOWS

Glazing

Triple or quad-pane with low-e coatings

U-value ≤0.80 W/m²·K

Gas Fills

Argon or krypton between panes

Reduces conductive heat transfer

Warm-Edge Spacers

Low-conductivity spacer materials

Prevents condensation at edges

Installation

Positioned in line with insulation layer

Minimizes thermal bridging

CRITICAL: Window Position

Windows must be positioned to line up with the insulation layer and minimize thermal bridging at the frame. The gasket forms a tight seal when compressed in the locked position - testing in unlocked position can compromise results.

HEAT RECOVERY VENTILATION

HRV (Heat Recovery Ventilator)

Function

Exchanges heat only between airstreams

Efficiency

Up to 90% heat recovery

Best For

Best for cold/dry climates

ERV (Energy Recovery Ventilator)

Function

Exchanges both heat and moisture

Efficiency

Up to 90% total energy recovery

Best For

Best for humid climates

DUCTLESS OPTIONS AVAILABLE

Ductless HRV/ERV systems provide fresh air without extensive ductwork, perfect for retrofits or spaces where traditional installation is impractical. Systems like Zehnder fit in 2×4 walls and exceed Passive House energy requirements.

BLOWER DOOR TESTING

Essential verification that the building meets airtightness requirements

1

Preparation

Close all windows, doors, and intentional openings. Open all interior doors.

2

Fan Installation

Install calibrated fan in main exterior door opening, typically covering entire doorway.

3

Pressure Test

Generate 50 Pascals pressure difference between inside and outside.

4

Measurement

Measure air leakage rate to calculate n50 (air changes per hour at 50 Pa).

5

Leak Detection

Use thermal cameras or smoke to identify air infiltration points.

6

Verification

Must achieve n50 ≤ 0.6 ACH for Passive House certification.

LEAK DETECTION TOOLS

During testing, thermal cameras or smoke detectors visually identify air infiltration points. Common weak areas include: joints, doors/windows, unsealed connections, and gaskets. Early detection allows for immediate fixes.

PROVEN ENERGY SAVINGS

90% reduction

Heating/Cooling Energy

vs. conventional buildings

60-70% reduction

Total Energy Use

vs. code minimum

75-90% reduction

Peak Heating Load

Smaller HVAC systems needed

THE BOTTOM LINE

Passive House buildings provide superior comfort, exceptional air quality, and massive energy savings - making them the future of sustainable construction.

CONTINUE LEARNING

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