The Renson Headquarters
The RENSONHeadquarters
Building
presentation
Renovation issue
Building concept
Indoor Air
Quality
Summer
Comfort
Monitoring
results
Major findings
More
information...
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building”
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Building presentation (1…)
The RENSONHeadquarters

Building
presentation

Renovation issue

Building concept
Indoor Air
Quality
Summer
Comfort


Monitoring
results
Major findings
More
information...
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building”
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The Renson company produces components for natural ventilation
Headquarters are situated in industrial zone along a busy road
Floor area: 1.350 m²
Two storey building - prefabricated concrete elements
Building façades
 rear side of building: connected to production hall
 front façade:
– along busy road
– south-west oriented
– considerable net surface of glazing (25%)
Building presentation (2|)
The RENSONHeadquarters
Building
presentation
N
Production hall
Offices
Renovation issue
Building concept
Indoor Air
Quality
Summer
Comfort
Monitoring
results
first floor
drawing
room
meeting meeting
room room
office 1 office 2 office 3 office 4 office 5 office 6 office 7
Major findings
ground floor
landscape office
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45m
reception &
show room
15m
More
information...
office 8
The renovation issue
The RENSONHeadquarters

1. THERMAL COMFORT:

Building
presentation
Due to the large glazing surfaces in the front façade there were serious
problems of overheating in summertime
Renovation issue
Building concept

Indoor Air
Quality
Summer
Comfort
Monitoring
results
2. INDOOR AIR QUALITY:

Before renovation
production
hall
Major findings
More
information...

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Before the renovation the ventilation system consists only of adjustable
trickle ventilators above the windows.
It is clear that the performances of this system depend on the wind
pressure on the front façade. As the wind pressure fluctuate strongly,
also the air flows (energy losses) and the indoor air quality
fluctuates strongly.
The building concept (1…)
The RENSONHeadquarters

Building
presentation
Renovation issue
Building concept
Indoor Air
Quality
Summer
Comfort
In 1997 the idea arose of a thorough renovation to tackle the
problems of:

overheating

fluctuating air flows
(see Chapter ‘Renovation issue’)

Monitoring
results
Major findings
More
information...
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A detailed study of the renovation was carried out by the BBRI to
evaluate different renovation solutions:

type of solar shading

possibilities and effect of intensive night ventilation

a new ventilation system based on natural supply and mechanical
exhaust
The building concept (2…)
Indoor Air Quality
The RENSONHeadquarters
Building
presentation

To improve the stability of the air flows a system of natural supply
& mechanical extraction was installed
 Advantages:
Renovation issue

Building concept
Indoor Air
Quality
Summer
Comfort


constant air flow (and IAQ) during office hours
adapted air flow in meeting rooms
reduced air flows (and ventilation losses) outside office hours
first floor
After renovation
Monitoring
results
Major findings
production
hal
More
information...
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meeting
room
Natural air supply:
existing adjustable
trickle ventilators
above windows
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Mechanical
extraction:
ductwork in
false ceiling
ground floor
landscape office
reception &
show room
Building concept (3…)
Thermal summer comfort
The RENSONHeadquarters
Building
presentation

The following strategy was followed to improve summer
comfort:
Renovation issue
Building concept
Indoor Air
Quality
Summer
Comfort
Monitoring
results
GLOBAL STRATEGY for
thermal comfort under
summer conditions
REDUCTION of DIRECT
SOLAR GAINS:
Major findings
FREE-COOLING &
STORAGE:
night ventilation &
thermal mass
More
information...
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Overhangs &
Night ventilation:
selective glazing
partly natural partly mechanical
Building concept (4…)
Thermal summer comfort
Reduction of solar heat gains
The RENSONHeadquarters
Building
presentation

Several shading devices were evaluated using thermal simulations
Finally a combination of overhangs + selective glazing was chosen

Renovation issue
40
Building concept
Indoor Air
Quality
Summer
Comfort
Major findings
More
information...
Selective glazing
Horizontal overhang
30
temperature (°C)
Monitoring
results
External screen
35
25
20
15
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Reference
model
External temperature
10
8/06/96
0:08
NatVent
8/06/96
12:08
9/06/96
0:08
9/06/96 10/06/96 10/06/96 11/06/96 11/06/96 12/06/96 12/06/96 13/06/96 13/06/96 14/06/96 14/06/96
12:08
0:08
12:08
0:08
12:08
0:08
12:08
0:08
12:08
0:08
12:08
time (days)
Building concept (5…)
Thermal summer comfort
The RENSONHeadquarters
Building
presentation
Reduction of solar heat gains

Selective glazing:

HEAT: This special type of glazing has a
low solar transmission (g-value = 34%
instead of 77% for double glazing).

LIGHT: However due to a special coating
technology still 66% of the light is still
transmitted.
Renovation issue
Building concept
Indoor Air
Quality
Summer
Comfort
Monitoring
results
Major findings
More
information...
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
Overhangs:

The performances of the overhangs
depend on the orientation of the façade
and the position of the sun (see chart - next
slide)
Building concept (6…)
Thermal summer comfort
Performance of overhang for south-west façade
90%
0.8 m
50%
0.6 m
40%
30%
20%
WINTER: Little shading
- low position of sun
10%
NatVent
25-Jan
26-Dec
26-Nov
27-Oct
27-Sep
30-Jan
0%
31-Dec
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28-Aug
More
information...
1.2 m
1.0 m
29-Jul
Major findings
1.4 m
60%
29-Jun
Monitoring
results
70%
30-May
Indoor Air
Quality
Summer
Comfort
Average shading on window (%)
Building concept
Depth of
overhang
SUMMER: Much
shading - high
position of sun
80%
30-Apr
Renovation issue
31-Mar
Building
presentation
Reduction of solar heat gains
1-Mar
The RENSONHeadquarters
Building concept (7…)
Thermal summer comfort
Night ventilation
The RENSONHeadquarters
Building
presentation
Night ventilation:
Renovation issue
Building concept
Indoor Air
Quality
Summer
Comfort

Supply: natural supply through
large grilles in front façade

Monitoring
results
Extraction:

Major findings
More
information...
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
Natural extraction for offices
on ground floor: based on
stack effect of chimney on
the roof
Mechanical extraction (fan)
for offices on first floor
( There were practical
problems to install a
chimney)...
Building concept (8...)
Thermal summer comfort
Night ventilation
The RENSONHeadquarters
Building
presentation
Renovation issue
Building concept
Large burglar-proof
ventilation grille for
intensive night
ventilation
Night ventilation
of first floor
Indoor Air
Quality
Summer
Comfort
Monitoring
results
Major findings
More
information...
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fan
production
hall
Ventilation of
ground floor
chimney
production
hall
Building concept (8...)
Thermal summer comfort
Night ventilation
The RENSONHeadquarters
Building
presentation
Renovation issue
Night ventilation
of first floor
chimney
fan
Building concept
production
hall
Indoor Air
Quality
Summer
Comfort
Monitoring
results
Major findings
More
information...
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Ventilation of
ground floor
chimney
production
hall
Chimney - internal view
& control panel
Building concept (9|)
Thermal summer comfort
Night ventilation - remark
The RENSONHeadquarters
Building
presentation

Renovation issue
Building concept
Indoor Air
Quality
Summer
Comfort
Monitoring
results
Major findings
More
information...
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The potential for night ventilation in
this office will be limited because
the low accessibility of the thermal
mass. The offices have:



false ceilings
carpeted floors
light internal walls
Monitoring results (1…)
The RENSONHeadquarters

Building
presentation
Several parameters were monitored during
the summer of ‘97: temperatures, air changes,
CO2 -conc.,...
Renovation issue
Building concept

Indoor Air
Quality
Summer
Comfort
Monitoring
results
Major findings
More
information...
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Renovation had not been completed before
the monitoring began:


Solar shading (selective glazing & overhangs)
were not yet installed
Night ventilation
– large supply grilles were installed
– extraction chimney & fan not yet
installed: (building was ventilated by
opening doors to the production hall)
Monitoring results (2|)
Summer ‘97
The RENSONHeadquarters
Building
presentation
Renovation issue
Due to the lack of solar shading (renovation not yet completed)  The
internal temperatures are too high: >30°C
 For more results: see the detailed Monitoring Report (see Chapter: “More
information…”
35

Building concept
Monitoring
results
Major findings
More
information...
30
25
temperature (°C)
Indoor Air
Quality
Summer
Comfort
20
15
Still: More about night
ventilation: x ACH / working
thermal exterior
mass...
10
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office 4
office 3
office 1&2
5
1/8
2/8
3/8
4/8
5/8
6/8
7/8
8/8
9/8
10/8
time (days)
11/8
12/8
13/8
14/8
15/8
16/8
17/8
18/8
Major Findingds
The RENSONHeadquarters
Building
presentation
Renovation issue

The monitoring results show that there is a need for solar shading
(as foreseen in the total renovation plan)
 As the renovation had not been completed before the monitoring
began one can not draw conclusions on the concept.
Building concept
Indoor Air
Quality
Summer
Comfort

There were specific problems with the renovation of this building

It was difficult to ventilate all the offices at night by natural ventilation
(practical problems to install second chimney  replaced by fan)

The building has a low accessibility of the thermal mass
Monitoring
results
Major findings
More
information...
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More information...
The RENSONHeadquarters
Building
presentation
Renovation issue
Building concept
Indoor Air
Quality
Summer
Comfort
Monitoring
results
Find more information on the PROBE building in the following documents:
\Reports \Monitoring Reports \Summary Reports\be3summ.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\be3det.pdf
 detailed reports of all 19 monitoring campaigns (20p./campaign)
 contents: monitoring set up - analysis of results - conclusions
Major findings
More
information...
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building”
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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