Energy efficient entrances to buildings can be achieved by correctly fitting and maintaining an effective air barrier. CIBSE approved CPD presentations available to consultants and architects.

1. Air Curtain Presentation

2. Air Curtain Fundamentals * Usually mounted over doorway, alternatively at sides * Reduces outside air entering building * Creates a warm air stream * Reduces mixing of inside / outside climates * Energy saving device * Improves internal environment * Can be installed in different applications

3. Air Curtain Fundamentals * Usually mounted over doorway, alternatively at sides * Reduces outside air entering building * Creates a warm air stream * Reduces mixing of inside / outside climates * Energy saving device * Improves internal environment * Can be installed in different applications

4. Air Curtain Fundamentals * Usually mounted over doorway, alternatively at sides * Reduces outside air entering building * Creates a warm air stream * Reduces mixing of inside / outside climates * Energy saving device * Improves internal environment * Can be installed in different applications

5. Air Curtain Fundamentals * Usually mounted over doorway, alternatively at sides * Reduces outside air entering building * Creates a warm air stream * Reduces mixing of inside / outside climates * Energy saving device * Improves internal environment * Can be installed in different applications

6. Air Curtain Science * Most efficient leaving air velocity 6.5~7.5 m/s * Optimum leaving air temperature 36~38ºC. * Achieve laminar flow of air stream * Designed to work with ambient air temperature of between 16~20ºC * Not a barrier, the air stream tempers incoming infiltration * Can be used throughout Summer & Winter

7. Factors Affecting Air Curtain Performance * Building design * Building leakage / extract rates * Surrounding geography * Prevailing weather conditions * Installation of air curtain * Leaving air temperature/velocity * Method of control

8. Factors Affecting Air Curtain Performance * Building design * Building leakage / extract rates * Surrounding geography * Prevailing weather conditions * Installation of air curtain * Leaving air temperature/velocity * Method of control

9. Air Curtain Pitfalls * Installed too high. * Leaving air temperature too low * Not covering full width of door * Used as a primary heat source * Leaving air temperature too high * Inadequate method of control * Incorrectly installed (i.e. too far away from door opening)

10. Correct Installation * Cover full width of door opening * Outlet grille as close as possible to top of door * Install within correct mounting height * Controls method * Consider aesthetics / environment * Units can be mounted vertically and horizontally Air curtain not covering full width, air bypass at sides Plan view showing cold air bypass at sides

11. Scenarios * Air Curtain Operating Building leakage 5m3/h/m2 Minimal infiltration Good climate separation * Air Curtain Operating Building leakage rate increased 20m3/h/m2 Infiltration is at slightly higher level. Climates still well separated * Air Curtain Switched Off Building leakage rate 20m3/h/m2 Infiltration rate high, cold spots around doorway. Climates mixing, thus entrance cooling. Temperature profile very uneven

12. BSRIA Study Findings (BSRIA report 77710/1) * Correct installation is vital. * Outlet grille design is important. * Building design affects the performance. * Building leakage greatly affects performance. * Too high leaving temperature affects air stream. * If outside air entering the door way exceeds 3m/s (13 MPH) the warm air stream begins to breaks down.

13. Controls * Manual / stand alone operation * Interface with building management systems * Door switch / time clocks * Thermostatic control * External sensors * Intelligent controllers ~ latest technology

14. “Enetec” Energy Saving Controller * Enetec intelligent controller (tested by BSRIA) * Monitors external and internal temperature, modulates heat output * Heater output regulated proportionally, instead of staging * Savings of between 30 & 60% have been recorded. (compared to standard air curtain control) * Units can be linked in master / slave scenario * Links into BMS

15. Conclusions * Take into account influencing factors * Size units correctly * Consider control options * Ensure correct installation. * Do not be influenced by others

16. Projects Sports Centre, Bath. Vertical circular door curtains

17. Projects Shopping Centre, Basingstoke. 380mm dia circular door curtains

18. Projects Cargo Village, Heathrow. Vertical Air Barriers

19. Projects GLA Building, London. Vertical circular door curtains

20. Projects Alpha Matrix, Swansea. Vertical Elliptical door curtains