Passive House Performance Standards
A “Passive House” refers to a highly energy-efficient building that minimizes energy consumption through the use of passive design strategies. By fully utilizing renewable energy sources such as solar, air, and geothermal energy, the total consumption of primary energy does not exceed 120 kWh/(m2·a). The concept of passive houses is applicable worldwide and can be implemented in both cold and warm climates. Additionally, the construction methods are not limited by building types — passive design can be applied to office buildings, residential homes, schools, sports facilities, and industrial buildings.
In industrial buildings, lightweight handling equipment such as a 1 ton gantry crane is increasingly being adopted to balance energy-saving goals with operational efficiency.
Key Technologies for Reducing Energy Consumption in Passive Houses
A passive house emphasizes “passive” strategies, meaning the technologies used do not involve moving components (such as valves, pumps, or engines), complex control systems, or sophisticated mechanical equipment. The active technologies employed should be simple, easy to install and maintain, have a low failure rate, and a long service life.
Such ultra-low energy consumption is achieved through highly insulated and soundproofed building envelopes, excellent airtightness, and the use of renewable energy sources. The design philosophy advocates for a “fabric first” approach, focusing on five key technologies: thermal insulation, thermal bridge elimination, energy-efficient windows and doors, airtight construction, and a mechanical ventilation system with heat recovery.
1. Building Orientation
The first consideration for energy-efficient housing should be the building’s location and orientation. The design should aim to maximize passive solar gains while minimizing heat gain during the summer. Simple adjustments related to direction and design can significantly improve comfort — allowing natural warmth in winter without overheating in summer. Well-designed control of passive solar gain helps reduce heating demand in winter and cooling load in summer.
2. Window Design
Energy-efficient window design should be based on the actual conditions of the building’s location. Flexibility is essential. It must consider the climate, building comfort requirements, solar radiation, and air circulation. When designing exterior windows, one should analyze the orientation of the building, the distance between buildings, and their spatial relationship. Environmental factors must be comprehensively considered to ensure lighting, ventilation, aesthetics, and optimized window-to-wall ratios. Proper window type and enhanced sealing performance help minimize air infiltration and heat transfer, thus improving the scientific and rational use of natural resources.
3. Heat Recovery
Heat recovery should be another essential part of any energy-efficient residential design. As previously mentioned, there are many advanced ventilation technologies. Although relatively new to the domestic market, they can greatly improve a home’s energy performance. Technologies like flue gas heat recovery (FGHRS) or wastewater heat recovery systems offer additional energy and cost savings.
4. Airtightness
Improving the airtightness of a building is often considered the most cost-effective method to reduce energy loss for space heating and cooling. It also enhances indoor comfort and air quality. Achieving a high level of airtightness involves more than filling visible gaps — it requires several carefully planned steps. First, define the insulation boundary. Then, ensure a continuous airtight barrier along the entire envelope. The key is to maintain continuity.
This can be achieved by identifying large materials, such as external sheathing or internal drywall, and bridging the gaps or joints between them to create a fully sealed boundary. Next, choose the most suitable airtightness method for your project. Several effective techniques are available, including the use of airtight drywall and the bonding of structural framing with sheathing. Proprietary systems like SIGA and ZIP provide excellent solutions but may be costlier. A newer option, aerosol-based sealing technology, has achieved extremely high levels of airtightness.
In some industrial buildings equipped with large machinery, such as a 10 ton overhead crane, airtight design can be even more challenging. These facilities not only require wide-span structural support but must also strike a balance between equipment access, track installation, and maintaining airtight performance.
5. Daylight Design
Lighting and daylighting must meet occupants’ visual and psychological needs. Nowadays, people spend most of their time indoors, so it is essential to carry out thoughtful daylighting design, particularly for office buildings. Avoid problems such as glare, reflections, or lighting that is too intense or too dim. Residential spaces like bedrooms, kitchens, and living rooms should also have access to natural light. This design should meet modern expectations of advanced architecture while enhancing energy efficiency.
Artificial lighting typically generates more heat and consumes more energy than daylight. Therefore, maximizing the use of sunlight to regulate indoor thermal conditions can greatly reduce energy consumption. Daylighting not only fulfills lighting needs but also improves comfort and inhibits the growth of mold and microorganisms, contributing to environmental protection.
6. Solar-Powered Solutions
With rising energy costs showing no sign of decline, utilizing solar photovoltaic (PV) or solar thermal systems for self-sufficient energy generation or to supplement heating/hot water is a great design consideration. In many regions, surplus electricity can be sold back to the grid. Future systems may even allow energy storage for personal use.
While it’s hard to calculate ROI accurately due to market fluctuations, the upward trend in energy costs makes solar investment increasingly practical. Of course, the suitability of such technology depends on factors like latitude, system size, design flexibility, and installation orientation.
7. Insulation
Reducing heat loss through walls, floors, and other building components is critical for energy-efficient home design. Well-designed composite components can greatly minimize U-values and maximize R-values, providing long-term energy and cost benefits over the building’s lifecycle. Many effective insulation systems and materials are available, including ICFs (Insulated Concrete Forms), thicker wall assemblies, and roof insulation. Spray foam is also a widely accepted solution.
Designing a well-insulated, well-lit, efficiently heated building from the beginning is far easier than making improvements later. Consider local climate and geography from the outset and complement with passive shading strategies — this approach will pay dividends over time. For any architectural team, energy-efficient design should be a top priority.
8. Heating System Design
Building heating systems typically involve two main considerations:
First, large-volume buildings have much greater space compared to standard rooms, with more complex envelope structures. As a result, indoor temperature variations affect thermal comfort more significantly, and the heating system must be capable of handling higher pressure and demand.
Second, heating pipework must be designed in line with the building’s functional layout, with careful zoning and loop segmentation.
Designing a heating system for such buildings involves two main tasks. First, all terminal heat emitters must meet performance and energy efficiency standards. Second, the pipework layout should be simple and adjustable according to demand, minimizing pipe length to reduce installation costs and operational energy consumption.
