Technical Field

The present disclosure relates to a house foundation system, and to a method for forming a house foundation and a method for forming a floor structure.

Background

Foundations for construction of buildings are traditionally formed by a concrete ground plate arranged on a layer of insulating material, such as cellular plastic, in an excavation. The layer of cellular plastic may sometimes need to be as thick as 400 mm to provide necessary insulating properties. The concrete ground plate, casted on site on the insulating material, may in such cases have difficulties to dry and cure. The drying can only be performed upwards due to the presence of cellular plastic below, and the drying and curing may take long time.

A prefabricated concrete ground plate would solve problems

concerning drying and curing on site, but would be difficult to arrange to provide a leveled foundation.

Consequently, there is a need for a facilitated way of forming a house foundation regarding time and effectiveness when it comes to drying, curing and construction. Summary

It is an object of the present invention to provide an improved solution that alleviates the mentioned drawbacks with present devices. Furthermore, it is an object to provide a system of and a method of forming a house foundation as well as a method for forming a floor structure.

This is realized according to a first aspect of the invention by providing a house foundation system comprising a foundation frame for arrangement on an excavation bottom. The foundation frame comprises a plurality of height- adjustable support members which are adjustable for providing a leveled foundation frame on an uneven excavation bottom.

By providing a house foundation system with a foundation frame having height-adjustable support members, the frame may be prefabricated and arranged in an excavation and still provide a leveled foundation. The need for an onsite casted concrete ground to get a leveled foundation is thereby avoided. The time needed for providing a ready, dried house foundation may thereby be significantly shortened. In an uneven excavation, the support members may stand directly on the excavation bottom or on support plates arranged on the excavation bottom. Each support member may be configured to provide a height-adjustability of a section of the frame which may be adjusted to provide a leveled upper surface of the frame. The frame may in one embodiment comprise at least four support members, each arranged at a corner, or adjacent to a corner, of the frame. The frame may further comprise additional support members on other sections of the frame to provide a more accurate height-adjustability to level the frame.

In one embodiment, the foundation frame comprises at least four height-adjustable support members arranged in each corner of the foundation frame. By having a plurality of height-adjustable support members in each corner, more specifically four height-adjustable support members, the foundation frame may be tilted and adjusted in several degrees of freedom. The foundation may thus be adjusted length-wise as well as cross-wise relative to the frame. In one embodiment, each height-adjustable support member may comprise a threaded spindle or screw arranged in a

corresponding threaded hole in the frame. The spindle may be rotated to raise or lower the frame when standing on ground. The holes may extend through the frame. A threaded spindle arranged in such hole may then extend both below and above the frame when standing on ground. The spindle may thereby be accessed from above for height-adjustment when the foundation frame is arranged in an excavation. The hole may be made in the pre-casted frame. In a further embodiment, the foundation frame may be made of light ballast concrete. The ballast in the light ballast concrete may be foam glass, lightweight-expanded aggregate, pumice or the like, such as other ceramic material. Such light ballast concrete may provide insulating properties to the frame and the house foundation system.

In another embodiment, the house foundation system may comprise an insulating and draining granulate material. Such material may be used for filling the frame when arranging the house foundation system in an

excavation. Such insulating and draining granulate material may be foam glass, lightweight-expanded aggregate, pumice or the like. Such materials may both provide an insulating function and a draining function to the house foundation. Such material may further be nonorganic, thereby providing a house foundation system free from organic material.

In a further embodiment, the foundation frame may be formed by frame modules connected by connection elements. A frame in modules may be easier to arrange on an excavation bottom. Connection elements may be arranged at the ends of the modules to interconnect modules. The connection elements may be integrated with the location of the support members.

In a further embodiment, at least one of the frame modules comprises a plurality of support members, each support member associated with a corner of the frame module. By arranging one height-adjustable support member in each corner of a frame module, each frame module may be adjustable as required on an uneven excavation. Each support member provides adjustability for each corner and results in movability in several degrees of freedom.

The house foundation system may further comprise at least one channel system for drying the foundation when arranged in an excavation. The drying may be achieved by providing a controlled pressure flow of for instance air in the channel system, which may be achieved by using any or a mixture of the following: underpressure, overpressure, balanced pressure, varying pressure. The channel system may comprise a channel formed in the granulate material, a perforated tube or hose arranged in the granulate material. The channel system may be connected to a dehydrator arrangement configured to provide an underpressure in the channel system and thereby enable extraction of humidity in the foundation. Humidity in the foundation may thereby be drawn towards the channel system and extracted through the channel system. In one embodiment may a first section of the channel system be configured to provide a flow of dry air into the foundation, and a second section of the channel system may be configured to extract air from the foundation, thereby extracting humidity in the foundation. The channel system may as well, or alternatively be arranged to provide dry air to the foundation in order to achieve a more quick and efficient drying procedure.

According to a second aspect of the invention, a method for forming a house foundation is provided, wherein the method comprises the steps of arranging a foundation frame on an excavation bottom, filling the excavation with an insulating and draining granulate material, and providing a ground plate supported by said foundation frame. Such method may provide a way of forming a house foundation which without organic material provides good insulation, draining and stability properties. The foundation frame and/or the ground plate may be prefabricated, thereby facilitating and speeding up the foundation formation.

In one embodiment, the granulate material may be foam glass, lightweight-expanded aggregate, pumice or the like. Such materials have good insulating and draining properties. The materials are further nonorganic, which is an advantage when it comes to preservation of the foundation over time.

In another embodiment, the method further comprises a step of arranging a capillary barrier on the excavation bottom. The capillary barrier may be arranged for preventing humidity from the ground to reach the granulate material on top of the capillary barrier.

In a further embodiment, the method may comprise a step of providing at least one channel system below the granulate material for drying the foundation using a controlled pressure flow of a gaseous medium. Controlled pressure may be achieved by using any of the following: underpressure, overpressure, balanced pressure, varying pressure. By allowing the pressure flow to be controlled, a pressure flow suitable for the specific material may be provided. The gaseous medium may be air. The channel system may be configured for connection to a dehydrator arrangement. The channel system with the dehydrator may be arranged for extraction of humidity in the foundation using underpressure in the channel system. The method for forming a house foundation may further comprise a step of extracting humidity from the house foundation by providing underpressure in said channel system. By varying pressure it is meant that the pressure may be varying during a period of time, such as pulsating in different positive pressure rates, or even varying between positive and negative pressure.

In one embodiment, the ground plate may comprise light ballast concrete. The ballast in the light ballast concrete ground plate may be foam glass, lightweight-extracted aggregate, pumice or the like. A ground plate of such material may provide good both insulating and draining properties.

Alternatively, the ground plate may be made of foam concrete.

In another embodiment, the method may further comprise a step of providing a support casting of the foundation and/or the ground plate. After the granulate material has been provided in the excavation, and packed therein, the foundation frame may be fixed in place in the excavation. The ground plate may then be fixed in position on the foundation frame by providing a support casting between the ground plate and the foundation frame. The ground plate may thereby be fixed in position relative to the frame. The support casting may be provided using light concrete, foam concrete or light ballast concrete using foam glass, lightweight-extracted aggregate or pumice as ballast. The support casting may be provided such that it extends through couplings between frame modules. The support casting may further extend towards the ends of support members by which the foundation frame stands on the excavation bottom. Further, support casting may be provided in a space between the granulate material within the foundation frame and the ground plate arranged on the foundation frame. In a further embodiment, the foundation frame may comprise a plurality of height-adjustable support members, adjustable to provide a leveled foundation frame on an uneven excavation bottom. The method may then further comprise a step of adjusting the support members to provide a leveled foundation frame arranged on the excavation bottom. Such frame may provide arrangement in a leveled manner using the height-adjustable support members, thereby providing a facilitated house foundation forming method.

According to a third aspect of the invention, a method for forming a floor structure is provided comprising the steps of providing a slab,

providing an insulating and draining granulate material on top of said slab, and providing at least one channel system in the layer with granulate material for drying of the floor structure using a controlled pressure flow of a gaseous medium in the channels.

The slab may be arranged where the floor structure is to be built. The slab may be a prefabricated concrete plate or a concrete plate cast on site. Alternatively, the slab may be a steel slab, wooden slab, or any other suitable material. The granulate material may be provided on top of the slab. The channel system may comprise a channel formed in the granulate material, a perforated tube or hose arranged in the granulate material. With a floor structure provided with the channel system, the process of drying and curing the granulate material may be sped up since the channel system may help extract the moisture from the wet or humid building material. This may result in a more evenly dried structure, as well as the drying times may be significantly reduced. The gaseous medium may be air. The dehydration may be done providing a controlled pressure flow in the channels such that moisture in the floor structure, and specifically in the granulate material may be extracted through the channels. The channel system may be arranged in the lower region in the layer of granulate material, the moisture may be transported downwards, leaving the upper surface of the granulate material dry in order to allow floor installation more quickly without compromising the quality of the floor. The floor structure according to the method may be suitable for any floor. It may be a floor structure intended to be used inside a building such as a ground foundation or a floor above ground. It may also be suitable for outdoor floors, such as ground terraces, roof terraces and balconies and the like.

In one embodiment, the granulate material may be foam glass, lightweight-expanded aggregate, pumice or the like. Such materials may both provide an insulating function and a draining function to the floor structure. Such material may further be nonorganic, thereby providing a floor structure free from organic material.

In one embodiment, the slab plate may be one of the following: a prefabricated concrete slab plate, a steel slab, a wooden slab.

By using a prefabricated slab, the building times may be reduced. A concrete plate may be of light ballast concrete or the like. Any of the mentioned may also be suitable in an outdoor floor structure.

In another embodiment, the slab plate may be provided by casting a concrete slab.

In one embodiment, controlled pressure may be achieved by using any of the following: underpressure, overpressure, balanced pressure, varying pressure. By controlled pressure, it is meant that the pressure in the channel system may be controlled or manoeuvred by a user, for instance via a control device. By controlling the pressure flow in the channels, the drying and curing may be adapted to suit the specific material and environment. The pressure may be controlled depended on the moisture level and the type of material. For instance, the dehydration may be achieved via a dehydrating suction arrangement causing underpressure in the channels such that the moisture may be transported downwards in the structure and extracted through the channels.

The provided suction may cause the moisture to transport downwards towards the channels and thereby allow the slab cure more quickly than a floor structure without any dehydrating function. By varying pressure it is meant that the pressure may be varying during a period of time, such as pulsating in different positive pressure rates, or even varying between positive and negative pressure. By doing this, the surface of the granulate material may dry more quickly so that floor installation may proceed faster. The dehydrating system may be running during subsequent floor installation in order to ensure completely dry floor structure.

In yet another embodiment, the channel system may be provided with an airing function for ventilating the floor structure. The channel system may be connected to an arrangement providing dried air to the floor structure through the channel system. By doing this, the air may flow in the channels, causing the moisture in the floor structure to vent out more easily. Since more than one channel system may be provided, different channel systems may be arranged for different purposes in the floor structure. For instance, one channel system may be arranged to provide a dehydrating function while a second channel system may be arranged to provide dry air. The different functions of the channel systems may thus interact in order to provide a more efficient drying of the floor structure. A quicker drying process may allow quicker floor installation. The systems may be running simultaneously and also during subsequent floor installation in order to ensure a completely dry floor structure.

In another embodiment, a concrete screed may be provided on top of said granulate material. By concrete screed it is meant a layer of concrete in order to protect the granulate material. The concrete screed may in some embodiments be of other material than concrete for instance a cement material or another suitable material. The concrete screed may be arranged in order to protect the underlying granulate material.

In yet another embodiment, a moisture barrier may be provided above the concrete screed. Subsequently, a superstructure may be provided above the moisture barrier. The moisture barrier may be a waterproofing membrane or fiber or the like with the characteristics of preventing moisture from penetrating the underlying granulate material from above. The floor structure may be suitable to be arranged outdoors, such as for terrace flooring or the like. When used outside, there may be needed a protective layer such as a moisture barrier to prevent moisture from the outdoor air or rain water from entering the structure. On top of the moisture barrier, a superstructure may be arranged. The superstructure may be any material required, such as earth and grass, a wooden deck or the like. However, the step of providing a superstructure may be optional.

In yet another embodiment, flooring may be provided on top of the concrete screed. For indoor use, it may be suitable to arrange comfortable flooring which may be any floor required for the use of the room.

Any steps according to the method may be performed in any suitable order. Since a floor may be built from the bottom and upwards, it may be suitable to perform steps accordingly. However, it is an alternative that one or more of the mentioned steps are performed in an order different from that chronological order mentioned to provide a prefabricated structure. The method may thus be unlimited to the order of steps. Brief Description of the Drawings

The invention will in the following be described in more detail with reference to the enclosed drawings, wherein:

Fig. 1 is a perspective view of a house foundation system according to an embodiment of the invention,

Fig. 2 is a cross-sectional view of a house foundation system

according to an embodiment of the invention,

Fig. 3 is a cross-sectional view of a house foundation system

according to an embodiment of the invention,

Fig. 4 is a cross-sectional view of a house foundation system

according to an embodiment of the invention,

Fig. 5 is a cross-sectional view of a house foundation system

according to an embodiment of the invention,

Fig. 6 is a cross-sectional view of a house foundation system

according to an embodiment of the invention, and

Fig. 7 is a flow chart of a method according to an embodiment of the invention. Fig. 8 is a cross sectional view of a floor structure according to an embodiment of the invention.

Fig. 9 is a cross sectional view of a floor structure according to an embodiment of the invention.

Description of Embodiments

The present invention will be described more fully hereinafter with reference to the accompanying drawings, in which preferred embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. In the drawings, like numbers refer to like elements.

Figs. 1 -3 illustrate a house foundation system 1 comprising a

foundation frame 10 according to an embodiment of the invention. The foundation frame 10 is arranged in an excavation 2 to form a house

foundation. The foundation frame 10 comprises a plurality of support members 12. The support members 12 are formed by threaded spindles or screws 12 arranged in corresponding threaded holes 14 in the foundation frame 10. See fig. 2. The support members 12 support the foundation frame 10 on the ground in the excavation 2. The bottom surface of the excavation 2 is difficult or impossible to get completely plane. Due to the threaded support members 12 in the threaded holes 14 are the support points of the foundation frame 10 adjustable in height. The support members 10 are located at least at, or adjacent to, the corners of the foundation frame 10. In the illustrated embodiment are support members 12 further located at a midpoint of sides of the foundation frame 10. The position of these support members 12 provides that different parts of the foundation frame 10 may be height-adjusted to provide a leveled upper side of the foundation frame 10. A plurality of support members 12 are grouped together at location along the foundation frame 10. To provide stability of the foundation frame 10 and the support members 12 are all support members 12 placed on a support plate 18 on the excavation bottom.

In the illustrated embodiment is the foundation frame 10 formed by a plurality of frame modules 10a-1 Of. The frame modules 10a-1 Of are in the corners of the frame 10 connected by corner modules 1 1 . At the ends of the frame modules 10a-f are coupling members 16 arranged. Each coupling member 16 is configured for coupling to a corresponding coupling member 16 on another frame module.

The foundation frame 10 further comprises a shoulder 19 at an inner side of the frame 10. The shoulder 19 is, as seen in fig. 2 and further in fig. 6, provided for support of a ground plate 40 of the house foundation system 1 . When the foundation frame 10 has been arranged on the bottom of the excavation 2, and leveled by adjustment of height-adjustable support members 12, the ground plate 40 may be arranged on the shoulder 19 of the foundation frame 10 and thereby be plane. The ground plate 40 may thereby be prefabricated given the size of the foundation frame 10, and still provide a leveled surface of the house foundation system 1 .

The foundation frame 10 is preferably made of foam glass to provide a frame that has an insulating function.

Figs. 4-6 further illustrate the house foundation system 1 , and also the method of forming a house foundation system according to an embodiment of the invention. The foundation frame 10 is arranged in an excavation 2, standing on the support members 12. The support members 12 are further placed on support plates 18 on the ground in the excavation 2.

As seen in fig. 5 is the excavation filled with an insulating and draining granulate material 30. The granulate material 30 is in one embodiment made of foam glass. In another embodiment is the granulate material 30 lightweight- expanded aggregate, pumice or the like. The granulate material 30 is packed in the excavation. The granulate material 30 is provided, and packed, both inside the foundation frame 10 and outside the foundation frame 10, within the excavation 2. When packed in the excavation 2 will the granulate material 30 provide good insulation function as well as a draining function of the foundation. The granulate material 30 is filled up to a level below the level of the shoulder 19 of the foundation frame 10. In one embodiment is the granulate material filled up to a level 30-80 mm below the shoulder 19 of the foundation frame 10, preferably about 50 mm below the shoulder 19. On top of the packed granulate material 30 may a fiber cloth layer be arranged.

Next, as seen in fig. 6, is the ground plate 40 arranged on the shoulder 19 of the foundation frame 10. A space 5 is thereby formed between the granulate material 30 and the ground plate 40. The ground plate 40 is made of light ballast concrete comprising ballast in form of foam glass, lightweight- expanded aggregate, pumice or the like. The ground plate 40 may in another embodiment be made of light concrete or foam concrete. The ground plate 40 may further, instead of being prefabricated and put in place on the foundation frame 10, be casted directly in place on the foundation frame 10 and the granulate material 30.

The final step of forming the house foundation 1 is to provide a support casting for fixating the foundation frame 10 and the ground plate 40. The support casting is performed to fix the ground plate 40 to the foundation frame 10. The support casting is provided in a space 4 between the ground plate 40 and the foundation frame 10. The support casting then extends downwards through the coupling between frame modules 10a-f. The coupling members 16 are thereby fixed to the frame modules at each coupling. The support casting further fixates the foundation frame 10 towards the excavation bottom by filling a space 3 below the foundation frame 10 at which the support members 12 support the frame 10. Further, the support casting may fill the space 5 between the granulate material 30 and the ground plate 40, thereby further fixating the ground plate 40 to the foundation frame 10 and the granulate material 30.

As illustrated in figs. 1 -6, the house foundation system 1 comprises a channel system 20 arranged at the bottom of the excavation 2. The specific channel system 20 is connected to a dehydrator arrangement 22 in order to provide an underpressure in the channel system 20. Dehydration may also be achieved by providing any controlled pressure flow of a gaseous medium, such as air, in the channel system 20 such that extraction of humidity from the foundation be performed, especially from the granulate material 30. The controlled pressure may be achieved from any suitable flow, such as underpressure, overpressure, balanced pressure or varying pressure. Hence, the method of forming a house foundation may comprise a step of providing a controlled pressure flow of for instance air or another gaseous medium in a channel system 20 in the foundation 1 to extract humidity therefrom. The channel system 20 may alternatively be arranged to provide dry air to the foundation for an alternative drying procedure. Another option may be to provide two or more channel systems, wherein one may be connected to a dehydrator arrangement, and the second system provide dry air. The channel systems 20 may thus interact simultaneously for a more efficient drying procedure.

Fig. 7 illustrates a flow chart of a method of forming a house foundation according to an embodiment of the invention. The method 100 comprises a step 1 10 of arranging a foundation frame 10 on the bottom of an excavation 2. The foundation frame 10 comprises, in one embodiment, height-adjustable support members 12 that enable the foundation frame 10 to be height- adjusted to be leveled. The method may then further comprise a step of adjusting the support members to provide a leveled foundation frame 10. The method 100 further comprises a step 120 of filling the excavation 2 with an insulating and draining granulate material 30. The granulate material 30 may for instance be foam glass. The granulate material 30 is provided both inside and outside the foundation frame 10 in the excavation 2. The step 120 may further comprise a step of packing the granulate material 30. Further, the method 100 comprises a step 130 of providing a ground plate 40 on the foundation frame 10. The ground plate 40 can be prefabricated to shorten the time of the forming of the house foundation 1 . Finally, the method comprises an optional step 140 of providing a support casting for fixating the ground plate 40 to the foundation frame 10. The support casting further fixates the foundation frame 10 on the bottom of the excavation 2. The described and illustrated embodiments comprise one foundation frame 10 in one piece or modules for receiving one ground plate 40 thereon. The house foundation system may as well comprise further sections or modules of the foundation frame to form a plurality of frames arranged next to each other or interconnected by sharing frame modules. Foundation frame configurations having various forms may thereby be formed, and thereby also being configured for receiving two or more ground plates thereon. For instance, a foundation frame may comprise a rectangular shaped outer frame section being divided into two portions by an intermediate frame module. The intermediate frame module may thereby be shared by the two portions. The intermediate frame module may further be configured to support two ground plates, one for each portion of the foundation frame, by having two opposite shoulders.

Fig. 8 illustrates a cross sectional view of a floor structure 200 according to an embodiment of the invention. The floor structure in Fig. 8 may be a general type of floor structure 200 typically used inside a building. This type of floor structure 200 may be suitable above ground level. First, there is provided a slab 50 in the bottom of the floor structure 200. Generally, the slab 50 is provided first and may be made of a concrete material. The slab may alternatively be made of other suitable material such as steel or wood. It may be a prefabricated plate. On top of the slab 50, a layer of insulating and draining granulate material 30 may be provided. Inside the layer of granulate material 30, two channel systems 20 are arranged. Preferably the channel systems 20 are arranged before the granulate material 30 is arranged. Fig. 8 illustrates an embodiment using two channel systems 20, wherein a first channel system 21 is connected to a dehydrating arrangement causing suction and underpressure in the channel 21 . A second channel system 22 is connected to an arrangement providing dry air to the floor structure. The two channel systems cooperate to make the drying procedure more efficient and time reducing. Arrows in channel 21 and channel 22 in Fig. 8 give guidance to the flow direction. The granulate material may be cast on top of the slab. On top of the granulate material 30, a concrete screed 60 is provided. Generally the concrete screed 60 may be cast on top of the granulate material 30, but it may alternatively be a prefabricated plate. The concrete screed 60 may typically be arranged to protect the granulate material and to provide a suitable foundation for flooring. The concrete screed 60 may thus be of other material suitable for that function. The next step is to provide flooring 70 on top of the concrete screed 60. The flooring may be any suitable flooring such as wooden boards.

Fig. 9 illustrates another embodiment of a floor structure 200 suitable for outdoor use. In the bottom of the floor structure 200, a slab 50 is provided. The slab 50 may be of a suitable material such as concrete, steel or wood. On top of the slab, an insulating and draining material 30 is provided. The insulating and draining material may be a granulate material. Inside the layer of granulate material 30, two channel systems 20 are arranged such as illustrated in Fig. 8. Preferably the channel systems 20 are arranged before the granulate material 30 is arranged. On top of the granulate material 30, a concrete screed 60 is arranged. The concrete screed 60 may be provided in order to protect the granulate material. The concrete screed 60 may be an onsite cast concrete plate. Further on top of the concrete screed 60, there is a membrane layer such as a moisture barrier 80. The moisture barrier 80 may be provided to protect the underlying layers from moisture penetrating the floor structure 200 from above. On top of the moisture barrier, a

superstructure 90 may be arranged. The superstructure 90 may consist of earth and grass, or for instance a wooden deck. In the drawings and specification, there have been disclosed preferred embodiments and examples of the invention and, although specific terms are employed, they are used in a generic and descriptive sense only and not for the purpose of limitation, the scope of the invention being set forth in the following claims.