1. Ventilation solutions for overheating corridors in apartment buildings

2. A brief history of Colt A private company founded in 1931
I J O’Hea OBE ( )
2012 Group turnover £151 million
Manufactures in the UK, Holland, Germany, Saudi Arabia, China and Brazil
I J O’Hea, Colt Founder

3. Current UK Business markets
Smoke Control
Solar Shading
Natural Ventilation
Louvre
Environmental Comfort Control
By investing in innovation, products, services and people, Colt International has established itself as an international leader in the fields of:
Smoke Control
Solar Shading
Natural Ventilation
Louvre
Environmental Comfort Control (HVAC)
Air Handling Systems

4. The quest for energy efficiency (ADL and BREAAM) has led to very good sealing and insulation in residential buildings and an increase in district heating schemes.
This has unintended consequences for stair lobbies, corridors and entrance halls, which tend to overheat, resulting in unpleasant conditions for residents.
Caspian Wharf, a Berkley Homes development, uses a district heating system and therefore overheating in the common corridors was a concern for the design team.

5. District heating systems distribute hot water to apartments 24 hours a day via insulated pipe work in the corridor ceiling voids.
Even with good insulation, enough heat is emitted to cause overheating in the corridors below.

6. 24/7 heat gains, per corridor:
Lighting Gains – 3W/m²
District Heating Gains - 10W/m²
Mechanical Riser – 204W
Comms. Riser – 150W
Based on 38m² foot print = TOTAL estimated heat load, per corridor 850W

7. Q: What can you do to avoid heat building up in these common areas?
A: Use the existing smoke control system for day-to-day ventilation.
The simple solution is to use the ventilation equipment which is already providing smoke control to these areas.
Natural or mechanical smoke ventilation systems may be adapted for day-to-day ventilation use.
Conclusions

8. Q: Will you require additional equipment or modifications?
A:The answer is dictated by how much temperature control you want
If your building has a multiple shaft smoke control system, it can readily be configured to provide day-to-day ventilation with minimal additions.
If the building has a single shaft system, you will need inlet air. You could provide it from the stair, using a weathered roof smoke vent. In this case, you will need fire rated smoke dampers between the stair and the corridor.
You will need to consider fan noise, as noise levels considered acceptable for emergency use will not be acceptable for day-to-day ventilation use.
Conclusions

9. Day-to-day Ventilation for Apartment Buildings: AOV Systems
Environmental Control Requirements – Natural AOV
AOV can be used for day-to-day ventilation, but:
Ventilation is single sided, has no separate inlet, has poor temperature control
Is lobby geometry and vent location suitable?
Potential for hold open devices on cross corridor doors for through flow?
Consider finger trapping
Control requirements: Wind, Rain..

10. Day-to-day Ventilation for Apartment Buildings: Natural Shaft Systems
Environmental Control Requirements – Natural Shafts
Natural shafts can be used for environmental ventilation, but:
There is no permanent air inlet unless specially provided
Is lobby geometry and vent location suitable?
Risk of cross contamination between floors
Motorised doors have issues with finger trapping and access to the shaft
Control requirements
Rain Sensor?

11. Multiple Shaft Smoke Control System
Supply
Extract
Corridor Smoke Damper & Grille for inlet/exhaust
Conclusions
Smoke Extract Fans for supply/exhaust

12. + + + Multiple Shaft Smoke Control System – additional requirements
Corridor Temperature Sensor +
Variable Speed Drive for Extract/Supply Fans +
Noise Attenuation for Smoke Extract Fans +
Conclusions

13. Single Shaft Smoke Control System
Supply
Extract
Corridor Smoke Damper & Grille for exhaust
Conclusions
Smoke Extract Fans for exhaust
Weathered AOV for supply air at head of staircase

14. + + + + + Single Shaft Smoke Control System – additional requirements
Corridor Temperature Sensor
Variable Speed Drive for Extract/Supply Fans + +
Standard AOV +
Ceiling Grilles
Fire Damper Between Stair & Corridor + +
Conclusions
Weathered AOV
Noise Attenuation for Smoke Extract Fans

15. D-t-d damper above ceiling?
Multiple shaft systems
Smoke damper
D-t-d damper above ceiling?
With this system, additional day to day ventilation dampers above the ceiling are necessary – to balance the air flow (allowing multiple floors to be ventilated simultaneously) and to ventilate the ceiling void (therefore dealing with the majority of the heat load at source).
Conclusions

16. More critical on ambient air systems:
Control Options
More critical on ambient air systems:
Cyclical Control
On activation, a limited number of floors (typically 3 to 4) will ventilate for a defined period, before shutting down and activating the next set of floors
Limited benefit
No balancing required
Smaller airflow rates/lower noise
High damper usage
Low turnaround on taller buildings
2. Constant Control
All floors can be ventilated simultaneously.
Improved performance
Balancing required
Higher airflow rate will almost certainly need attenuation
Higher energy consumption
Conclusions

17. Details that count - Fans
Environmental Control Requirements – Mechanical Shafts
Details that count - Fans
Dual purpose smoke extract fans can be used, but:
High tip clearance means low efficiency – high energy bills
Smoke fans are generally noisy
Future energy use restrictions from Europe may prohibit dual purpose fans on the basis of efficiency limits.
Consider smaller secondary fans?

18. Don’t expect CIBSE levels of accuracy (temperature or airflow)
The solutions described up to now provide a nominal amount of ventilation using outside air only. They will improve conditions in the corridors relative to no ventilation, but they may not provide comfortable conditions.
Manage expectations
Don’t expect CIBSE levels of accuracy (temperature or airflow)
Limited number of floors ventilated simultaneously
Systems will alleviate stuffiness and limit overheating
Corridors are transit spaces and don’t need close control (except in high value buildings with demanding residents)
Conclusions

19. Colt CoolShaft Corridor Evaporative Cooling System
So whilst a simple ventilation system based on supplying outside air alone will alleviate stuffiness and limit overheating, with the CoolShaft; we are able to reduce temperatures to below the outside ambient providing active cooling in the corridors.
Conclusions

20. Colt Corridor Coolstream
Colt’s CoolShaft Evaporative Cooling Ventilation System uses the cooling power of water to reduce the temperature, creating a more favourable environment in the corridors
Running and maintenance costs are extremely low and the warmer the outside air, the more efficient evaporative cooling becomes.
Conclusions

21. CoolShaft vs. basic outside air cooling
With CoolShaft
35ºC
Conclusions
With Outside Air

22. CFD Case Study
CFD model comparison to assess the expected temperatures within the corridors as a result of the given heat load.
Using ambient air as at the method of ventilation
Using CoolShaft
Studies are carried out using FloVent CFD for a typical level within a building.
The results shown represent a worst-case, steady-state condition.
Conclusions

23. Heat Source Ceiling Grilles (x4) Extract Point Supply Point
Conclusions

24. outside/ambient air 27.0ºC low-level 27.5ºC mid-level
28.0ºC high-level
Coolshaft
21.7ºC low-level
21.8ºC mid-level
22.4ºC high-level
Conclusions

25. Temperatures within corridors using outside/ambient air
Avg. ceiling void temperature 38ºC
Peak. ceiling void temperature 40ºC
Conclusions

26. Coolshaft Avg. ceiling void temperature 30ºC
Peak. ceiling void temperature 35ºC
Conclusions

27. Low cost of operation and maintenance
Colt CoolShaft
Offer a reduction in energy costs of up to 90% compared to conventional air conditioning
Low cost of operation and maintenance
Free from refrigerants, no F gas compliance
Integrated water quality system, simple technology
VDI 6022 certification for water hygiene
Filtered air supply (G4 & F7 filter options available)
Conclusions

28. Next Step – Air conditioning
Higher costs – both capital and operating
Introducing refrigerant and management issues
Space
Better temperature control
Conclusions

29. Questions?