1. Underfloor ventilation to enhance thermal comfortPresented toThe Green Buildings Congress Hyderabad, September 2009 Author: Glan Blake Thomas C Eng MCIBSE Member British Council for Offices International Committee

2. Improved Construction standards offerimproved staff performance

3. 3 The British Council for Offices champions high quality office space in the UK

4. Efficient office spaces incorporate flexible working and practical meeting areas

5. Greater efficiency is a major driver in European office building design

6. Raised floors are commonplace in office buildings

7. The evolution of underfloor air distribution

8. Underfloor Air Distribution is widely accepted Indoor Air Quality is high

9. Benefits of going underfloor From this..... To this.....

10. Using the underfloor void for air distribution may be a useful tool in reducing the height of a building

11. Height saving in new buildings reduces cost in both fiscal terms and embodied energy consumption This 87 storey, Cheung Kong building in Hong Kong uses underfloor air distribution. Over 35m (10 floors) was saved in the height of construction whilst still retaining the same ceiling height as in the original design using overhead air distribution.

12. Thermal gain and therefore cooling loads are dramatically reduced

14. Maintenance costs(corrective, not planned costs)

15. Maintenance costs(preventive, planned costs)

17. Reconfiguration is easy and less wasteful

18. Systems may be detached entirely from the building fabric

19. So....how does it work? Underfloor air may be supplied either centrally or on a zonal basis Zonal Air Handling Units Central Plant The Center, Hong Kong

20. Underfloor supply is often extracted at high level

21. Floor return is an option too

22. Air is filtered and cleaned using a variety of methods

23. Air may be introduced by fan power so reducing underfloor pressures TEMPERATURE VELOCITY

24. Air may be introduced very locally

25. Or very commonly by Displacement Swirl Grilles

26. VAV systems are popular in Europe

27. The next generation of VAV

28. IAQ in Underfloor Systems Underfloor supply/high level return High level supply/high level return

29. Study of IAQ in Underfloor & Overhead Systems Shin-Ichi Tanabe is a professor in the Department of Architecture, Waseda University, Tokyo, Japan.

30. Hong Kong University study of Underfloor Air

31. Swedish Clinic for Occupational Medicine * * * * * * *

32. Underfloor air: may be used in a wide variety of applications for cooling and/or heating. is suitable for both new build and refurbishment applications is suitable for floor voids as low as 150mm offers increased headroom in refurbishments saves up to 15% on the height of new buildings allows freedom in design through the absence of overhead services saves 90% in churn costs over ceiling systems through ease of reconfiguration offers energy savings through zonal control, reduced fan power and free cooling may be used with re-usable energy applications can assist in achieving improved LEED or BREEAM scores OPTIMISES INDOOR CLIMATE CONDITIONS SO AS TO MAXIMISE PRODUCTIVITY

33. As Engineers, we must not stay quiet, we must search for new ways and we must listen to others

34. Remember, the World’s resources are not inherited from our ancestors, but borrowed from our children Sustainability at Work www.flexiblespace.com