[0001] The present invention relates to composite building elements and in particular to
composite building panels which have various applications in the building industry,
for example for building walls, floors, ceilings and roofs.
[0002] One popular method of building a wall is to build a timber frame which is then filled
with glass wool. Since these timber frames are not highly shear resistant, a plywood
sheathing is usually nailed to the timber frame. However, the plywood sheathing is
relatively expensive and it does not always provide the building element with sufficient
shear resistance. Insufficient shear resistance is also experienced when a chip board
is nailed to the timber frame instead of plywood. The use of a chip board is furthermore
disadvantageous because of the excessive weignt of the chip board which is required
to obtain satisfactory strength.
[0003] In GB patent specification 1 587 012 it is suggested to close a wall space defined
by the timber frames of a building with a foamed polyurethane or a foamed polystyrene.
However, such timber frames of which the wall space is filled with foamed polyurethane
or polystyrene sheets have several disadvantages when building the walls. First, the
size of the frame and of the foam sheet or slab must be very well adjusted to each
other in order to avoid gaps between the frame and the foam sheet or slab. Special
seals have been suggested in GB patent specification 1 587 012 in order to fill such
difficult to avoid gaps, but such seals increase the installation costs. Furthermore,
the timber frame has much lower insulation properties than the foam sheet or slab
and therefore forms thermal bridges in the building panel.
[0004] In DE-A-2 816 935 (equivalent to US-A-4 193 244) a module block is disclosed which
consists of two parallel fiber plates. To each fiber plate two parallel laths are
fixed. For connecting the two fiber plates with each other, side plates, for example
fiber plates or chip boards, are fixed to the laths perpendicularly to the first two
fiber plates. Between the four plates, an insulation material such as rock-wool is
placed. However, fiber-plates, ply-wood or chip boards of heavy weight are required
for providing sufficient shear strength to the module block. Furthermore, the side
plates produced of fiber plates, chip board or ply-wood boards have insufficient insulation
properties and therefore form thermal bridges in the module block.
[0005] Therefore, it is desirable to provide a composite building element which does not
only have good insulation properties but also high strength, in particular high shear
resistance. It is also desirable to provide a building element which can be prefabricated
and easily installed and which preferably has a relatively low weight.
[0006] The present invention provides a composite building element which comprises
a) a core panel of a rigid foamed material of an expanded synthetic resin and
b) two stiff frames of essentially the same length and the same width as the length
and width of the core panel which frames are bonded to the back and front surface
of the core panel.
[0007] The composite building element of the present invention has a surprisingly high resistance
to shearing forces.
[0008] Furthermore, the composite building element of the present invention does not provide
thermal bridges.
Fig. 1 illustrates a back perspective view on a first embodiment on the composite
building element of the present invention.
Fig. 2 illustrates a front perspective view on the first embodiment on the composite
building element.
Fig. 3 represents a schematic illustration of the cross-section of the composite building
element along line A - A in Figs. 1 and 2.
Fig. 4 to 7 are schematic illustrations of the cross-section of further embodiments
of the composite building element of the invention.
[0009] The composite building element of the present invention will be further described
with reference to the drawings.
[0010] With reference to Fig. 1, the composite building element comprises a core panel 1
of a rigid foamed material of an expanded synthetic resin, such rigid foamed polyurethane
or rigid foamed polystyrene. Preferably, the core panel 1 is a rigid extruded polystyrene
panel which has a density of from 20 kg/m , preferably of from 30 kg/m
3, to 60 kg/m
3, preferably to 50 kg/m
3. Most preferably, the core panel is moisture resistant. The thickness of the core
panel 1 depends on the desired insulating properties and strength of the building
element. Preferably, the thickness is from 30 mm to 200 mm, most preferably from 50
mm to 120 mm. The length and width of the panel is not critical. Usual lengths are
from 2 to 6 m, preferably from 2 to 3 m. Usual widths are from 0.6 to 12 m, preferably
from 1 to 5.
[0011] A stiff back frame 3 and a stiff front frame 5 are fixed to the back surface 2 and
front surface of the core panel 1. The frames 3, 5 have essentially the same length
and same width as the length and width of the core panel 1, however, it is not necessary
that the length and width of the frames 3, 5 are exactly the same as those of the
core panel 1. The back frame 3 consists of a first set of at least two parallel laths
7a, 7b and a second set of at least two parallel laths 7c, 7d which are perpendicular
to the laths 7a, 7b. As illustrated by Fig. 1, the back frame 3 can be subdivided
by one or more additional laths 8 which are preferably parallel to the main laths
7c, 7d.
[0012] The laths 7a, 7b, 7c, 7d and 8 can be produced of any sufficiently strong and stiff
material to resist forces which are applied perpendicularly to the smallest cross-section
of the back frame 3, i.e. to the cross-section along line A - A and perpendicularly
to the plane defined by the back frame 3. Usual materials are for example wood, metal,
concrete or hard plastic materials. If the back frame 3 is produced of wood, the main
laths 7a, 7b, 7c, 7d have preferably a cross-section of from 20 x 20 mm to 150 x 150
mm, most preferably of from 50 x 50 mm to 100 x 100 mm. The additional lath 8 can
have the same cross-section. In general, the cross-section of the additional lath
8 is smaller, for example from 20 x 20 mm to 80 x 80 mm, preferably from 25 x 25 mm
to 50 x 50 mm. Fig. 1 illustrates that the back frame 3 and the front frame 5 are
not in contact with each other. Therefore, the composite building element of the present
invention does not provide the undesired thermal bridges through the thickness of
the building element. The back frame 3 and front frame 5 can be fixed to the core
panel 1 in any suitable means, preferably by applying an adhesive such as a polyurethane
adhesive between the adjacent surfaces of the back frame 3 and the core panel 1 and
between the adjacent surfaces of the front frame 5 and the core panel 1.
[0013] The main back laths 7a, 7b, 7c, 7d and optionally the additional back lath 8 can
be fixed to each other by any suitable means to build the back frame 3 such as nailing
or gluing.
[0014] If desired, the corners of the back frame 3 can be reinforced, for example by metal
plates which are fixed to the corners of the back frame 3 and to the core panel 1.
[0015] Fig. 2 illustrates the same embodiment of the composite building element of the present
invention as Fig. 1, however, Fig. 2 represents a perspective front view on the building
element. Fig. 2 illustrates a core panel 1 as described with reference to Fig. 1.
A stiff front frame 5 is fixed to the front surface 12 of the core panel 1. The front
frame 5 is built of a first set of at least two parallel laths 9a, 9b and a second
set of at least two parallel laths 9c, 9d which are perpendicular to the first set
of laths 9a, 9b. The frame consisting of the main laths 9a, 9b, 9c, 9d can be subdivided
by one or more optional additional front laths 10. The front laths 9a, 9b, 9c, 9d
and 10 can have the same dimension as the back laths 7a, 7b, 7c, 7d and 8 described
with reference to Fig. 1. Cut out along the edges of the front surface 12 of the core
panel 1 are rabbets (see 14a and 14b in Fig. 3) which have essentially the same widths
and depths as the widths and thickness of the main front laths 9a, 9b, 9c, 9d. The
front surface 12 of the core panel 1 is further provided with a groove (see 16 in
Fig. 3) extending parallel to the edges of the core panel 1 and which has essentially
the same dimensions as the cross-section of the additional front lath 10. The front
laths 9a, 9b, 9c, 9d and 10 are placed in these rabbets and this groove and fixed
to the core panel 1.
[0016] As an alternative or in addition to the rabbets and groove(s) in the front surface
12 of the core panel 1, the back surface 2 of the core-panel 1 can be provided with
rabbets and/or one or more grooves.
[0017] Fig. 1 and 2 illustrate composite building elements of rectangular shape. In some
cases however, it may be desirable that the core panel does not have a rectangular
back or front surface but that is has surfaces of a triangular or trapezoid shape.
Such shapes are for example preferred when building the portion of a wall which will
be in contact with a sloped roof. In such a case, the two stiff frames are adjusted
to the shape of the core panel. In one embodiment of the frames, each frame consists
of one set of at least two parallel laths, a lath which is perpendicular to this set
of parallel laths and one lath which is neither parallel nor perpendicular to this
set of parallel laths.
[0018] Fig. 3 illustrates a cross-section along the line A - A in Figs. 1 and 2. Fig. 3
illustrates how the main back laths 7c, 7d and the additional back lath 8 are arranged
on the back surface 2 of the core panel 1. The front surface 12 of the core panel
1 is provided with rabbets 14a, 14b and with a groove 16. The main front laths 9c,
9d and the additional front lath 10 are placed in these rabbets 14a, 14b and the groove
16 respectively and fixed to the core panel 1.
[0019] Fig. 4 illustrates how the composite building panel described with reference to Fig.
3 can be combined with other materials to build a complete wall. An interior finishing
layer 20, for example a wood sheet or a gypsum plaster board is attached to the main
back laths 7c, 7d and to the additional lath 8 as well as to the main back laths 7a,
7b (not shown). Thereby a space 22 is built which allows any pipes and electric cables
to be fit into the building element in a convenient way. The front surface 12 of the
core panel 1 is covered with an external rendering 24.
[0020] Fig. 5 illustrates a cross-section through another embodiment of the composite building
element of the present invention. The main front laths 9e, 9f, the main front laths
9a, 9b (not shown) and the additional front lath 11 are not flush with the front surface
12 of the core panel 1 but are protruding. An external finishing material 26 such
as a wood cladding can be attached to the main front laths 9e, 9f, to the main front
laths 9a, 9b (not shown) and to the additional front lath 11 whereby a second space
28 in addition to space 22 is provided.
[0021] In Fig. 6 a type of cross-section of the main back laths 7e, 7f and of the additional
back lath 18 is illustrated which allows the attachment of a fire protection material
30, such as a gypsum layer, directly to the back surface 2 of the core panel 1.
[0022] Fig. 7 illustrates a cross-section through an embodiment of the composite building
element similar to that illustrated by Fig. 5. However, the front surface 12 of the
core panel 1 is not provided with grooves or rabbets.
[0023] The following example illustrates the composite building element of the present invention
and its shear resistance compared to known building elements used in the industry.
Example
[0024] A type of composite building element illustrated in Figs. 1 to 3 is tested. The core
panel consists of rigid extruded polystyrene foam of a density of about 45 kg/m
3. The length of the panel is 240 cm, the width 120 cm and the thickness 80 mm. The
stiff back frame is built of four main spruce laths of 75 mm x 55 mm cross-section
and an additional spruce lath of 40 mm x 55 mm cross-section. In the corners, the
main timber frame built by the spruce laths of 75 mm x 55 mm cross-section is reinforced
by diagonally divided square steel nail plates of 300 mm side length and a thickness
of 2 mm. The steel plates are nailed irregularly and glued with a polyurethane adhesive
to the back frame and to the core panel. The stiff front frame is built of four main
spruce laths and an additional spruce lath of 50 mm x 30 mm cross-section. The back
and front timber frames are glued with a polyurethane adhesive to the back and front
surfaces of the core panel.
Comparative Example A
[0025] A spruce frame of 240 cm length and the same width is produced of
- 5 parallel laths of 240 cm length placed at equal distance from each other, the
middle lath has a cross-section of 45 x 97 mm and the other four laths have a cross-section
of 36 x 97 mm, and
- a pair of studs of 36 x 97 mm cross-section which are perpendicular to the set of
5 parallel laths. Each stud is fixed to each lath with two nails of 3.3 x 90 mm.
[0026] The shear resistance of this frame is provided by a sheet of 8 mm plywood nailed
with nails (2.1 x 45 mm) on each lath and stud of the frame, every 15 cm on the studs
and the two outside laths and every 30 cm on the three middle laths. A gypsum plaster
board is nailed to the other side of the frame. The space between these two faces
is filled with a glass fiber insulation of 100 mm thickness.
Comparative Example B
[0027] The same frame as described in comparative Example A is produced. The shear resistance
is provided on both sides by a sheet of 12 mm chipboard nailed with nails (2.8 x 55
mm) every 15 cm on the studs and the two outside laths and every 30 cm on the three
middle laths of the frame. The space between the two chipboard sheets is filled with
a glass fiber insulation of 100 mm thickness.
[0028] For testing the shear resistance of the building elements, two identical composite
building panels of the Example are installed vertically side by side, fixed firmly
to the floor and interconnected. One panel of each of comparative Examples A and B
is also installed vertically and fixed firmly to the floor. Across the surface of
the panels variable horizontal shearing forces are applied near the upper edge of
the panels. The following table illustrates the weight of the building elements, the
horizontal shearing force (load) which needs to be applied until the building element
breaks, the horizontal shearing force (load) which is necessary to cause 5 mm deflection
of the building element in the cases where a) no vertical load and b) additionally
2.5 kN vertical load is applied and the insulation properties of the building elements.
1. A composite building element comprising
a) a core panel (1) of a rigid foamed material of an expanded synthetic resin and
b) two stiff frames (3, 5) of essentially the same length and the same width as the
length and width of the core panel (1), bonded to the back and front surfaces (2,
12) of the core panel (1).
2. The composite building element of claim 1 wherein each frame (3, 5) consists of
a first set of at least two laths (7a, 7b, 9a, 9b) and a second set of laths (7c,
7d, 7e, 7f, 8, 9c, 9d, 9e, 9f, 10, 11) whereby the laths of the second set are parallel
to each other and are perpendicular to at least one lath of the first set.
3. The composite building element of claim 1 wherein each frame (3, 5) consists of
a first set of at least two parallel laths (7a, 7b, 9a, 9b) and a second set of at
least two parallel laths (7c, 7d, 7e, 7f, 8, 9c, 9d, 9e, 9f, 10, 11) which second
set of laths is perpendicular to the first set of laths and the laths have a cross-section
of from 20 mm x 20 mm to 150 mm x 150 mm.
4. The composite building element of claim 2 or 3 wherein the laths of the frames
are made of wood, metal or concrete.
5. The composite building element of any of claims 1 to 4 wherein the core panel (1)
is a rigid extruded polystyrene foam panel having a density of from 20 to 60 kg/m3.
6. The composite building element of claim 5 wherein the core panel (1) is a rigid
extruded polystyrene foam panel having a density of from 30 to 50 kg/m3.
7. The composite building element of any of claims 1 to 6 wherein the front and/or
the back surface (12, 2) of the core panel (1) is provided with a rabbet (14a, 14b)
along the edges of the core panel (1) and/or with one or more grooves (16).
1. Verbundbauelement enthaltend
a) eine Kernplatte (1) aus hartem aufgeschäumten Material eines expandierten synthetischen
Harzes und
b) zwei steife Rahmen (3, 5) von im wesentlichen der gleichen Länge und Breite wie
die Länge und Breite der Kernplatte (1), die mit der hinteren und vorderen Oberfläche
(2, 12) der Kernplatte (1) verbunden sind.
2. Verbundbauelement nach Anspruch 1, dadurch gekennzeichnet, daß jeder Rahmen (3,
5) aus einem ersten Satz aus mindestens zwei Latten (7a, 7b, 9a, 9b) und einem zweiten
Satz von Latten (7c, 7d, 7e, 7f, 8, 9c, 9d, 9e, 9f, 10, 11) besteht, wobei die Latten
des zweiten Satzes jeweils parallel zueinander und senkrecht zu mindestens einer Latte
des ersten Satzes angeordnet sind.
3. Verbundbauelement nach Anspruch 1, dadurch gekennzeichnet, daß jeder Rahmen (3,
5) aus einem ersten Satz von mindestens zwei parallelen Latten (7a, 7b, 9a, 9b) und
einem zweiten Satz von mindestens zwei parallelen Latten (7c, 7d, 7e, 7f, 8, 9c, 9d,
9e, 9f, 10, 11) besteht, wobei der zweite Satz von Latten senkrecht zum ersten Satz
von Latten angeordnet ist, und die Latten einen Querschnitt von 20 mm x 20 mm bis
150 mm x 150 mm aufweisen.
4. Verbundbauelement nach Anspruch 2 oder 3, dadurch gekennzeichnet, daß die Latten
der Rahmen aus Holz, Metall oder Zement sind.
5. Verbundbauelement nach jedem der Ansprüche 1 - 4, dadurch gekennzeichnet, daß die
Kernplatte (1) eine extrudierte Polystyrolhartschaumplatte mit einer Dichte von 20
- 60 kg/m3 ist.
6. Verbundbauelement nach Anspruch 5, dadurch gekennzeichnet, daß die Kemplatte (1)
eine extrudierte Polystyrolhartschaumplatte mit einer Dichte von 30 - 50 kg/m3 ist.
7. Verbundbauelement nach jedem der Ansprüche 1 - 6, dadurch gekennzeichnet, daß die
Vorder- und/oder Rückseite (12, 2) der Kernplatte (1) mit einem Falz (14a, 14b) entlang
der Kanten der Kernplatte (1) und/oder mit einer oder mehreren Nuten (16) versehen
sind.
1. Panneau de construction composite comprenant:
a) un panneau (1) formant l'âme réalisé en une mousse rigide de résine synthétique
expansée, et
b) deux cadres rigides (3, 5) sensiblement de la même longueur et de la même largeur
que la longueur et la largeur du panneau (1) formant l'âme, qui sont collés sur les
surfaces avant et arrière (2, 12) du panneau (1) formant l'âme.
2. L'élément de construction composite de la revendication 1, dans lequel chaque cadre
(3, 5) consiste en une première série d'au moins deux lattes (7a, 7b, 9a, 9b) et une
seconde série de lattes (7c, 7d, 7e, 7f, 8, 9c, 9d, 9e, 9f, 10, 11), les lattes de
la seconde série étant parallèles entre elles et perpendiculaires à au moins une des
lattes de la première série.
3. L'élément de construction composite de la revendication 1, dans lequel chaque cadre
(3, 5) consiste en une première série d'au moins deux lattes parallèles (7a, 7b, 9a,
9b) et une seconde série d'au moins deux lattes parallèles (7c, 7d, 7e, 7f, 8, 9c,
9d, 9e, 9f, 10, 11) laquelle seconde série de lattes et les lattes ayant une section
transversale allantde20mmx20mmà150mmx150mm.
4. L'élément de construction composite de la revendication 2 ou 3, dans lequel les
lattes des cadres sont réalisées en bois, en métal ou en béton.
5. L'élément de construction composite de l'une quelconque des revendications 1 à
4, dans lequel le panneau (1) formant l'âme est un panneau de mousse de polystyrène
extrudé rigide dont la densité est de 20 à 60 kg/m .
6. L'élément de construction composite de la revendication 5, dans lequel le panneau
(1) formant l'âme est un panneau de mousse de polyestyrène extrudé rigide dont la
densité est de 30 à 50 kg/m3.
7. L'élément de construction composite de l'une quelconque des revendications 1 à
6, dans lequel la surface avant et/ou la surface arrière (12, 2) du panneau (1) formant
l'âme est munie d'une rainure (14a, 14b) sur les bords du panneau (1) formant l'âme
et/ou comportant une ou plusieurs gorges (16).