The promise of greater workplace productivity can be even more alluring to companies than a few kilowatts saved by streamlining a building's energy efficiency. Happily, says commercial property and energy consultant Andrew Cooper, the two can go hand in hand.
18 June 2015 | By Andrew Cooper
The primary function of an office is to provide employees with the right environment and the tools they need to do their jobs.
Therefore its design should enhance productivity, which usually means (at the very least) maintaining an employee's physical and mental health. In addition, a good design should be energy-efficient and promote a reduction of waste.
Yet it is surprising how often designers chasing energy efficiency seem to forget about employee health and productivity.
We've all worked in an office where the temperature seems to swim from suffocatingly hot to freezing cold. Or where the light reflects off the screens or windows and causes a morning or afternoon of squinting at computer screens. At the worst end of the spectrum it can create sick building syndrome - often linked to poor indoor air quality.
Designers and operators including facilities managers should not disaggregate energy efficiency and staff productivity as the two are closely related and the rewards from improving productivity are potentially far greater than those from energy efficiency.
It is possible to achieve both. For example, we can follow the hierarchy of measures for energy/carbon reduction, as outlined in the Greater London Authority Plan, while still ensuring at all times that the effect of design on productivity is considered.
The London Plan
The London Plan is the overall strategic plan for London, and it sets out a fully integrated economic, environmental, transport and social framework for the development of the capital until 2036.
It introduced a hierarchical approach to energy efficiency and carbon emissions in planning and building design.
1. Be lean: use less energy
2. Be clean: supply energy efficiently
3. Be green: use renewable energy
This approach is also often adopted in sustainability feasibility studies outside of London, and these principles can be applied to new builds and to minor and major refurbishments.
Use less energy
- Try to exceed U-values (thermal performance) beyond any requirements under Building Regulations that cover both new builds and major refurbishments. This helps to prevent excessive fluctuations in temperature - saving energy and increasing comfort.
- Good window design is key to supporting productivity and saving energy. Ensure that window design maximises natural light but minimises excessive solar gain and glare. For existing buildings, modern window films can improve both U-values and g-values (the solar energy transmittance of glass) at a fraction of the price of new windows.
- Use high-efficiency lighting systems such as LED with photoelectric dimming control and motion sensors where appropriate. Consider the colour rendering of artificial lighting to replicate as closely as possible natural light. Again, ensure that any artificial lighting does not introduce glare: consider lower levels of ambient light (lux levels) with localised task lighting to empower occupiers (also shown to reduce energy). People who suffer from migraines, in particular, are affected by glare from luminaires and the use of high-frequency control gear and avoiding LEDs with poor quality drivers is recommended.
- Maximise the penetration of fresh air into the building to ensure that CIBSE guidelines on ventilation are adhered to. High levels of carbon dioxide (CO2) and VOCs (volatile organic compounds) can affect both productivity and health. For mechanical ventilation systems use heat recovery devices and ensure that specific fan power levels are better than those recommended under Building Regulations.
- For existing buildings consider how occupational requirements have changed since construction. Has occupational density increased and, if so, are the ventilation systems providing sufficient ventilation to ensure that average carbon dioxide levels remain below the CIBSE recommended 1,000 parts per million?
- Building engineering services and renewable energy systems should be properly commissioned so they work as per the design expectations.
- In addition to the normal building operation and maintenance manuals, building log books such as CIBSE TM31 should be prepared so that users understand how systems are intended to work, and what actions they can take to influence energy consumption and associated emissions from the building.
Supply energy efficiently
- Once demand for energy has been minimised, investigate if it possible to use low-carbon heat distribution networks. Using these sources of energy can help not only reduce CO2 emissions, but other types of emissions such as nitrogen oxides (NOx), all of which are considered pollutants and can contribute towards health problems.
- If it is not possible to use such networks, investigate the feasibility of onsite CHP or other low-carbon heat sources.
Use renewable energy
- Use of low or zero-carbon (LZC) technologies such as photovoltaic (PV) panels can help to improve energy efficiency, reduce emissions and even generate separate income streams. But these should only be considered after other measures that support energy efficiency have been exhausted.
Use post-occupancy evaluation
- Ensure that design aspirations are being met through operation. Building services should be seasonally recommissioned and analysed to ensure that their performance meets the design expectations.
- Periodic energy audits should be undertaken to include localised CO2 readings. Benchmarks should be developed to make sure that operational energy performance meets design expectations.
- Engage with occupiers to understand building performance from the perspective of building users. Are they happy? Make certain that interviews include a variety of occupiers from secretaries to C-grade staff.
FM and realising design
The FM should be consulted from the design stages through to commissioning. The gap between design expectations and operational realities is often such that if buildings were planes many would be falling out of the sky. It is possible to deliver efficient and productive workplaces, and who better to help plan and realise this balance this than those on the ground?
The conversation around energy efficiency is evolving. Organisations such as ASHRAE (the American Society of Heating, Refrigerating, and Air-Conditioning Engineers) have been highlighting that the energy-efficiency debate has been at the expense of indoor air quality.
Indeed, many clients will consider that the guarantee of better workplace productivity is more of an incentive than a few kilowatts saved.