Achieving High-Performance Energy Buildings

Achieving a high-energy performance building, whether following the NZEB (Nearly Zero Energy Building), ZEB (Zero Emission Building), or any other energy-efficient standard, requires a holistic and detailed approach from design through construction and into the operational phase. The key principles that guide the process include the integration of energy-efficient materials, systems, and designs, with careful oversight and testing to ensure each component performs as intended. Below is a comprehensive guide to the key steps and considerations for achieving a high-performance energy building.

1. Engage Qualified Experts and Certified Professionals

The design, construction, and operation of high-performance buildings are complex processes that demand expertise from specialists with specific knowledge, certifications, and experience in sustainable building practices. These professionals include architects, engineers, energy consultants, and construction supervisors with recognized certifications such as:

Passive House Certified Designer or Consultant
LEED Accredited Professionals (AP)
Building Performance Institute (BPI) Certification
Certified Energy Managers (CEM)
Qualified technicians for air tightness testing and thermal imaging

Involvement of qualified professionals ensures that the building meets the desired energy performance targets and adheres to relevant standards, such as the Energy Performance of Buildings Directive (EPBD).

2. Comprehensive Planning and Integrated Design

Achieving high energy performance starts with meticulous planning and a commitment to an integrated design approach, where energy efficiency is considered from the earliest stages of development. The entire building system must work together, which involves:

Site Orientation: Maximizing natural lighting, shading, and ventilation, reducing heating and cooling loads.
Building Envelope: Incorporating materials and systems such as high-performance insulation, thermal breaks, and air-tight membranes to minimize energy loss.
Windows and Doors: Using triple-glazed windows, low-emissivity coatings, and thermally broken frames to reduce heat transfer.
Mechanical Systems: Designing efficient heating, cooling, and ventilation systems, including heat recovery ventilation (HRV), and integrating renewable energy sources like solar panels or geothermal systems.

All elements, from materials selection to system configurations, should be planned to minimize energy consumption and enhance comfort for occupants.

3. Supervision and Testing During Construction

The importance of careful supervision and quality control during the construction process cannot be overstated. Every component and material must be installed according to the detailed design to ensure optimal performance. Key elements that should be closely supervised and tested include:

Thermal Insulation: Ensuring the correct installation of insulation materials to avoid gaps or compression, which can lead to thermal bridges.
Air Tightness: Verifying through blower door testing that the building envelope is airtight, reducing energy losses and preventing drafts.
Thermal Bridges: Testing junctions and connections in the building envelope to identify and minimize thermal bridging, a major source of energy loss.
Ventilation: Testing the airflow and efficiency of ventilation systems to ensure proper function, particularly for heat recovery systems, which are critical in reducing heating and cooling loads.

Ensuring that testing and verification happen at different stages of construction is critical for identifying issues early and avoiding costly rework or retrofits later on.

4. Commissioning and Monitoring

Once construction is completed, commissioning the building’s energy systems is essential to verify that all systems operate as designed. This includes testing the performance of heating, cooling, and ventilation systems, as well as ensuring that renewable energy systems, such as solar panels, are integrated and functioning efficiently. Smart energy monitoring systems can be employed to track the building’s energy performance in real-time, helping identify areas for optimization and ensuring the building meets its energy goals throughout its lifecycle.

5. Maintenance and Continuous Improvement

High-performance buildings, like all buildings, require regular maintenance to ensure their energy systems continue to operate at optimal efficiency. Key maintenance tasks include:

HVAC System Maintenance: Regular cleaning and calibration of heating, cooling, and ventilation systems to maintain high efficiency.
Insulation and Air Tightness Inspections: Checking for any breaches in the building envelope or areas where air tightness or insulation may be compromised over time.
Window and Door Maintenance: Ensuring that seals remain intact and that there is no air leakage from these critical points in the building envelope.
Energy Monitoring: Continuously monitoring energy consumption and system performance, using data to adjust operations and increase efficiency where needed.

Regular maintenance ensures that the initial energy savings designed into the building persist over its lifetime and helps to identify opportunities for further improvements.

6. Use of Low Embodied Carbon Materials

In addition to operational energy efficiency, reducing the embodied carbon of the materials used in construction is an emerging priority for high-performance buildings. Materials with low embodied carbon, such as sustainably sourced timber, recycled content, or high-efficiency prefabricated components, contribute to the overall environmental performance of the building. Certification schemes such as BREEAM or DGNB may include specific criteria for evaluating embodied carbon and resource efficiency.

7. Compliance with Certification Standards

To ensure that a building achieves the desired energy performance standard, it must comply with the relevant certification schemes, such as:

Passive House: One of the most stringent energy efficiency standards focusing on super-insulation, air tightness, and high-efficiency mechanical systems.
LEED (Leadership in Energy and Environmental Design): A widely recognized green building certification that addresses energy performance along with other sustainability criteria.
BREEAM (Building Research Establishment Environmental Assessment Method): A certification that assesses the overall sustainability performance of buildings, including energy use.
DGNB (German Sustainable Building Council): A certification focusing on the lifecycle and holistic sustainability of buildings.

Certification ensures that the building adheres to the highest standards of energy efficiency and sustainability, providing a framework for both the design and operational phases.

Conclusion

Building a high-energy performance building, whether NZEB, ZEB, or any other standard, requires the integration of advanced design, construction, and operational practices. The collaboration of certified professionals, comprehensive planning, supervision during construction, and ongoing maintenance are critical elements in delivering a building that performs efficiently over its entire lifespan. By focusing on both the operational energy performance and the use of low embodied carbon materials, high-performance buildings can significantly contribute to reducing carbon emissions and enhancing overall sustainability.