METHOD OF MANUFACTURING A PREFAB CONSTRUCTION ELEMENT

Abstract

The invention relates to a method of manufacturing a prefab construction element (11), preferably a load-bearing element, for frame construction, such as wood frame construction, comprising the steps of providing a roofing, flooring or wall panel (2), which panel (2) comprises an enclosure (3), providing a fungus and a substrate, introducing or preparing a mixture (10) of the fungus and the substrate, in the enclosure (3) and allowing the fungus to grow to form a network of hyphae through the mixture (10) and into the walls (4-7) of the enclosure (3) to form a mycelium composite, and drying the composite while it remains in the enclosure (3) of the panel (2).

Claims

1. A method of manufacturing a prefab construction element for frame construction, comprising the steps of: providing a roofing, flooring or wall panel, which panel comprises an enclosure, providing at least one fungus and a substrate, introducing or preparing a mixture of the at least one fungus and the substrate, in the enclosure and allowing the at least one fungus to grow to form a network of hyphae through the mixture and into the walls of the enclosure to form a mycelium composite, and drying the composite while it remains in the enclosure of the panel.

2. The method according to claim 1, wherein the mixture is introduced in a layer having a thickness of at least 15 centimeters.

3. The method according to claim 1, wherein the panel is made of wood, fiberboard, plywood, or other cellulose based material.

4. The method according to claim 1, wherein the mixture is introduced into the enclosure in the form of bulk or in the form of blocks.

5. The method according to claim 1, further comprising the inclusion of reinforcements in the mixture and/or the inclusion of chunks of mycelium composite in the mixture.

6. The method according to claim 1, wherein the at least one fungus is selected from the group consisting of Pleurotus ostreatus, Pleurotus eryngii, Stropharia Rugosoannulata, Trametes versicolor, Ganoderma Lucidum, Phanerochaete chrysosporium, Bjerkandera adusta, Lentinula edodes, Pycnoporus cinnabarinus, Pycnoporus sanguineus, Grifola frondosa, Schizophyllum commune, Neolentinus lepideus, and Heterobasidiom annosum.

7. The method according to claim 1, wherein during at least part of the growing of the hyphae, the enclosure is covered and/or the temperature of the mixture is maintained in a range from 15 to 24 degrees Celsius.

8. The method according to claim 1, wherein the growth of the at least one fungus is stopped by means of heating, reduced pressure, freezing, radiation and/or drying.

9. The method according to claim 1, wherein a nutrient is added to the mixture.

10. A prefab construction element for frame construction, comprising a roofing, flooring or wall panel, which panel -comprises an enclosure, which enclosure contains a mixture of at least one fungus and a substrate, wherein a network of hyphae has formed through the mixture and into the walls of the enclosure to form a mycelium composite.

11. The prefab construction element according to claim 10, comprising a layer of the mixture having a thickness of at least centimeters and/or containing chunks of mycelium composite and/or cavities.

12. The prefab construction element according to claim 10, wherein the panel is made of wood, fiberboard, plywood, or other cellulose based material.

13. The prefab construction element according to claim 10, wherein the panel further comprises rafters dividing the enclosure in sections, and roof slabs and/or vertical battens fixed to the panel and optionally horizontal battens fixed to the vertical battens.

14. The prefab construction element according to claim 13, wherein the rafters have a thickness less than 25 mm.

15. The prefab construction element according to claim 10, wherein a ratio of the weight of the panel and the weight of the mixture is smaller than 0.6.

16. The method according to claim 1, wherein a ratio of the weight of the panel and the weight of the mixture is smaller than 0.6.

17. The method according to claim 2, wherein the panel is made of wood, fiberboard, plywood, or other cellulose based material.

18. The method according to claim 2, wherein the mixture is introduced into the enclosure in the form of bulk or in the form of blocks.

19. The method according to claim 3, wherein the mixture is introduced into the enclosure in the form of bulk or in the form of blocks.

20. The method according to claim 2, further comprising the inclusion of reinforcements in the mixture and/or the inclusion of chunks of mycelium composite in the mixture.

Description

[0037] The invention will now be explained in more detail with reference to the figures, which schematically show an embodiment according to the present invention.

[0038] FIG. 1 is an isometric view of a traditional roofing panel and a roofing panel according to the present invention, both having an enclosure.

[0039] FIGS. 2 and 3 show the panels of FIG. 1 wherein respectively glass wool and a mixture of substrate and fungus has been introduced in the enclosure, in the form of bulk (FIG. 2) and in the form of blocks (FIG. 3).

[0040] FIG. 4 is an isometric view of a prefab construction element according to the present invention.

[0041] FIG. 1 shows, on the left-hand side, a traditional roofing panel 1 and, on the right-hand side, a roofing panel 2 according to the present invention. Both panels 1, 2 have an enclosure 3 defined by a bottom wall 4, made e.g. of wood or fiberboard, side walls 5, and upper and lower end walls 6, 7, all made e.g. of wood. In this example, the upper end wall 6 forms a headboard that is at an inclination and that, once the panel is installed on a roof, forms the apex of the roof (inner) construction and supports e.g. a ridge beam and/or ridge tiles. The lower end wall 7 forms a gutter board.

[0042] The side walls 5 are in effect rafters that play a major role in providing strength and stiffness to the panel 1, 2. As shown in FIG. 1, the traditional panel 1 comprises a total of five rafters 5, two on the sides (co)defining the enclosure 3 of the panel 1 and three inside the enclosure, dividing the enclosure into four sections. The panel 2 according to the present invention comprises a total of three rafters 5, two sides (co)defining the enclosure 3 of the panel 2 and one inside the enclosure dividing the enclosure into two sections.

[0043] After providing the panel, a substrate, such as a blend of hemp, foliage, and sawdust was mixed with a fungus (inoculum), for instance Pleurotus ostreatus, optionally at least one nutrient, such as oatflakes, and water.

[0044] FIGS. 2 and 3 show the panel 2 according to the present invention with a mixture 10 of substrate and fungus having been introduced in the enclosure 3, in the form of bulk (FIG. 2) and in the form of blocks (FIG. 3).

[0045] After the mixture was introduced into the sections of the enclosure, the enclosure was covered, e.g. with an impermeable foil or tarpaulin, and the temperature of the mixture was maintained in a range from 15 to 24° C., for example 20° C. The fungus was allowed to grow, e.g. for a period in a range from 50 to 120 hours, preferably in a range from 70 to 110 hours, for example 100 hours, to form a network of hyphae through the mixture and into the walls 4-7 of the enclosure 3 to form a mycelium composite.

[0046] When the mycelium composite was considered at or near optimum, in terms of strength, stiffness and durability in a dried state, the fungus was killed by heating and drying the prefab construction element and the mycelium composite in it.

[0047] To extend the comparison of the construction element of the present invention with traditional construction elements, FIGS. 2 and 3 show, on the left-hand side, the traditional panel filled with glass wool as an insulating material. The panels 1, 2 have the same external dimensions and both fulfil official requirements (building codes) for strength, stiffness, and insulation. In a specific example, the traditional panel 1 has five rafters 5 having a height of 250 mm and a thickness of 32 mm, whereas the panel 2 according to the present invention has three rafters 5 having a height of 250 mm high and a thickness of 18 mm, saving more than 60% on the wood of the rafters alone.

[0048] FIG. 4 shows a prefabricated construction element 11 wherein the panel 2 comprises, in addition to the rafters 5 forming the side walls and dividing the enclosure 3 in sections, vertical battens 12 fixed to the panel 2 and optionally horizontal battens 13 fixed to the vertical battens 14, thus ready to be installed in a wood frame building. Because the mycelium composite is liquid water repellent and water vapour permeable, the foil covering the glass wool in the traditional construction element can be omitted in the construction element according to the present invention.

[0049] The invention is not restricted to the above-described embodiments, which can be varied in a number of ways within the scope of the claims, and, for instance, applies similarly advantageously in construction elements for floors and walls.