WO2003091508A1

WO2003091508A1 - Composire board for underroof and mounting methods for the same

Info

Publication number: WO2003091508A1
Application number: PCT/DK2003/000227
Authority: WO
Inventors: Jens Borry Henriksen
Original assignee: Henriksen Holding Aps
Priority date: 2002-04-23
Filing date: 2003-04-08
Publication date: 2003-11-06
Also published as: AU2003226922A1

Abstract

The present invention relates to a building element (1), primarily for an underroof or a wall construction comprising at least two layers of materials, where said building element has a surface layer (2) and a panel layer (3), and where at least one of said layers comprises a cellulose compound wherein the said surface layer (2) is a diffusion-open or diffusion tight layer, and said panel layer (4) is formed with a rebate (4) along all side edges of said building element (1). The present invention furthermore relates to methods for mounting said building element (1) as an underroof construction (20) or a wall construction (30).

Description

Composite board for underroof and mounting methods for the same

FIELD OF THE INVENTION

The present invention relates to a building element, primarily for an underroof or a wall construction comprising at least two layers of materials, where said building element has a surface layer and a panel layer, and where at least one of said layers comprises a cellulose compound.

The present invention furthermore relates to methods for mounting said building element as an underroof or a wall construction.

BACKGROUND OF THE INVENTION

Roof constructions with underroofs are built either as: - an underroof made of wood boards or plywood-covered, i.e. bitumen cardboard or other hydrophobic layers, or

- an underroof made of overlapping plates, or

- an underroof made of plates with overlapping rebates, or

- an underroof made of web material.

Each type of underroof construction has advantages and disadvantages.

Noticeable advantages of an underroof made of plates or boards are that it is suitable for withstanding wind and physical loads, and constitutes a firm underlying layer, which protects against penetration.

Noticeable advantages of an underroof made of web material are that it is suitable for absorbing condensed water and/or repel drift snow, rain, dust and the like. The disadvantages of both types of underroofs are that is not possible to transfer the aforementioned advantages of an underroof made of boards to an underroof made of a web material, and vice versa.

Furthermore all the aforementioned types of underroof constructions lack any kind of insulation layer around the edges of the building elements (or webs) to prevent the formation of thermal bridges.

OBJECT OF THE INVENTION

One object of the invention is to produce a building element which is easy to mount as an underroof and/or a wall construction and where said building element combines the aforementioned advantages of an underroof and/or a wall construction made of either plate material or web material in such a manner that the building element is an insulating element being weather-proof against water and wind, and so that when said building element is placed and assembled in a construction, a wind-tight and waterproof barrier is created.

This is obtained with a building element as described in the preamble of claim 1 and characterised in that said surface layer is a diffusion-open layer, and said panel layer is formed with a rebate along all side edges of said building element.

Another object of the invention is to provide methods for mounting said building element as an underroof or a wall construction.

This is obtained by the methods described below, where a method for mounting said building element as an underroof construction comprises the following steps:

- the rafters (21 ) and tie beams of the building are raised, - the base of the roof (51 ) and the fascia boards are mounted, - said building element (1) is mounted from the base of the roof (51) and upwards in a horizontal and floating course of butt joints (52), whereby said rebates (4) of said panel layers (3) of adjacent building elements (1) are overlapping,

- said building element (1) is gradually covered with laths (23) and spacers (22) as said building elements (1) are being mounted,

- fitting work on said underroof in connection with the barge board, hip, perforations, and valleys of the roof is carried out.

And where a method for mounting said building element as a wall construction (30), comprises the following steps:

- the wall studs (31), braces, window sills and/or door openings of the building are erected,

- said building element (1) is mounted on the outside and/or the inside of said wall studs (31) from the sill and upwards, in a horizontal and floating butt joint (52) course, whereby said rebates (4) of said panel layers (3) of adjacent building elements (1) are overlapping,

- work of said wall construction (30) is finished.

DESCRIPTION / SUMMARY OF THE INVENTION

To manufacture a building element that combines the advantages of a solid construction and a web construction the building element according to the present invention is a composite building element comprising two or more layers of material.

The building element has a surface layer which in one embodiment of the invention is made as a diffusion-open layer. This causes the surface layer to be a one-way airtight layer which can protect the underlying layers of the building element against unwanted encroachment of water and wind.

Within the scope of this invention the terms "airtight" and "airproof and "watertight" and "waterproof shall be given the following meaning: Airtight is used to describe a barrier where one air pressure can be maintained on one side of the barrier and another air pressure on the opposite side. A certain diffusion is or may be allowed through the barrier, i.e. it is diffusion open.

Similarly, by watertight shall be understood a barrier which will be able to withstand a certain difference in water pressure on opposite sides of the barrier. A certain minimal transport of water through the barrier may be allowed.

To form a building element core having an insulating characteristic, the panel layer, which is connected to the surface layer, comprises a cellulose compound, which has a low heat transfer coefficient λ, preferably app. 10 W/mK.

It is easy to handle a building element because the layers are connected together. The connection between the surface layer and the panel layer is achieved for example by adhesive means, for example a hot-melt process, to assemble the two layers.

The building elements are formed in such way that the assembling of a number of building elements to form a panel, for example an underroof, is very easy because from the shape of the panel layer edges it is evident how the elements should be mounted. Thus it is not possible to assemble two adjacent building elements incorrectly.

To form such a safe-assembly junction, the panel layer is formed with a rebate along all side edges of said building element whereby two adjacent building elements are assembled in such a manner that a rebate on one side edge of a first building element corresponds to a reversed rebate on a side edge of a second adjacent building element.

Furthermore the rebate junctions will cause a building element to be fixed in a locked position when it is mounted adjacent to another building element.

The building elements are mounted on and fastened to the underlying rafter structure of the roof of the building. To increase the fixation of the underroof and the concurrent proofing of the underroof, the rebate junction may in an alternative embodiment of the invention be fixed or adhered together with for example nails, clamps or glue.

As an alternative the building elements according to the invention may be fastened by means of the lath structure or the distance keepers used for mounting the roofing or wall material.

To increase stability and/or to ensure the air/water proofing of one or both sides of a building element, the said building element may comprise a number of further layers. In another embodiment of the present invention said building element furthermore comprises a backside layer placed on the opposite side of said surface layer on said panel layer.

Such a building element is a composite construction with an insulating and solid panel layer between an air-/water-proof surface layer and a strengthening backside layer.

To produce an underroof or wall construction it is necessary to assemble a number of building elements to form the wanted construction. To save time and make the assembly of the construction easy, it is an advantage if the building elements have the same circumferential characteristics whereby it is not necessary to turn or turn over a building element to fit it together with an adjacent building element.

Furthermore, during production, packaging and transport it is advantageous to have elements having only one circumferential set of characteristics of the building elements.

In an embodiment of the present invention, said building element is primarily a quadrangular building element, for example a trapeze, a parallelogram, a quadrant or a rectangle. The most common type would be rectangular building elements with one long side and a smaller side, whereby it is possible to mount one building element to more than one underlying rafter on a roof structure.

Also for the builders handling the building element it is possible to handle large elements due to the relatively low weight and the interior strength of the element. When the elements are rectangular, the workers can grip the elements on the short side when handling the elements.

Alternatively the building elements could have the same form as the pieces in a jigsaw puzzle. This would strengthen the mutual fixation of the building elements.

In another embodiment of the invention the rebate on said panel layer is formed on one side and with one encircling rebate along all the side edges of said panel layer. To assemble such building elements it is necessary to turn over every other building element in the sequential mounting of building elements.

In another embodiment of the invention said panel layer is formed with one said rebate along two coherent side edges on one side of said panel layer, and with another said rebate along the two other coherent side edges on the opposite side of said panel layer.

The assembling of such building elements would be very easy, especially if the building elements are mounted in such way that the rebate is visible on these two coherent side edges where an adjacent building element subsequently is mounted with one of the two coherent side edges where the rebate is on the down-facing side. It is then possible to mount a whole underroof or wall construction from a base point and upwards.

The building elements are mounted in a horizontal and floating butt joint course, and each row of building elements is shifted slightly sideways so that butt joints of rows of the subjacent building elements are not aligned, which could cause structural weakness of the underroof as well as leaks for water and air to penetrate. The horizontal shifting of building elements cause the floating butt joint to be placed randomly in relation to the under lying rafter, which means that there is no solid structure under a number of butt joints. To maintain the fixation of the building elements the overlapping rebate butt joint are used. But without any firm internally fixation of the rebates of the butt joint, the underroof may over time or in bad weather conditions be working itself loose so that a leakage can emerge between the building elements.

To prevent any leakage between building elements and to ensure that the underroof or wall construction is totally water- and/or air-proof, said surface layer is provided with an overlapping edge part at least along two coherent side edges of said building element.

In an embodiment of the invention, the overlapping edge parts of the surface layer are provided along the coherent side edges of a quadrangular building element where the rebate faces downwards. This allows the overlapping part to be spread out and cover the junction between the juxtaposed and subjacent building elements.

The overlapping edge parts of the surface layer have to be fixed to the surface layer of a juxtaposed and/or subjacent building element. In another embodiment of the invention, the fixation of the overlapping surface layer is done by placing laths and spacers for the roof of the building.

To ensure that it is almost impossible for water and air to force their way into the building through the underroof structure, said overlapping edge part is provided with an adhesive or glued in situ. Preferably covered adhesive tape may be provided.

To fix the overlapping edge part to the surface layer of a juxtaposed and/or subjacent building element, the cover of the adhesive tape is removed, and the overlapping edge parts are pressed down and fixed to the surface layer of a juxtaposed and/or subjacent building element. Alternatively the overlapping edge part can be fixed to the surface layer of a juxtaposed and/or subjacent building element with glue, which is hot-melted to attach the overlapping edge part to the surface layer.

The surface layer is formed from an air-/water-resistant and diffusion-open material such as polyethylene plastic or the like.

The panel layer is formed from a cellulose compound such as compressed wood wool, wood cement, wood concrete, or the like.

By using wood cement is it possible to produce a building element with some of the characteristics of a porous insulating element, and which is in a solid form whereby it can endure high loads of wind, snow, or other physically loads.

The backside layer is formed from a woven or non-woven material, which is manufactured in such way that the backside layer supports and provides strengths to the panel and surface layer, whereby it is possible to produce larger or stronger building elements.

In an alternative embodiment of the invention the surface layer and the backside layer are formed of the same material and, for example, with overlapping edge parts on opposite sides of the building element and on opposite coherent side edges. This ensures that it is virtually impossible to mount the building element incorrectly.

The method for mounting said building elements as an underroof construction comprises the following steps:

- the rafters and tie beams of the building are raised,

- the base of the roof and the fascia boards are mounted, - said building element is mounted from the base of the roof and upwards in a horizontal and floating course of butt joints whereby said rebates of said panel layers of adjacent building elements are overlapping, - said building element is gradually covered with laths and spacers as said building elements are being mounted,

- fitting work on said underroof in connection with the roofs barge board, hip, perforations, and valleys is carried out.

When the underroof is mounted from the base of the roof and upwards in a horizontal and floating butt joint course, the overlapping edge parts of the surface layer unfold from a higher placed building element downwards which is the most suitable way to spread out the overlapping edge parts. The reason is that in this way, no projections are formed at which downwards running water or snow can gather on the underroof.

The method for mounting said building elements as a wall construction comprises the following steps:

- the wall studs, braces, window sills and/or door openings of the building are erected,

- said building element is mounted on the outside and/or the inside of said wall studs from the sill and upwards, in a horizontal and floating butt joint course, whereby said rebates of said panel layers of adjacent building elements are overlapping,

- work on said wall construction is finished.

The building element can be used for both an inner wall and an outer wall.

If used for a double wall, the space between the two sidewalls of the building element can be filled with sound-insulating materials, and/or further heat insulation materials, electric wave-reflecting material, and/or fire-resistant material.

The finishing work on the wall construction comprises for example:

- filling up the cracks to smooth the surface of the building elements,

- mounting a woven fibre web, wall paper, or the like, - painting the surface. The underroof and/or wall construction are made air-/water-proof either by arranging one part of said overlapping edge part of said surface layer over a juxtaposed building element, and arranging another part of said overlapping edge part of said surface layer over a subjacent building element, or by removing the cover of said adhesive tape on said overlapping edge part, thereby fastening the surface layer of one building element to a juxtaposed and/or a subjacent building element.

The building elements are mounted on-site and are fastened with screws, nails or the like to the rafters or studs. Adjustments of the length of a building element at the ends of the underroof/wall can be done just by sawing though the solid panel layer of the building elements and cutting through the surface layer and/or backside layer.

The builders who mount the building element as either an underroof or a wall will always begin from the bottom of the construction and work their way upwards. Thus the aforementioned method for making the construction air-/water-proof is preferable because it enables the securing of a satisfactory air/water proofing of the first two mounted rows of building elements before mounting another row of building elements.

The different embodiments of the invention may be used in situ, i.e. the elements may be applied at the construction site. The elements according to the invention are also suitable for pre-manufacture of building elements, which after manufacture are transported to the building site and included in the construction as pre-made roof constructions or elements thereof, alternatively wall elements or entire wall sections.

The building element according to the present invention can be used for building underroof constructions and wall constructions in any kind of building.

Furthermore the building element can be used for specific situations, for example: - where it is necessary to have a closed internal environment with controlled ventilation, or - where it is necessary to have a water-proof screening of utility rooms, toilets, and baths rooms from the other areas of the building.

SHORT DESCRIPTION OF THE DRAWINGS

The invention is explained in more detail below with reference to the drawing in which

Fig. 1 shows a side view of a building element according to the invention, Fig. 2 shows a plan view of the building element in Fig. 1 ,

Fig. 3 shows a side view of a building element according to the invention,

Fig. 4 shows a plan view of the building element in Fig. 3,

Fig. 5 shows a sectional view of a roof construction,

Fig. 6 shows a sectional view of a outer wall construction, Fig. 7 shows a sectional view of a inner wall construction,

Fig. 8 shows an underroof construction assembled of a number of building elements according to the invention,

Fig. 9 shows sectional view of a passage between a roof and a wall.

DETAILED DESCRIPTION / PREFERRED EMBODIMENT

Fig. 1 shows a building element 1 comprising a surface layer 2 and a panel layer 3, which is formed with rebates 4a, 4b.

The panel layer 3 is formed with rebate 4a facing downwards at one side edge 6 and rebate 4b facing upwards at another side edge 7 of the building element 1.

The surface layer 2 has an overlapping edge part 5 along the side edge 6, where the rebate 4a is facing downwards. Fig. 2 shows the building element 1, where the surface layer 2 covers the panel layer 3. Along the two coherent side edges 7, 8 rebate 4b, 4c is shown, which is not covered by the surface layer 2.

The surface layer 2 has an overlapping edge part 5 along the two coherent side edges

6, 9 where the rebate (not shown) is facing downwards.

The surface layer 2 makes this building element 1 air- and water-proof and can be used in wall constructions.

Fig. 3 shows a building element 10 comprising a surface layer 2, a panel layer 3, and a backside layer 11.

The panel layer 3 is formed with rebate 4a facing downwards at one side edge 6 and rebate 4b facing upwards at another side edge 7 of the building element 10.

The surface layer 2 has an overlapping edge part 5 along the side edge 6, where the rebate 4a is facing downwards.

The backside layer 11 has the same shape as the down-facing side of panel layers 3.

Fig. 4 shows the building element 10, where the surface layer 2 covers the panel layer 3. Along the two coherent side edges 7, 8 rebate 4b, 4c is shown, which is not covered by the surface layer 2.

The surface layer 2 has an overlapping edge part 5 along the two coherent side edges 6, 9 where the rebate (not shown) is facing downwards.

The surface layer 2 makes this building element 10 air- and water-proof and the backside layer 11 provides strength to the building element 10, which can be used in underroof constructions. Fig. 5 shows a roof construction 20 comprising a rafter 21, two building elements 10, a spacer 22, and a lath 23.

Building elements 10 are mounted on both sides of the rafter 21. The space between the building elements 10 on the upwards facing side of the rafter 21 and the building elements 10 on the downwards facing side of the rafter 21 are filled with an insulation material 25.

On the downwards facing side 26 of the building elements 10 on the downwards facing side of the rafter 21, an interior covering 24 is mounted.

On the upwards facing side 27 of the building elements 10 on the upwards facing side of the rafter 21, a spacer 22 is mounted right above the underlying rafter 21. On the spacer 22 a lath 23 is mounted, whereupon the roof is laid.

The spacer 22 ensures that there is a space between the roof and the underroof.

Fig. 6 shows an outer wall construction 30 comprising a stud 31 and two building elements 1.

Building elements 1 are mounted on both sides of the stud 31. The space between the building elements 1 on the outer side of the stud 31 and the building elements 1 on the inner side of the stud 31 is filled with an insulation material 32.

On the inner side 33 of the building elements 10 on the inner side of the stud 31 an interior covering 34 is mounted.

At the outer side 35 of the building elements 1 on the outer side of the stud 31 a climate screen 36 is mounted, which is placed with a small air space 37 apart from the outer side 35. Fig. 7 shows an inner wall construction 40 comprising a stud 41 and two building elements 1.

Building elements 1 are mounted on both sides of the stud 41. The space between the building elements 1 is filled with an insulation material 42.

At side 43 of the building elements 1 an interior covering 44 is mounted.

At side 45 of the building elements 1 a climate screen 46 is mounted, which is placed with a small air space 47 apart from the side 45.

Fig. 8 shows an underroof construction 50 comprising a roof base 51, a number of rafters 21, and a number of building elements 10.

The building elements 10 are mounted from the base of the roof 51 and upwards, in a horizontal and floating course of butt joints 52, whereby the rebate 4 of adjacent building elements 10 are overlapping.

The building elements 10 are mounted in rows, where each row is shifted horizontally to avoid that the butt joints 52 are aligned.

The floating butt joints 52 are placed randomly on the underroof construction and not upon an under-lying rafter 21.

The building elements 10 are mounted on the rafter 21 with screws, nails, clamps or the like. Alternatively, the elements may be mounted by fastening of the distance keepers or spacers 22 or the laths 23.

Fig. 9 shows the passage between a roof construction 60 and a wall construction 61. The roof construction 60 comprises a roof 63 and an underroof construction 64, which is formed as a composite construction with an upper layer of building elements 10 and a lower layer of building elements 1 and insulation 62 between these layers.

The building elements 1, 10 are mounted so that the rebates 4 of adjacent building elements 1, 10 are engaging. The overlapping edge parts 5 of the surface layer 2 are adhered to the subjacent building element 1, 10 to form an air- and water-proof surface.

The wall construction 61 is formed as a composite construction with two layers of building elements 1 and insulation 62 between these layers.

The building elements 1 are mounted so that the rebates 4 of adjacent building elements 1 are engaging. The overlapping edge parts 5 of the surface layer 2 are adhered to the subjacent building element 1 to form an air- and water-proof surface.

In the interior passage 65 between the underroof construction 64 and the wall construction 61, the overlapping edge part 5 of the surface layer 2 of the first building element 1 of the roof is bent around and adhered to the surface layer 2 of the upper building element 1 of the wall construction 61.

EXAMPLE

A building element is a rectangular and composite building element with the size of 300 x 2400 millimetres.

The building element comprises a surface layer, a panel layer with rebates along the side edges and a backside layer.

Along one long side edge and along a coherent short side edge an upwards-facing rebate is formed. Along the opposite long side edge and the coherent short side edge the rebate is facing downwards. The rebate is approximately 20 mm deep. The surface layer has an overlapping edge part along these side edges where the rebate is facing downwards. The overlapping edge part has a width of approximately 70 mm.

The backside layer has the same shape as the panel layer.

The surface layer and backside layer are glued to the panel layer preferably using the hot-melt method.

The cover paper for the adhesive tape is a silicone paper, which easily can be removed before fastening of the overlapping edge part to an adjacent building element.

Claims

1. A building element (1), primarily for an underroof or a wall construction comprising at least two layer of materials, said building element having a surface layer (2) and a panel layer (3), and at least one of said layers comprising a cellulose compound, characterised in that said surface layer (2) is a diffusion-open layer, and said panel layer (4) is formed with a rebate (4) along all side edges of said building element (1).

2. A building element (1) according to claim 1, characterised in that said building element furthermore comprises a backside layer (11), which is placed on the opposite side of said surface layer (2) on said panel layer (3).

3. A building element (1) according to any of the claims 1 or 2, characterised in that said building element (1 ) primarily is a quadrangular building element (1 ).

4. A building element (1) according to any of the claims 1 to 3, characterised in that said panel layer (3) is formed with one said rebate (4) along two coherent side edges on one side of said panel layer (3), and with another said rebate (4) along the two other coherent side edges on the opposite side of said panel layer (3).

5. A building element (1) according to any of the claims 1 to 4, characterised in that said surface layer (2) is provided with an overlapping edge part (5) at least along two coherent side edges of said building element (1).

6. A building element (1) according to claim 5, characterised in that said overlapping edge part (5) is suitable for glueing or alternatively provided with a covered adhesive tape.

7. A building element (1) according to any of the claims 1 to 6, characterised in that - said surface layer (2) is formed from an air-/water-resistant and diffusion-open material such as polyethylene plastic or the like,

- said panel layer (3) is formed from a cellulose compound such as compressed wood wool, wood cement, wood concrete, or the like, — said backside layer (11) is formed from a woven or non-woven material.

8. A method for mounting said building element (1) according to any of the claims 1 to 7, as an underroof construction (20), c h a r a c t e r i s e d in that:

- the rafters (21) and tie beams of the building are raised, - the base of the roof (51) and the fascia boards are mounted,

- said building element (1) is mounted from the base of the roof (51) and upwards in a horizontal and floating course of butt joints (52), whereby said rebate (4) of said panel layers (3) of adjacent building elements (1) are overlapping,

- said building element (1) is gradually covered with laths (23) and spacers (22) as said building elements (1 ) are being mounted,

9. A method for mounting said building element (1), according to any of the claims 1 to 7, as a wall construction (30), c h a r a c t e r i s e d in that

- the buildings wall studs (31), braces, window sills and/or door openings are erected,

- said building element (1) is mounted on the outside and/or the inside of said wall studs (31) from the sill and upwards, in a horizontal and floating butt joint (52) course, whereby said rebate (4) of said panel layers (3) of adjacent building elements (1) are overlapping

- work of said wall construction (30) is finished.

10. A method according to any of the claims 8 or 9, c h a r a c t e r i s e d in that, said underroof and/or said wall is made air-/water-proof by: ~ arranging one part of said overlapping edge part of (5) said surface layer (2) over a juxtaposed building element (1), and arranging another part of said overlapping edge part (5) of said surface layer (2) over a subjacent building element (1),

- removing the cover of said adhesive tape on said overlapping edge part (5), thereby fastening the surface layer (2) of one building element to a juxtaposed and/or a subjacent building element (1).