Note: Descriptions are shown in the official language in which they were submitted.
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Multi-storey Etuildin~ Facade Featurin~ a Facade-casin~ of Claddin~ Panels
The invention relates to a multi-storey building facade, featuring a facade casing, consisting
5 of cladding panels connected with the building wall and its window openings. The casing is
positioned spaced away from the building wall and consists of individual, essentially vertical
chambers; each chamber features an air-intake vent connected to the facade-casing through
which fresh air can enter into the chamber, and also in its upper part an air-exit vent through
which any air contained in the chamber can escape, whereby the allocated intake-and exit-
o vents of the same chamber are located in different stories of the building.
Back~round of the Invention
A facade-casing design according to European patent disclosure EP 0 415 201 A 2 permits
the quick and easy construction of facade casings made from pre-fabricated cladding panels,
such as glass, metal, natural rocks, and similar material, using only a small number of
mounting devices; details are explained later on.
The weight of the facade-elements is transferred by way of interlocking to the building wall,
preferably to the subsequent story. Similar facade constructions have been introduced in
German patent disclosure DE-U 92 08 752, and European patent disclosure EP 0 608 443 Bl .
However, these designs did not satisfactorily solve the problem of noise transmitted into the
interior of the building, e.g. the noise from the surrolln~ling.c and also the noise caused by the
ventilated faca.de-casing itself. Thermal considerations and the amount of energy used to heat
or to cool the building, are indicative for the need of an improved technology.
A multi-store~y building facade featuring the above characteristics has been described in
German patent disclosure DE 40 22 441 Cl. In this specification a facade-casing, consisting
of individual cladding panels is positioned in front of the actual facade. The created interior
space, which c ontains a system of canals and chambers installed over the entire height of the
building, faciliitates the ventilation of the facade and the rooms located behind it. The
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chambers are located in front of the window openings of the facade and feature vents for fresh
air-intake at the upper window rim whereby the exit-vents are situated slightly above these
vents. The exit-vents lead to the adjacent central canal, which features additional separate air-
intake vents, so that the entire fresh air supply entering through the air-intake vents is directed
5 through vertical canals covering the entire height of the building up to the roof-level. This
construction intends to utilize the heating created in the outer sheath of high-rise buildings, in
order to destroy the rising air and the developing air cylinders.
However, German patent disclosure DE 40 22 441 Cl, describes an the entire building and
o the flow patterns created by it. This construction cannot effect reproducible pressure
conditions in each individual chamber, since all chambers are connected with the central
canals through air-exit vents located in the upper parts of the chambers, and the entire facade
ventilation is controlled by these canals. Sweeping and pressure effects, to which the
building might be subjected due to ch:~nging wind-and temperature conditions, can cause
5 major over-currents and current linkages, which in turn will, due to the central air-exit vents
located in the roof-area, cause changed current conditions inside of the individual chambers
that are located in front of the window openings. Due to pressure conditions and especially
during adverse weather conditions, it cannot prevent exhausted air from flowing back out of
the vertical canals into the sideways located chambers, possibly reaching rooms inside of the
20 building. The facade discussed above has certain disadvantages in regards tothe achieved
noise-reduction. Since the chambers located in front of the windows are connected with each
other through 1he central canals, sound can also travel this way.
25 Summar,v of the Invention
An object of the invention is, to create a multi-storey building facade which is improved in
regards to air flow and noise reduction and which features a facade casing consisting of
cladding panels. The air-exit vent is positioned into the facade casing with the vertical
30 distance between the air-exit vent and air-intake vent in the lower part of the chamber
measuring more than one story.
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A facade designed in this way has an exactly defined air flow between building wall and
facade casing. While the minimum space between facade casing and wall measures 15 cm,
preferably between 20 and 40 cm, the interior space between casing and wall is divided into
5 individual chambers, whereby each chamber features in its lower part an air-intake vent,
modeled in the casing, through which fresh air from the inside can flow into the chamber.
Moreover, at least one air-exit vent is designed in the upper part of each chamber between
casing and building wall, through which the air can leave the chamber. In order to optimize
the air-flow, air-intake-and air-exit vents shall be located in a sufficient vertical distance from
o each other, e.gl. at least one story. The invention suggests especially to place the correlating
air-intake-and exit vents of one chamber in different stories of the building.
Due to the chamber-system located in front of the building wall which is subjected to a
natural air flow, the improved facade is featuring especially favorable thermal qualities.
5 During the colder seasons, the facade casing is exposed to the warming rays of the sun,
consequently heating the airflow behind it and reducing any loss of heat through the building
wall. During the warmer season, the air flowing through the chambers between the facade
casing and the building wall has a cooling effect, thereby is balancing the temperature
between the outside and the interior of the building.
Another advantage of the design, according to which the facade elements are situated in front
of the building wall, is the achieved sound proofing against environmental noises; this is
accomplished through the minimum distance between facade casing and building wall, as
suggested by the invention.
A special feature of this design is that the chambers are branching in their upper part into two
spaced exit-canals, with one exit-vent located at the level of each of these exit-canals. The
frontal view presents the individual chambers in a U- shape, which offers the advantage of a
large vertical distance between air-intake and air-exit vent, creating a temperature-drop, hence
30 an air flow within the chamber. Moreover, the two exit-canals branching from the chambers
offer definite technical advantages for the mounting of the individual elements to the building
wall. Also, there is a definite sonic decoupling effect between the elements of the facade-
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casing correlal:ed to the different stories; within the ventilated facade sound cannot travel
from one story to the next, and the tr~n~mi~sion of noise between two chambers can be
reduced, as well.
s Moreover, the invention provides for the positioning the exit-vents at the same level as the
window openings. It is also advantageous to design the chambers in such a way that the
canals are branching out through the lower bottom part of the correlated chamber above, so
that the exit-canals are located parallel to both sides of the respective chamber above. In this
case, the vertiical separating wall between the chamber and the exit-canal of the chamber
0 below can be iitted with sound-insulation material.
To further improve the facade-structure, the vertical separating wall between chamber and
exit-canal of the respective chamber below can function simultaneously as static connection
between facade casing and building wall. Hence, the vertical sel)dldlillg wall has two
s functions; it separates the interior space of two successive chambers and it also serves the
important static purpose of mounting the individual elements to the building wall.
Another feature of the improved design are mounting devices located at the outward rim of
the vertical separating wall, which fasten two elements positioned above each other. The
20 vertical separating wall may be designed as a metal box cont~ining sound insulating material.
This sound insulating material will reduce any noise which might be caused by the upward air
flow in the chambers.
Another feature of the improved invention is a fixed or moveable sun-breaker, which can be
2s installed either in front of or behind the facade-casing. If this device is placed in front of the
casing it could be designed as a slanting surface fitted to the mounting elements.
Finally the invention provides a the i'acade which includes devices for dispensing a pre-
determined amount of a fluid, such as water, onto the surface of the facade elements. On hot
30 days, this would effect an evaporative cooling on those elements, as the heated water
evaporates.
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Drawin~s
More advantages and details are explained in the following illustrations depicting a preferred
5 embodiment in which:
Fig. 1 is a view of part of the facade-casing
Fig. 2 is a facade casing according to fig. 1, including arrows indicating the flow of air
o through the individual chambers
Fig. 3 is a sectional view of the facade, including facade casing, according to intersection line
III-III in fig. 1, and
Fig. 4 is a shortened vertical section through both, facade casing and building wall, according
to intersection line IV-IV in fig. 1
Detailed Description of a Preferred Embodiment
The multi-storey building facade depicted in fig. 1 is equipped with a casing consisting of
individual cladding panels 1. The panels 1 are arranged in a distance of 20 to 40 cm from the
building wall, facilitated by mounting devices to be explained in the following. The cladding
panels 1 are arranged in a large surface horizontally between the windows 2 of one story as
25 well as vertically between the windows 2 of two subsequent stories. Each facade element 1 is
generally supported in its four corners by a mounting element attached to the building wall.
The facade panels 1 may consist of enameled, tempered glass panes, whereby these glass
panes ought to be transparent at least in front of the window openings of the building wall;
the rem:~ining panes may be fabricated from tinted glass. It is also possible to employ metal-
30 coated glass, either generally or in designated areas only.
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According to fig. 2, chamber 7 is receiving air from story I at its bottom level, whereas the
air subsequently transported through the chamber 7 is exiting at window level of story II.
The same holds true for all chambers of the facade with the exception of the upper stories.
5 According to filg. 2, chamber 7 is receiving air from story I at its bottom level, whereas the
air subsequently transported through the chamber 7 is exiting at window level of story II.
The same holds true for all chambers of the facade with the exception of the upper stories Fig.
1 illustrates thle use of different sun-breakers for facade-elements in the left line and in the
rem:~ining two lines. The left line of windows features for each window a slanted surface 3,
o located in front of the casing, whereas for the windows depicted to the right, the sun-breaker
is integrated into the building facade in form of a laminar blind 4, hence is placed in the
interior space between building wall and facade casing.
Moreover, fig. 1 shows that the facade casing is not completely closed, but features air-
15 intake-vents '; and the corresponding air-exit vents 6. In order to facilitate a natural
ventilation of the facade with fresh air, the air-intake vents 5 are positioned below the
corresponding air-exit-vents 6. Moreover, the interior space between the facade-casing and
the building wall is divided into individual chambers, whereby each one of these chambers is
featuring in its lower part an air-intake vent 5 and in its upper part two air-exit vents 6. The
20 air-intake vents 5 consist of slits, arranged almost horizontally across the width of the
window 2, whereby the air-exit vents 6 are designed as vertical slits arranged between and at
the level of the windows 2 .
The airflow passing through each individual chamber is explained in fig. 2, which
25 supplements fig. 1 through additional arrows indicating the current. At the bottom of story I
air is entering through the air-intake vent 5 into the chamber 7 located behind the facade
casing. For better clarity, the chamber 7, including both its correlated exit-canals 8, appears
double-shaded in the upper portion of fig. 1. The chamber 7 including the correlated exit-
canals 8 is U-shaped, with a distinctly enlarged base. The lower part of the chamber 7 is
30 almost rectan,~ular, of large volume and is approximately as wide as the window 2. Directly
below the nexl: air-intake vent for the chamber located above, the chamber 7 is branching out
into two exit-canals 8, which form the "legs" of the "U". In the upper part of these exit canals
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8 we find the air-exit-vents 6, through which the air is leaves the chamber 7. The lower
portion of fig. 2 demonstrates the air-flow in one single chamber 7 by way of current-arrows.
We can clearl y discern the branching of the chamber 7 below the next higher air-intake vent
5 5a of the channber 7a located above. Thus the exit-canals 8 of the chamber 7 are stretching
parallel to both sides of the chamber 7a which in each case is located above. Between
chamber 7a and the exit-canal 8 of the chamber 7 located below is a vertical separating wall
9, depicted in fig. 2 by broken lines.
o According to fig. 2, chamber 7 is receiving air from story I at its bottom level, whereas the
air subsequenfly transported through the chamber 7 is exiting at window level of story II.
The same holds true for all chambers of the facade with the exception of the upper stories
where the air flow possibly needs to be directed differently.
Fig. 1 illustrates also, that the exit-canals 8, 8a, as well as the air-exit-vents 6, 6a cannot
necessarily be assigned to one chamber 7, respectively 7a. Two adjacent chambers on the
same level sha~re one exit-canal and one air-exit vent. However, as an alternative, the interior
of exit-canals 8, 8a may include a separating wall, so that each exit-canal, including its air-
flow, would in. fact be assigned to one single chamber.
The sectional view of fig 3 illustrates an embodiment in which each exit canal 8 facilitate the
air exit of two adjacent chambers. The exit canal 8 is confined at both sides through
separating wa]ls 9, which essentially stretch from the building wall 10 to the facade casing
consisting of f acade elements 1. Each of the separating walls 9 consists of an elongated metal
box con1~ining a suitable sound-insulation material. The vents in the metal box are designed
in such a way that the sound- insulation is primarily affecting the adjacent chamber 7, the
back side of which is - at the level of the vertical section according to fig. 3 - defined through
the casement 1 1 of window 2 and the fixed window frame 12.
The space between two adjacent window frames 12, which simultaneously defines the
backside of exit canal 8, contains suitable insulation material 13 and is sealed with insulation
plaster 14. A Icnee 15 is anchored directly to the building wall 10 for connecting the window
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as well as the facade casing with the building wall 10. Attached to the knee 15 is another
knee 16, which in turn is connected to the window frame 12 and the inward pointing rim of
the separating wall 9. The outward pointing rim 17 of the separating wall 9 is connected with
5 mounting elements 18, which at the same time connect two facade panels 1 placed on top of
each other. Since details regarding the mounting elements 18, including their connection with
facade panels 1 have been described by the same applicant in European Patent EP 0 608 443
B 1, we refer to this specification for further information. However, we would like to add that
the internal part 20 of the mounting element 18 is welded to an additional carrier 21 which in
o turn is guided through the slit between two facade panels 1 and connected with a small plate
22. The slanted surface 3 serving as sun-breaker is attached to the plate 22, hence the entire
sun-breaker is supported by the mounting element 18. Consequently, each separating wall 9
has at least three functions: firstly, the separating wall 9 separates the chamber 7a from the
exit-canal 8 of the respective chamber below; secondly the separating wall 9 promotes sound
5 insulation in the adjacent chamber 7a through the embedded insulation material, and thirdly
the separating wall 9 serves as structural connection between the facade casing consisting of
facade panels 1 and the building wall 10. Moreover, the horizontal extension of the separating
wall defines the functionally important space between facade casing and building wall, which
should measure at least 15 cm, preferably between 20 and 40 cm.
Fig. 4supplements fig. 1 to 3 and illustrates how the slanted surface 3 serving as sun-breaker
can be supported through a lever system 23, enabling it to withstand stronger wind pressure
or heavy snov~. In this case, the lever system 23is installed at the subsequent lower mounting
elements 18 oi the facade casing.
According to fig. 4, the bottom 24 defining the lower boundary of chamber 7, is inclined
between the building wall 10, respectively a block 25 positioned in front of the building wall
10, and the facade casing. Key 26 denotes those openings in the separating walls 9, where the
main portion of the chamber 7 is branching into the exit canals 8.
The illustrations do not show devices for the apportioned dispensing of fluids, especially
water, onto the surface of the facade elements 1. At times of high temperatures and intensive
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sun exposure the apportioned water will evaporate, causing a cooling of the chambers, hence
a cooling of the entire building facade. Moreover, it is possible to infuse the chambers 7 with
water spray, which would have the same evaporative cooling effect.
5 Furthermore, one could of course attach photo-voltaic elements 27 to the vacant surface of the
facade panels I .
