WO2005081651A2

WO2005081651A2 - Housebuilding, wall element and method related thereto

Info

Publication number: WO2005081651A2
Application number: PCT/SE2005/000289
Authority: WO
Inventors: Sten Engwall; Per-Åke ENGVALL
Original assignee: Sten Engwall
Priority date: 2004-02-26
Filing date: 2005-02-25
Publication date: 2005-09-09
Also published as: WO2005081651A3; EP1733101A2; SE0400462D0; SE528246C2; SE0400462L

Abstract

The invention relates to a building that has at least one delimiting part, such as a wall or a ceiling. The delimiting part includes a first layer (1) and a second layer (2) with a space (4) between the layers. According to the invention, the delimiting part is provided with liquid delivery means (5) that function to deliver liquid to said space for a fire fighting purpose. The invention also relates to a wall element of a corresponding nature, and to a fire fighting method.

Description

HOUSEBUILDING, WALL ELEMENT AND METHOD RELATED THERETO

Field of invention According to a first aspect the present invention relates to a building that includes at least one delimiting part which has at least one first and one second layer with a space between said layers. The delimiting part may be an outer wall, an inner wall or a floor structure. According to a second aspect the invention relates to a building wall element that includes at least one first layer and at least one second layer with a space between said layers. According to a third aspect the invention relates to a method of fighting fires in a building that includes at least one wall which has at least one first layer and at least one second layer with a space between said layers.

Background of the invention Serious fires develop as a result of the "explosion" of combustion gases. The hot gases cause the fire to spread rapidly. The fire brigade is often unable to reach the site of the fire before the fire has already reached a temperature of about 450 degrees C, i.e. the temperature at which the seriousness of the fire commences. The aim of those involved in fighting a fire is to lower the temperature to a level below the aforesaid temperature with the aid of water. This takes a long time to achieve, due to the large volume of combustion gases that has had time to develop. The fire also has time to spread still further during the initial stage of dousing the fire with water. When the combustion gases explode, the ambient air will be depleted of oxygen, which can lead to fatalities, either alone or in combination with the heat generated by the fire. It is therefore desirable that the fire can be prevented from reaching said temperature at an early stage. It is known to install sprinklers that will extinguish a fire at an early stage. A sprinkler system that is activated by smoke or heat for instance is able to react quickly. Sprinklers primarily douse all loose articles with water, therewith delaying spreading of the fire. However, experience has shown that sprinklers are unable to deal with a fire successfully in all situations. The object of the present invention is partly to provide a sprinkler system that has a greater fire fighting efficacy than conventional sprinkler systems, and also to enable more cost effective installation of fire fighting equipment.

Summary of the invention According to the first aspect of the present invention, this object is achieved by virtue of the fact that the delimiting part of a building of the type defined in the preamble of claim 1 includes the special feature that the delimiting part is provided with liquid delivery means adapted to deliver liquid to the space between said layers, which first layer is a surface layer of water absorbing material and which second layer is an insulating layer of hygrophobic material. Because the liquid, which is normally, although not necessarily, water, is delivered to a space between two layers in a wall the actual wall will be saturated with water. The heat from the fire will therewith be consumed to a large extent by vaporization of the water delivered to the wall interior. Thus, in principle, the water is delivered to the inside of the wall and therewith ensures effective lowering of the temperature and therewith increase the possibility of mastering development of the fire, as distinct from the effect afforded by a typical sprinkler system. Another important benefit afforded by liquid delivery in accordance with the invention is that the delivery arrangement can be integrated with the actual design of the building in a cost effective fashion and may constitute a system which is present in the wall elements from which the walls of the building are built from the very beginning. The building may, beneficially, be provided with liquid delivery means for internal dousing of all the walls of the building with water, primarily the vertical walls but also floor and ceiling structures. It may sometimes suffice to provide only a part of the walls with liquid delivery means. Because the water is delivered to the inside of a layer that forms an outer layer, the liquid will be exposed close to the heat to be reduced, at the same time as its effect is most urgently required in connection with the outer layer of the wall. When the outer layer is comprised of such material it will be able to absorb a large amount of water, therewith providing a significant cooling effect and also enabling the water to be spread effectively throughout the extension of the outer layer as a whole. Because the water is absorbed by the layer, the risk of uncontrolled collection of large quantities of water is avoided and therewith risk of water damage reduced. By outer layer is meant in this case a wall layer that constitutes a structural component of the wall. Thus, the term surface layer does not refer to wall paper or paint normally applied to the sheets that cover the structural surface layer. According to one preferred embodiment of the invention, the material included in the surface layer is gypsum or a mixture of wood fibers and gypsum in sheet form. Gypsum is a material that has effective absorption properties. However, a mixture of wood fibre and gypsum is particularly beneficial, since such a mixture combines high absorbency with properties that are also beneficial from other aspects. According to another preferred embodiment of the invention, the first layer is disposed on the inner surface of an outer wall. It is primarily the inwardly facing sides of the outer walls where dousing with water is important in order to effectively prevent the fire from spreading. According to another preferred embodiment of the invention said second layer includes a cellular plastic material. Blocks of cellular plastic combine a number of properties that are beneficial in the present context. It affords good building economy, has good properties and does not have the tendency to suck in water. According to another preferred embodiment of the invention, the second layer has profiled elements which function to hold the structural elements of said second layer together, these profiled elements having parts that extend outside the surface of the second layer that faces towards the first layer against which parts of the second layer rest such as to form said interspace. This arrangement is highly beneficial since it exploits the possibility of using the outwardly projecting parts of the profiled elements to provide a well defined interspace. The use of profiled elements of this kind to join together building elements is, in itself, a beneficial building method. These profiled elements are here used for an additional function. Reference is made to 0000/2643 in this regard. According to another preferred embodiment of the invention the liquid delivery means is disposed in the upper part of the wall, preferably adjacent its upper edge. In this case, the force of gravity is used to distribute the liquid over a major part ofthe wall in a vertical direction. This benefit is, of course, most manifest when the liquid delivery means is disposed adjacent the upper edge of the wall, therewith dousing the whole of the wall in a vertical direction. The use of gravity for distributing the dousing water reduces the need to ensure that the water is delivered at a given pressure. According to another preferred embodiment of the invention the liquid delivery means includes a pipe that includes a plurality of openings along its length. A pipe of this nature positioned horizontally will effectively distribute the water readily in the horizontal extension of the wall. The pipe may, of course, be orientated obliquely and does not exclude the presence of a vertical pipe. According to another preferred embodiment, the building is provided with a detector for detecting a fire indicating parameter, such as temperature or the presence of smoke, said detector being adapted to initiate delivery of liquid from said means in the event of a given value of said parameter being exceeded. There is therewith obtained an automatic system for triggering liquid dousing so as to eliminate the need for manual activation. According to another preferred embodiment a liquid tank is mounted at a high height in the building and can be connected to the liquid delivery means. This enables the delivery of water to be ensured in a simple fashion and be free from dependency on the normal water supply system of the building. According to another preferred embodiment the wall has integrated therewith a base part which consists of concrete. Wall elements that have an integrated base part are known to the art from EP954654, to which reference is now made. A thus constructed wall is an expression for a rational construction concept based on the principle of prefabrication. A wall according to the invention that incorporates a sprinkler is also an expression for the same prefabrication principle from a given aspect. The sprinkler system according to the invention is therefore particularly beneficial in connection with said wall type having an integrated base and, in an overall perspective, consists in the integration of different types of functions in a prefabrication stage. The object concerning the second aspect of the invention is achieved by providing a wall element according to the preamble of claim 13 with liquid delivery means for delivering liquid to said interspace, which surface layer is a surface layer of water absorbing material and which second layer is an insulating layer of hygrophobic material. The inventive wall element constitutes a prefabricated unit that is suitable for constructing a building according to the present invention and also affords corresponding benefits. In addition, a wall element of this kind enables the provision of a prefabricated component that has already been prepared for the sprinkler system to which the invention relates. The ability to construct the building with elements that have been thus prepared implies rational and cost-effective production. According to preferred embodiments of the inventive wall element said element includes features that enable it to form a wall or a part of a wall in a building constructed in accordance with the invention and the preferred embodiment of the building. This affords benefits of a kind corresponding to the benefits afforded by the preferred embodiments of the inventive building structure as recited above in connection with the description of said embodiments. The object concerning the third aspect of the invention has been achieved by means of a method according to the preamble of claim 14 and comprising the particular step of delivering liquid to the space between said layers in response to an indication of fire in the building. According to preferred embodiments of the inventive method, the method is applied in a building constructed in accordance with the invention or in accordance with the invention or in accordance with any of the aforesaid embodiments of the building. The inventive method and the preferred embodiments afford benefits of a kind corresponding to the benefits recited above with regard to the inventive building structure and the preferred embodiments thereof recited above. The invention will now be explained more specifically with the aid of the following detailed description of beneficial embodiments thereof and with reference to the accompanying drawings.

Brief description of the drawings Figure 1 is a sectioned view of part of a wall in one exemplifying embodiment of the invention; Figure 2 is an enlarged sub-section taken on the line ll-ll in figure 1 ; Figure 3 is a side view of a part shown in figure 1 ; and Figure 4 is a diagrammatic illustration of a building according to the invention.

Description of beneficial embodiments Figure 1 is a sectioned view of the upper part of a wall according to one embodiment of the invention. In this case, the wall is an outer wall. It has an outwardly facing surface covering 3, which may consist of plaster, bricks or paneling. The covering 3 has located inwardly thereof an insulating layer 2 which may consist of cellular plastic blocks. Located on the inside of the wall is an inner layer 1 which may consist of sheets of gypsum or sheets of a mixture of gypsum and wood fibre, for instance the Finish sheet SASMOX consisting of hard compacted wood-fibre and gypsum pulp. Located between the layer 1 and the insulating layer 2 is a gap 4 which will conveniently have a width in the range of 1-10mm. A pipe 5 extends at the upper end of the gap at right angles to the plane of the drawing. The pipe forms a water delivery means and is provided with a number of openings along its length, these openings conveniently facing downwards. The perforated pipe may, e.g., be made of copper or may consist of a plastic pipe of the kind intended for electric wires. Figure 2 is an enlarged sub-sectioned view taken on the line 11-11 through the wall in figure 1 and illustrates an example of how the inner wall layer 1 may be fastened to the insulating layer 2 such as to obtain a gap or interspace of specific width. The insulating layer 2 is comprised of cellular plastic blocks 2a, 2b, which are held together by vertical steel posts 6 that have a generally Z-shaped profile. The web 9 of the Z-profile is located at the place where the blocks meet, and the legs 7a, 7b of the profile abut against respective side surface of the cellular plastic blocks 2a,

2b on respective sides of the layer 2. Each leg 7a, 7b is terminated with a hook 8 which enters into a groove in respective blocks, therewith holding the blocks 2a, 2b in the layer together. The Z-profile 6 has a material thickness of 1.8mm. Thus, part of the Z-profile 6, i.e. the leg 7a, will project out from the inside of the insulating layer 2 to a corresponding extent. The sheet 1 is secured by being fixed at the legs 7a of the Z-profiles. There is thus created an interspace between the sheet 1 and the insulating sheet of 1.8mm. Figure 3 is an enlarged side view of part of the pipe in figure 1 and illustrates how the pipe 5 may be provided on the underside of the pipe with a number of holes 10 through which water can be injected into the space 4 formed between the sheet 1 and the insulating layer 2. Figure 4 is a diagrammatic illustration of a building provided with a sprinkler system according to the present invention. A water tank 11 is mounted at a high height in the building. The tank may, for instance, be comprised of neoprene rubber. The tank has connected thereto a system of conduits 12 which include vertical pipes 5a, pipes 5b that extend horizontally parallel with the plane of the drawing, and pipes 5c that extend at right angles to the plane of the drawing. The conduit system also includes pipes 5d that are inclined to the plane of the drawing. The conduit system is, of course, adapted to the appearance of the building and also to how its walls and floors extend. A complete system may include a pipe that extends along the upper edge of each wall including outer walls and inner walls in each floor or storey of the building, on the underside of each floor structure and along the sloping roof surfaces. The extent of the conduit system, may, of course be limited to solely certain walls and/or ceilings. The building may be equipped with one or more detectors 13 for detecting temperature and/or smoke development. Each sensor is signal-connected to a valve 14 adjacent the water tank 11 , said valve being controlled by signals from the detectors or sensors 13. As an alternative or as a supplement to the water supply from the tank 11, the system may be equipped with a connecting pipe 15 adapted to allow the connection of an external hose, e.g. from a fire engine. When a fire is indicated by a sensor 13, a control signal is sent from the sensor to the valve 14 which then opens, wherein the conduit system 12 is filled with water from the tank 11 gravitationally. The water is ejected through the holes 10 in respective pipes and therewith reaches the space 4 formed between the layers 1 and 2. When the surface layer 1 is comprised of gypsum or a gypsum/wood fibre mixture, it will be hygrophobic and will suck-in water. The cellular plastic insulating layer 2 is also hygrophobic and does not therefore take-up water ?. Consequently, the surface layer facing towards the space in which the fire burns becomes water impregnated. The liquid present in the sheet 1 is vaporized by the heat from the fire, therewith achieving a highly effective reduction in temperature so as to make spreading of the fire difficult. In the example illustrated in figures 1 and 2, water is delivered to an interspace inwardly of a surface layer that faces in towards the building. It will be apparent that a corresponding arrangement can also be provided at the outwardly facing surface layer 3. This may be appropriate when it is feared that a fire may occur on the outside of the building. The system may, of course, be controlled more selectively than has been described above. For example, the indication of a fire from one of the sensors may generate a control signal which causes only a part of the pipes in the building to be activated for the delivery of water, with the aid of appropriately disposed valves.

Claims

1. A building that includes at least one delimiting part, such as a wall or a ceiling, wherein the delimiting part includes at least one first layer (1) and at least one second layer (2) with a space (4) between said layers, characterized in that the delimiting part is provided with liquid delivering means (5) adapted to deliver liquid to said space (4) which first layer is a surface layer of water absorbing material and which second layer is an insulating layer of hygrophobic material.

2. A building according to claim 1 , characterized in that said first layer (1) is comprised of sheets of material that include gypsum or a mixture of gypsum and wood fibers.

3. A building according to any one of claims 1 -2, characterized in that said first layer (1) is a surface layer applied to the inside of an outer wall.

4. A building according to any of claims 1-3, characterized in that said second layer includes cellular plastic.

5. A building according to any one of claims 1 -4, characterized in that said second layer (2) includes profiled elements (6) for holding together the building elements (2a, 2b) of said second layer (2), wherein the profiled elements (6) have parts (7a) which extend beyond the surface of the second layer (2) facing towards the first layer and against which parts (7a) of the first layer (1) abut such as to form said interspace (4).

6. A building according to any one of claims 1 -5, characterized by liquid delivery means (5) disposed at the upper part of the delimiting part, preferably adjacent its upper edge.

7. A building according to any one of claims 1 -6, characterized in that the liquid delivery means includes a pipe (5) that has a plurality of openings (10) disposed along its length.

8. A building according to any one of claims 1-7, characterized in that the building is equipped with at least one detector (13) which functions to detect a fire indicating parameter, such as a high temperature or the presence of smoke for instance, wherein the detector is adapted to initiate delivery of said liquid by said means (5) when a given value of said parameter is exceeded.

9. A building according to any one of claims 1-8, characterized by a liquid tank (11) mounted at a high height in the building, wherein the tank includes means for connection to the liquid delivery means (5).

10. A building according to any one of claims 1-9, characterized in that the liquid delivery means (5) is connected to a conduit system (12) that includes means (15) for connection to an external mobile liquid source.

11. A building according to any one of claims 1-10 characterized in that the delimiting part is a wall that includes a base part which is integrated with the wall and which consists generally of concrete.

12. A building wall element that includes at least one first layer (1) and one second layer (2) with a space (4) between said layers, characterized in that the wall element includes liquid delivery means (5) for the delivery of liquid to said space (4) which first layer is a surface layer of water absorbing material and which second layer is an insulating layer of hygrophobic material.

13. A wall element according to claim 11 , characterized in that the wall element includes features that enable it to constitute a wall or a part of a wall in a building according to any one of claims 1-11.

14. A method of fighting a fire in a building that includes at least one delimiting part, such as a wall or a ceiling, wherein the delimiting part includes at least one first and one second layer with a space between said layers which first layer is a surface layer of water absorbing material and which second layer is an insulating layer of hygrophobic material, characterized by delivering liquid to said space in response to an indication of a fire in the building.

15. A method according to claim 14, characterized by applying the method in a building according to any one of claims 1-11.