Green buildings - Laying tomorrow’s foundations today

By by Dick van Dijk, Essam E. Khalil, Egil Öfverholm, Jonas Santesson & Stephen Turner

Expectations about what buildings should be like have dramatically changed over time. Now the industry must strive to meet demands for functionality, comfort and design together with environmental sustainability and energy efficiency. ISO has developed a toolbox of practical state-of-the-art International Standards to meet today’s building challenges.

More than 100 building standards have been developed by ISO technical committees ISO/TC 163, Thermal performance and energy use in the built environment, and ISO/TC 205, Building environment design. These standards help define, calculate and test building elements, while addressing environmental concerns. Design and building operation issues are also addressed by the committees.

Innovative insulation

Three ISO/TC 163 subcommittees (SCs) are responsible for the standards that define, calculate and test building elements, which are essential for ensuring the energy efficiency of buildings.

The SCs take into account the different specifications, challenges and innovations in the building industry. For example, a newcomer for building standardization is sheep wool insulation – a renewable material offering good thermal and acoustic insulation performance as well as protection against fire. In contrast to some other insulation types, wool’s uniquely high moisture absorption is not compromised by its isolating performance.

At the other extreme of the spectrum are high-tech insulation materials such as vacuum insulation panels (VIPs), which have very low thermal conductivity. Thin, VIC-based walls can help to maximize usable interior space and offset high land prices, and can be useful in the thoughtful renovation of culturally historic buildings.

A matter of design

ISO/TC 205 has published standards offering an integrated methodology for the design of high-performance indoor environments. These standards exist within the overarching framework of ISO 16813:2006, Building environment design - Indoor environment - General principles.

The comprehensive package of solutions developed with experts from around the world tackles energy-efficient and indoor environmental quality design. The standards also cover building automation control systems, radiant systems and other systems that relate directly to the indoor environment.

Notably, the standards aim to respond to design challenges while addressing sustainability concerns. As technology and expectations evolve, so does the work of ISO/TC 205, in order to ensure continual benefits.

Commissioning

Building commissioning refers to the quality process to verify and document that the completed project meets the owner’s needs. Commissioning at some level is required for building projects to achieve a rating or certification under the leading green building rating systems. Often, the minimum accepted is commissioning during construction, which includes functional performance testing of energy-related systems.

These systems also give additional credit to projects such as commissioning involvement during design. In comprehensive commissioning processes, design-phase commissioning activities provide vital quality-related enhancements to the design process.

Such enhancements also set the stage for meaningful commissioning activities in post-design project stages. ISO/TC 205 plans to include the design-related aspects of commissioning in its future standardization work. Through these and similar forward-looking initiatives, ISO’s standards for indoor environmental design will remain relevant.

The holistic approach

ISO/TC 205 collaborates closely with ISO/TC 163, including in the adoption of new work items, as these are needed to improve the standardization of the design process. A joint working group (JWG) helps coordinate common areas between both committees and has developed a holistic approach to address buildings’ energy performance.

Under this approach, energy performance comprises :

Heating

Cooling

Lighting

Ventilation

Domestic hot water

Appliances (in some cases)

The approach can be applied to evaluate the energy performance of badly insulated existing buildings, for example, compared to that of new, nearly zero-energy buildings, in order to assess compliance with minimum primary energy performance requirements in building regulations. A nearly zero-energy performance can only be achieved if all expertise and disciplines are effectively combined and coordinated.

The wide range of disciplines involved means that this work is quite challenging, but also important and urgent. Examples include :

Thermal insulation

Façade technologies

Passive solar techniques

Ventilation systems and air infiltration

Heating, ventilation and air-conditioning systems

Day-lighting and lighting systems

Building and system control

Automation

This holistic approach requires a common set of terms, definitions and symbols, which are provided in the newly published technical report ISO/TR 16344:2012, Energy performance of buildings - Common terms, definitions and symbols for the overall energy performance rating and certification.

The approach also requires :

Common rules on the assessment boundary of the building or building site

Calculation procedures for the interaction between energy uses (such as the way dissipation from lighting affects the building’s thermal balance)

Aggregation of the different energy uses

Conversion of the delivered gas or electricity and, for example, the produced electricity from photovoltaic or (micro-)combined heat and power, to the overall energy use of the building

This last requirement will be addressed by the future ISO 16346, Energy performance of buildings - Assessment of overall energy performance.

Finally, it is important to define a single numerical indicator that expresses overall energy performance. This can be used as the basis for classification on an energy performance certificate and/or for judging compliance against minimum requirements in building regulations. That is the job of the future ISO 16343, Energy performance of buildings - Methods for expressing energy performance and for energy certification of buildings.

The JWG has also started work on a standard for addressing the indoor environmental conditions assumed in energy performance calculations.

Especially when addressing the energy performance of nearly zero-energy buildings, many specific technologies need to be included in the overall calculation procedures such as :

High-performance thermal insulation materials

Thermal solar systems

Photovoltaic systems

Combined heat and power

Ventilation heat recovery

Active façades

And micro-combined heat and power

A spin-off from these key energy performance items currently under development is ISO 12655, Energy performance of buildings - Presentation of measured energy use of buildings. The standard will provide a methodology that will serve as a common basis to unify the collected data of measured building energy use, therefore facilitating parallel analytical comparisons.

ISO 12655 will maximize consistency with the other standards discussed here as another step towards harmonization.

Complex operation

Since modern commercial buildings have rather complex systems for heating and cooling, it is important to define the way energy goes through the building and how it is controlled.

Building energy management systems (BEMSs) are supposed to provide data on the performance of building technical systems. However, to carry out quality control of a building’s energy performance, it is necessary to integrate data from standards (requirements), BEMSs, measurements and building documentation. Existing standards do not yet cover these demands. One example is hydraulic systems, where performance is greatly influenced by the use of new components such as frequency-controlled pumps, dynamic pressure balance valves and constant pressure control valves. A new proposal is being prepared to deal with this issue within the JWG.

Road ahead

Although much progress has already been made in providing the tools to help the building industry ensure sustainable buildings, the end of the road has not yet been reached. ISO must be ready to respond to rapidly evolving technology, and emerging global challenges that meet the needs of today and of the future.

About the authors

Dick (H.A.L.) van Dijk, of the Netherlands-based research organization TNO, is also Co-Convenor of JWG of ISO/TC 205 and ISO/TC 163.

Prof. Dr. Essam E. Khalil, of Cairo University, Egypt, is also Co-Convenor of JWG of ISO/TC 205 and ISO/TC 163.

Egil Öfverholm, of the Swedish Energy Agency, is also Chair of ISO/TC 163.

Jonas Santesson, of SIS (ISO member for Sweden), is also Secretary of ISO/TC 163.

Stephen Turner is Chairman of Stephen Turner Inc. and Chair of ISO/TC 205.