Transcript No Slide Title

The Canning Crescent Centre
The Canning
Crescent Centre
Presentation
of the building
Building
concept
Monitoring
campaigns
Monitoring
results
Major
findings
More
information...
Back to
“Select a
building”
NatVent
Building presentation (1...)
The Canning
Crescent Centre


Presentation
of the building


Building
concept
Monitoring
campaigns
The Canning Crescent Centre is a community day-care centre completed in
1994 at a cost of £1.3 million. It is an L-shaped two-storey building with a
gross floor area of 1350 m2. It is located on a busy high street in Wood
Green, an urban area of London where air pollution and noise levels are
high.

It is a high thermal mass construction comprising a steel frame with exposed
brick walls and a concrete ground floor ceiling.
The south west side of the building faces the busy high street where air and
noise pollution is high.
The north east side faces a ‘clean’ enclosed garden courtyard and car park.
Major
findings

Back to
“Select a
building”
Architects: MacCormac Jamieson, Prichard, UK
Building Services Engineer: Atelier One, UK
Research team monitoring the building: Dr Vina Kukadia, James Pike, Martin
White, Building Research Establishment, UK

Monitoring
results
More
information...
Building information:

NatVent
Building presentation (2|)
The Canning
Crescent Centre
Presentation
of the building
Plan view of ground
and first floor
Building
concept
Monitoring
campaigns
Monitoring
results
Major
findings
More
information...
Back to
“Select a
building”
NatVent
The Canning Crescent
Centre from the
courtyard car park
Building concept (1...)
Ventilation philosophy
The Canning
Crescent Centre


Presentation
of the building

Building
concept
Monitoring
campaigns

low budget so there is no mechanical ventilation
the need to protect patient confidentiality from pedestrians in the high street
overhearing conversations
the need to prevent the ingress of air pollution and noise from the high street

Diaphragm cross walls used to provide a series of individual chimneys
which allow air to be drawn through the building by wind and buoyancy
forces.

Fresh air for the whole building comes exclusively from the ‘clean’
courtyard side.

Window opening along the front of the building facing the high street is
discouraged.
Monitoring
results
Major
findings
Design of building and ventilation strategy is based on
More
information...
Back to
“Select a
building”
NatVent
Building concept (2...)
Ventilation philosophy
The Canning
Crescent Centre
Presentation
of the building
Building
concept
Monitoring
campaigns
Rooflight
Monitoring
results
Series of individual
chimneys
Major
findings
More
information...
Exhaust
air
Exhaust
air
Fresh
air intake
Back to
“Select a
building”
Garden
Courtyard
NatVent
High Street
Building concept (3...)
Ventilation system - room facing courtyard
The Canning
Crescent Centre
Presentation
of the building
Building
concept
Air extract grille at
high level
Openable windows with
trickle ventilators
Monitoring
campaigns

Air supply is purely by
openable windows and trickle
ventilators located in the
window frames.

Air exhaust from each room
is via a high level wooden
extract grille and its own
exhaust stack.
Monitoring
results
Major
findings
More
information...
Back to
“Select a
building”
NatVent
Room facing the courtyard
Building concept (4...)
Ventilation system - room facing courtyard
The Canning
Crescent Centre
Presentation
of the building
Building
concept
Monitoring
campaigns
Fresh air
intake on
external
wall
facing
courtyard
Air supply and extract grille
in room facing high street
High level air
extract grille
Monitoring
results
Major
findings
More
information...
Low level air
supply grille

Back to
“Select a
building”

NatVent
Air is supplied through openings in
the external courtyard facing wall
Air is then ducted through the footings
of the building to low level wooden
supply grilles.
Building concept (4|)
Ventilation system - Air exhaust stack
The Canning
Crescent Centre
Presentation
of the building
Building
concept
Monitoring
campaigns
Monitoring
results
Low pressure zone
induced below aerofoil,
drawing air up chimney
(Bernoulli effect)
Air flow across chimney
Adjustable air
flow damper
Solar ‘accelerator’
Major
findings
More
information...
Back to
“Select a
building”

Adjustable air flowdamper in the
stacks controls the air change rate
in each room

Dampers in the stack are controlled
manually and set centrally to
Damper actuator:

Air from internal spaces
exits at high levels
NatVent

Fully open in the summer to aid
cooling
Almost closed in the winter to
provide reduced flow rates sufficient
to maintain optimum indoor air
quality and minimise energy loss
Building concept (5|)
Ventilation strategy
The Canning
Crescent Centre

Winter ventilation strategy

Presentation
of the building

Building
concept
All dampers set in an almost closed position to provide background air for
ventilation and removal of carbon dioxide.
Local control of dampers allows increased rates of air flow in individual offices
when required.
Monitoring
campaigns
Monitoring
results

Summer ventilation strategy

Major
findings

More
information...

Back to
“Select a
building”
NatVent
Dampers in the stacks are set in the fully open position to maximise air flow
rates to cool the thermal mass of the building.
Automatic roof lights open up to purge the heat from the building during the
night time.
Solar heated double glazed panels at the top are intended to provide increased
buoyancy and hence extract flow rate.
Monitoring campaign (1...)
The Canning
Crescent Centre

Aims of monitoring campaign:

Presentation
of the building
– Thermal comfort
– Removal of carbon dioxide
– Minimising ingress of external pollution into the building
Building
concept

Monitoring
campaigns
Monitoring
results
To determine the performance of the ventilation strategy all year round in
terms of

Major
findings
More
information...
Monitoring was carried out in



NatVent
four offices
– Two facing the high street, ground and first floor.
– Two facing the courtyard, ground and first floor.

Back to
“Select a
building”
To provide recommendations for improvement of ventilation system if
necessary
corridor
high street
seminar room
Monitoring campaign (2...)
Location of measurements
The Canning
Crescent Centre
Presentation
of the building
Temperature sensor
Noise meter
Location of measurements
Plan view
T
4
Sample tube
Building
concept
Dosing tube
Monitoring
campaigns
T
3
A
Monitoring
results
External sample point
Hot-wire anemometer
Major
findings
More
information...
N
Courtyard
Back to
“Select a
building”
NatVent
Seminar room
Busy High Street
Monitoring campaign (3|)
different campaigns
The Canning
Crescent Centre

Winter monitoring

Presentation
of the building
Indoor Air Quality and other
measurements

– Air change rates
– Local air velocity
– Temperature
Building
concept

Monitoring
campaigns
Monitoring
results
Monitoring carried out over 1
week in March 1997



Major
findings
More
information...
Summer monitoring

Monitoring carried out over 1
week in July1997
– Air change rates
– Temperature


Back to
“Select a
building”
NatVent
–
–
–
–
Internal mean radiant
External air
– Humidity
– Carbon dioxide
Internal mean radiant
External air
– Humidity
– Carbon dioxide
Monitoring carried out over 1
week in March 1997


Carbon monoxide
Nitrogen oxides
Sulphur dioxide
Noise
Air flow rate through inlet grille
Occupant questionnaire and
interviews
Monitoring results (1…) - winter
The Canning
Crescent Centre
Presentation
of the building
Building
concept

Results for office 3 - good representation of all monitored
offices

Ventilation rates of 1 to 2 air changes per hour (ach) were
obtained. Mean internal daily temperatures varied between 1725°C. This is slightly higher than a design temperature of 18°C.

Relative humidity levels varied between 40 to 60%.

Carbon dioxide levels increased in the presence of occupants
but reduced rapidly to background levels of 400 ppm in their
absence. This also occurred in summer.

Local air velocities averaged at 0.1 ms-1 (not shown)
Monitoring
campaigns
Monitoring
results
Major
findings
More
information...
Back to
“Select a
building”
NatVent
Monitoring results (2...) - winter
The fresh air supply is sufficient  The IAQ is acceptable: the CO2concentrations are below the limit of 1200 ppm.
Building
concept
Monitoring
campaigns
Monitoring
results
Major
findings
More
information...
Int. Temp (ºC), Ext.Temp (ºC),
Air Change Rate (ach)
Presentation
of the building
30
1.2
Tint.
25
1
20
0.8
15
0.6
Text.
10
0.4
CO2./1000
5
Air Change
Rate
0.2
0
0
14/03 12:00
15/03 12:00
16/03 12:00
17/03 12:00
18/03 12:00
19/03 12:00
20/03 12:00
Week between Fri 14 March 1997 and Fri 21 March 1997
Back to
“Select a
building”
NatVent
The air change rate is sometimes relatively high, when the office is not
occupied. This leads to unnecessary energy losses. This problem occurs
because the settings of the flow dampers are not clear to the occupants.
21/03 12:00
Carbon Dioxide/1000 (ppm),
Relative Humidity/100 (%)
The Canning
Crescent Centre
Monitoring results (3...) - summer
The Canning
Crescent Centre
Results for office 3 - good representation of all monitored offices
Presentation
of the building

Ventilation rates of about 2-3 ach were generally obtained; and
about 17 ach when the dampers in the stack were manually
opened for periods of one hour.
However the night ventilation strategy was not implemented. This
is mainly due to the fact that the settings of the flow dampers are
not clear to the occupants.
Major
findings

Mean internal daily temperatures varied between 17 to 27.5°C.
More
information...

The IAQ is acceptable: the CO2 -concentrations are below the limit
of 1200 ppm.
Building
concept
Monitoring
campaigns
Monitoring
results
Back to
“Select a
building”
NatVent
Monitoring results: see next slide… 
Monitoring results (4...) - summer
30
CO2 ./1000
Presentation
of the building
Monitoring
campaigns
Monitoring
results
Major
findings
More
information...
0.9
25
Int.Temp (ºC), Ext. Temp (ºC),
Air Change Rate (ach)
Building
concept
1
Text.
Tint.
0.8
0.7
20
0.6
15
0.5
0.4
10
Air Change
Rate
0.3
0.2
5
0.1
0
01/07 00:00
Back to
“Select a
building”
NatVent
0
02/07 00:00
03/07 00:00
04/07 00:00
05/07 00:00
06/07 00:00
Week between Tues 1 July 1997 and Mon 7 July 1997
07/07 00:00
08/07 00:00
Carbon Dioxide/1000 (ppm),
Relative Humidity/100 (%)
The Canning
Crescent Centre
Monitoring results (5...)
Indoor air quality
The Canning
Crescent Centre

Presentation
of the building
Building
concept
Monitoring
campaigns
Carbon monoxide (CO), nitrogen oxide (NO), nitrogen dioxide (NO2) and
sulphur dioxide (SO2 ) levels were well within recommended air quality
guidelines
Measured
gas
Measured
mean
concentrations
Monitoring
results
Major
findings
More
information...
Back to
“Select a
building”
NatVent
Recommended air quality guidelines
Expert
Panel on Air
Quality
Standards
World
Health
Organisation
European
Community
CO (ppm)
0.31
101
101
-
CO2 (ppm)
400
-
-
-
NO (ppb)
222
-
-
-
NO2 (ppb)
432
1502
801
1051
SO2 (ppb)
22
1003
1222
942
1
2
3
8-hour mean
1-hour mean
15-min mean
Monitoring results (6|)
Occupant questionnaires
The Canning
Crescent Centre

Occupants reactions were as follows:

Presentation
of the building

Building
concept

Monitoring
campaigns
Monitoring
results
Cold down draughts from the high level extract grilles were felt during the
winter; as a result the grilles were sealed with plastic film and cardboard.
Electrical fan heaters were used as auxiliary heat sources in the winter.
During the summer there was considerable overheating in the offices facing
the courtyard.
Extract grille covered with card
Major
findings
More
information...
Back to
“Select a
building”
NatVent
Findings & Improvements (1...)
The Canning
Crescent Centre

Issues and lessons learnt:

Presentation
of the building
Building
concept
– Master stack damper control labelling was unclear and resulted in the
wrong setting being applied during the summer period.
– Inadequate maintenance of dampers resulted in the dampers being ‘stuck’
in the closed position even in the summer.
– Dampers being leaky or ‘stuck’ in the open position resulted in cold down
draughts during the winter.
– High pressure losses in the stack may have contributed to reduced air
change rates.
Monitoring
campaigns
Monitoring
results
Major
findings
More
information...

Back to
“Select a
building”
NatVent
Summer-time comfort could be improved by a more effective
intensive night ventilation, which would cool down the thermal mass.
The ventilation system functions were ineffective due to several
reasons:
Summer-time comfort could also be improved by installing external
shading devices to reduce the solar gains through the windows.
Conclusions (2...)
The Canning
Crescent Centre

Suggested improvements:

Presentation
of the building

Building
concept

Monitoring
campaigns

Monitoring
results

Major
findings
More
information...

Conclusion:

Back to
“Select a
building”
NatVent
Removal of air flow dampers in each exhaust stack.
Replacement of inlet and outlet openings with conventional slide
control grilles.
Central damper settings should be clearly marked ‘open’ for the
summer and ‘closed’ for the winter.
To prevent cold down draughts, a small low-energy priming fan is
recommended.
In the design calculations all pressure drops need to be accounted
for.

Air intakes from the ‘clean’ garden courtyard side ensured that the
ingress of external pollution and noise was minimised.
….
Conclusions (3|)
The Canning
Crescent Centre

Presentation
of the building
Suggested improvements:


Building
concept

Monitoring
campaigns

Monitoring
results
...
Regular maintenance of the ventilation system and correct labelling of
the dampers are required to ensure correct operation.
All controls should be readily understood and be easy to operate by
maintenance staff, facilities managers and office staff.
The operation of the building can be substantially improved by
introducing the modifications suggested.
Major
findings
More
information...
Back to
“Select a
building”
NatVent
The BRE research team would like to express their thanks to

N Morris, M Osbourne and M Strachan from the Canning Crescent
Centre, UK

I Logan from MacCormac, Jamieson, Prichard

J Grace from Atelier One, UK

Martin Liddament from the Air Infiltration and Ventilation Centre, UK
More information...
The Canning
Crescent Centre
Presentation
of the building
Building
concept
Monitoring
campaigns
Monitoring
results
Major
findings
Find more information on the PROBE building in the following documents:
\Reports \Monitoring Reports \Summary Reports\gb2summ.pdf
 global presentation of the buildings (4p./building)
 contents: building description - ventilation strategy and technology winter and summer monitoring results - conclusions
\Reports \Monitoring Reports \Detailed Reports\gb2det.pdf
 detailed reports of all 19 monitoring campaigns (20p./campaign)
 contents: monitoring set up - analysis of results - conclusions
More
information...
Back to
“Select a
building”
NatVent
You can read and print pdf-files with the Acrobat® Reader
®3.0. Program. This program is free.
Download it from the Acrobat web site: www.adobe.com OR
run the installation file ar32e301(1).exe in the directory
\Installation