Knock-down house and method of building the same

[0002] To use a bungalow made of wood, or a tent made of cloth, for an outdoor facility such as an outdoor accommodation and the like is well-known. However, assembling a bungalow has problems, being bothersome and laborious because (1) metal angles and brackets must be used in assembling the wood materials, and (2) fastening with bolts also is necessary. And although a tent is easy to set up, it also has problems, because a tent lacks good livability because its durability and adiathermancy are poor. Patent Document 1 describes an outdoor facility that has a dome-like shape and that is assembled by joining together a plurality of sections made of foam polystyrene, which is a substance that is light and has good adiathermancy. As a result, a facility made of foam polystyrene has good livability. In addition, foam polystyrene does not generate poisonous gas when it is burned in order to be disposed of, and thus it has the advantage that it does not adversely impact the environment when disposed of. Patent Document 1: International Publication Number WO 01/44593 Disclosure of the Invention Problems in the prior art A knockdown structure assembled by joining together a plurality of sections made of foam polystyrene has the following problems. Mortar is used as a sealant on the surface of foam polystyrene, but sometimes the sealant experiences cracking due to external pressure such as wind, snow, or rain. Although cracks do not undermine the function of the knockdown structure, its exterior appearance diminishes. Taking countermeasures against cracks by thickening the sealant requires much manpower and time, especially when doing so for vertical walls. If the adhesion that bonds the sections together is not sufficient, an unfilled gap -- i.e., a concave part -- can result between the sections that are bonded together. This causes the sealant to have an uneven thickness. The uneven thickness of the sealant causes some parts of the sealant to dry sooner than other parts do. This difference in drying time can result in cracking of the sealant. To protect foam polystyrene against degradation caused by ultraviolet light, paint mixed with titanium oxide powder is applied thereon. However, such paint, which screens out ultraviolet light, easily comes off due to rain and snow. Therefore, maintenance, and sometimes repair, is necessary. There is an assembly method whereby metal beams and bars are attached to the junction between sections to be bonded together, so as to reinforce the connection between the sections. But this assembly method is complex and expensive. Advantageously, embodiments of the invention may provide (1) a knockdown structure that can avoid cracking of the sealant, reinforce the connections of the structure's sections, and improve the livability of the structure, and (2) methods of assembling such a knockdown structure. Means for Solving the Problems In a first aspect, there is provided a method of assembling a knockdown structure, the method comprising the following steps: forming a base by joining a plurality of blocks made of concrete, assembling a body of the structure, which has a predetermined shape, by using a mortar-powder mixed adhesive to join together a plurality of sections that are made of foam polystyrene and that constitute the parts of the structure, with the plurality of sections being arranged in a standing condition on the base, applying an adhesive on a mesh sheet, which includes a woven inorganic fiber, in such a way that the mesh sheet is glued to (i) the places where the sections are joined together, with the adhesive bonding the sections together, (ii) both the standing part of the sections and the corresponding parts of the base of both the exterior and interior faces of the body of the structure, and (iii) the whole circumference of the outer upper surface of the base excluding the parts of the base that contact the standing part of the sections, applying, in a predetermined thickness, a sealant, which is made by dispersing inorganic fiber and mortar powder in a plastic-type paint, on the exterior and interior faces of the structure's body, applying, over the sealant that is on the exterior faces of the structure's body, an exterior paint that is water repellent and that is adapted to screen out ultraviolet light, and applying, over the sealant that is on the interior faces of the body of the structure, a clayey paint that is made of natural substances. In one form of assembling the knockdown structure, the mesh sheet is placed and glued in such a way that it covers almost all of the exterior of the assembled structure's body. In one form of assembling the knockdown structure, the sealant that is applied to the upper half of the interior faces of the structure is covered by the clayey paint that is made of natural substances, and the sealant that is applied to the lower half of the interior faces of the structure is covered by the exterior paint. In one form of assembling the knockdown structure, a modified silicone-plastic paint is used as the exterior paint. In one form of assembling the knockdown structure, diatomite or a whitewash is used as the clayey paint that is made of natural substances. In one aspect, there is provided a knockdown structure comprising: a base formed by joining a plurality of blocks made of concrete, a body including a plurality of sections joined together, the sections made of foam polystyrene and divided into the parts of the body of the structure, which has a predetermined shape, using an adhesive mixed with mortar powder, with the plurality of sections being arranged in a standing condition on the base, a mesh sheet having a woven inorganic fiber arranged in such a way that the mesh sheet covers (i) the places where the sections are joined together, (ii) both the standing part of the sections and the corresponding parts of the base of both the exterior and interior faces of the body of the structure, and (iii) the whole circumference of the outer upper surface of the base excluding the parts of the base that contact the standing part of the sections, a sealant, which is made by dispersing inorganic fiber and mortar powder in a plastic-type paint, is applied on the exterior and interior faces of the structure's body in a predetermined thickness, an exterior paint, which is water-repellent and is adapted to screen out ultraviolet light, applied over the sealant that is on the exterior of the structure, and a clayey paint that is made of natural substances is applied over the sealant that is on the interior of the structure In one form the mesh sheet is arranged in such a way that it covers almost all of the exterior of the structure. In one form, the knockdown structure further comprises; an air-circulation means to circulate, through the sections, the air inside the structure and an air-cleaning means disposed in the flow path of the air that is circulated by the aircirculation means. In one form, the knockdown structure further comprises; an air-circulation means to circulate, through the sections, the air inside the structure, and an air-heating means disposed in the flow path of the air circulated by the aircirculation means. In one form of the knockdown structure, the clayey paint made of natural substances is applied over the sealant that is on the upper part on the interior faces of the of the body of the structure, and the exterior paint is applied over the sealant that is on the lower part of the body of the structure. In one form of the knockdown structure, the exterior paint is a modified siliconeplastic paint. In one form of the knockdown structure, clayey paint made of natural substances is diatomite or a whitewash. In one form of the knockdown structure, flooring material made of foam polystyrene is laid down on the structure's floor. Advantages of the embodiments of Invention The method of assembling the knockdown structure described above may firmly hold the places where the sections are joined together, by using an adhesive to pasting thereon a woven inorganic-fiber mesh sheet, and then applying thereon a sealant, including mortar, in order to fix the joining. As a result, cracking of the sealant and displacement of the sections can be prevented without fail. Also, to increase the strength of the joining it is not necessary to attach metal reinforcing materials to the places where the sections are joined together, and thus the assembly method can be simplified. Further, because the mesh sheet covers the places where the sections are joined together, it helps to flatten any concave parts that might exist in the junctions. Thus, the mesh sheet has an effect of making it possible to paint the sealant in an even thickness. Therefore, cracks in the sealant, which occur due to uneven thicloless, can be prevented. Moreover, because inorganic fiber is mixed into the sealant, the strength of the sealant itself is increased and cracking can be prevented. Degradation of the sections by water and/or ultraviolet light can be prevented because modified silicone paint -- which is an exterior paint that is water repellent and can screen out ultraviolet light rays -- is applied over the sealant on the exterior face of the structure. Thanks to this water repellency, the paint repels rain and snow, and it seldom comes off, which makes the structure's exterior maintenance-free. clayey paint made from diatomite or a whitewash is applied over the sealant of the interior face of the structure. And because diatomite or a whitewash can adsorb or decompose poisonous gas emitted from plywood and the like, the livability of the knockdown structure is improved. In the assembly method described, the mesh sheet is pasted so as to cover the whole of the exterior face of the assembled structure's body, making it possible to fix all of the sections even more strongly. In the assembly method of an embodiment, the mesh sheet is pasted so as to cover the base and the portions of the sections that are connected to the base, and then the sealant is applied thereon so as to fix the connections, whereby the fixing is done even more firmly. In the assembly method of an embodiment, the clayey paint made of natural substances is applied over the sealant on the upper part of the interior faces of the structure, and an exterior paint is applied over the sealant on the lower part the interior faces of the structure, resulting in graffiti-proof interior faces, especially the lower part of the interior faces. The assembly method of an embodiment uses, as the exterior paint, a modified silicone-plastic paint, which has the advantages of being water repellent and able to screen out ultraviolet light -- at low cost. Because this paint is water-repellant, the exterior of the structure rarely cracks due to rain or snow. The assembly method of an embodiment uses diatomite or a whitewash as the clayey paint. Diatomite removes moisture (because of which condensation is prevented), and adsorbs volatile formaldehyde, and it has excellent sound-insulation and deodorization capabilities. Using a whitewash as the clayey paint suppresses the growth of mold because of whitewash's strong alkalinity, and the whitewash also absorbs and decomposes formaldehyde, which is an acidic gas. The knockdown structure described may have the same advantages as those described in the method above. The knockdown structure described in one embodiment incorporates an aircirculation means and an air-cleaning means inside the knockdown structure, making the structure more comfortable for human living. The knockdown structure described in an embodiment includes an air-circulation means and an air-heating means, which make the structure more comfortable for human living. The knockdown structure described in one embodiment has, as its flooring material, foam polystyrene, which provides under-floor adiathermancy because foam polystyrene is 98% air. Brief Descriptions of the Drawings Fig. 1 is a front view of the dome-shaped knockdown structure in one embodiment. Fig. 2 is a plan view of the knockdown structure. Fig. 3 is an exploded perspective view showing how the knockdown structure is assembled. Fig. 4 is a perspective view showing how the sections are joined together. Fig. 5 is a perspective view showing the junctions on which the mesh sheets are pasted. Fig. 6 is a perspective view of the whole structure on which mesh sheets are pasted. Fig. 7 is a partial cross-section view of a section of the structure's body. Fig. 8 is a partial cross-section view of a section of the structure's body in another embodiment. Fig. 9 consists of partial cross-section views of two different types of junction structures of the sections in another embodiment. Fig. 10 is a perspective view of a section in another embodiment. Fig 11 is a cross-section view of a first example of an embodiment in which a flooring material 23, an air-circulation means, and multiple air-cleaning means are incorporated on the floor. Fig 12 is an exploded perspective view of a second example of the embodiment, in which a flooring material 23, air-circulation means, and two air-cleaning means are incorporated on the floor. Fig. 13 is a plan view showing the arrangement of under-floor pipes in the embodiment shown in Fig. 12. Fig. 14 is a horizontal cross-section view that shows, among other parts, an under-floor pipe in the embodiment shown in Fig. 12. Fig. 15 shows the arrangement of the under-floor pipes in a third example of the embodiment, in which a flooring material 23, air-circulation means, and air-cleaning means are incorporated on the floor. Fig. 16 is a cross-section view of a part of the structure's body, including the mesh sheet used at the junction between the base and a section. Fig. 17 is a perspective view-- from the exterior side of the structure -- that shows a mesh sheet at the junction between the base and a section. 2588743_1 (GHMatter ) Fig. 18 is a cross-section view -- from the interior side of the structure -- that shows mesh sheet at the junction between the base and a section. Fig. 19 is a cross-section view that shows a mesh sheet at the junction between the support material, which is disposed on the base, and a section. Fig. 20 is a perspective view of a variety of embodiments of the knockdown structure. Explanation of the Numbers Used in the Drawings 1 knockdown structure 2 structure's body 3 base 3a supporting face 3b engagement shoulder 4 section 4a engagement piece 4b notched portion 4c end face of section 4f foot of section block 6 coupler plate 7 bolt 8 coupling part junction (between sections) 11, 11 a, 1 l b, 11 c mesh sheet 13 sealant (interior of structure) 14 sealant (exterior of structure) modified silicone-plastic paint (exterior of structure) 17 modified silicone-plastic paint (interior of structure) 18 diatomite 21 concave-convex portion 21a convex portion 21b concave portion 22 wiring groove 23 flooring material 23a concave portion 23b connecting groove 23c convex portion 24 floor panel 24a ventilation hole air-cleaning device 26 pipe 27 ventilation fan 28 support material 29 pipe 33 side-wall section 34 roof section carpet 61 fan 62 heater 100-900 examples of assembled knockdown structures Preferable Embodiment of the Invention An embodiment of the present invention will now be described. Figs. 1 to 6 show a dome-shaped knockdown structure in one embodiment. In this embodiment the knockdown structure 1 has a domed-shaped body 2 as shown in Figs. 1 to 3, and is assembled by standing the structure's body 2 on a base 3. The structure's body 2 is assembled by joining a plurality of sections 4 so as to form a circle. More specifically, the sections 4 form the structure's body 2 by joining the end faces of right and left sides of a section with those of neighboring sections. The sections 4 have the shape that results by dividing a dome shape into a plurality of parts forming a radial pattern around the central axis of the dome-shaped structure's body 2. In this case, it is preferable to divide the dome shape into sections 4 of equal size around the central axis. In this embodiment, all of the sections 4 are the same size, resulting in advantages of easy assembly and the capability of using one metal mold for foammolding all the sections. Each section 4 is made of foam polystyrene and therefore is lightweight and easy to handle, resulting in easy assembly of the structure's body 2. In this case, the thickness of the section 4 and the foaming scale factor of foam polystyrene are properly chosen according to the environment in which the knockdown structure is used. For instance, in an environment requiring adiathermancy and strength, the foaming scale factor should be small and the sections 4 should be thick, while in a different environment the foaming scale factor could be larger and the thickness of the sections 4 could be less. Each section 4 stands on the base 3 by engaging the lower end of the section 4 with the base 3. The base 3 is formed of a plurality of blocks 5 that are arranged in an arc made by equally dividing a circle. From a top viewpoint, the base 3 has the shape of a ring due to the plurality of blocks 5 that are joined together so as to form a circle. The blocks 5 are made of concrete or of stainless steel, and are joined together by coupling plates 6 that are made of a corrosion-resistant metal, such as stainless steel, and bolts 7. A ring shaped supporting face 3a, which is to support the lower end face of the section 4, is formed on the base 3. An engagement shoulder 3b, which extends upward and bends outward into an L shape, is formed on the supporting face 3a. The lower end of the section 4 is inserted between the engaging shoulder 3b and the supporting face 3a, by which the section 4 is engaged with the base 3. In addition, an engagement piece 4a is formed integrally at the lower end of the section 4 by bending the lower end of the section 4 inward. The engagement piece 4a is inserted between the engagement shoulder 3b and the supporting face 3a. [0041 ] The upper end of each section 4 has a notched portion 4b. The notched portion 4b is used in forming a joining hole (not shown) at the top of the structure's body 2 when the sections 4 are joined together to assemble the structure's body 2. A coupling part 8 is installed at the joining hole. The upper ends of the sections 4 are inserted into the coupling part 8 so that the sections 4 are engaged with the coupling part 8 in the same manner whereby the lower end of the section 4 engages with the base 3 (by inserting the lower end of the section 4 between the engagement shoulder 3b and the supporting face 3a). In this way, the coupling part 8 has an effect of bundling together the upper ends of the sections 4. It is preferable that the coupling part 8 be a top-side ventilator having a ventilation hole and operating gear (not shown) that makes it possible to open and close the ventilation hole. The procedure for assembling this embodiment of the dome-shaped knockdown structure will now be described, referring to Figs. 4 to 6. When joining the sections 4, which are made of foam polystyrene, the end faces 4c of neighboring sections are opposite each other (see Fig. 4). In this arrangement, the aforementioned mortar-powder mixed adhesive (not shown) is applied on the end faces 4c of the sections 4, and neighboring sections 4 are bonded together by this adhesive. In other words, joints of the structure's body 2 are fixed by the adhesive. In Fig. 4, the number 10 designates a junction (a junction line in this embodiment) between two sections 4 as one of the joints of the structure's body 2. An acrylic resin such as polyacrylic ester or polymethacrylate ester is used as the adhesive. Mortar powder is mixed and dispersed in this acrylic resin, which has a strong ability to bond foam polystyrene with other items, and therefore the mortar powder firmly joins together the sections 4, which are made of foam polystyrene. The mortar-powder mixed acrylic resin used as the adhesive for the sections 4 is strong and has elasticity, and it also excels in earthquake-resistance and crash-resistance properties. Therefore, the joints of the structure's body 2 will not be cracked even by an earthquake, vibrations, or shock. Moreover, this adhesive is water-resistant, and is able for a long period of time to prevent rain from penetrating the joints. Neighboring sections 4 are joined together by inserting the engagement piece 4a that is at the lower end of each section 4, in between the supporting face 3a and the engagement shoulder 3b of the base 3. Fig. 5 shows the dome-shaped structure's body 2 in the process of being assembled by joining together sections 4, with the mesh sheet 11 being pasted onto the joints of the structure's body 2. The adhesive can be a mortar-powder mixed acrylic resin, which is also used for joining together sections 4, as mentioned above. The adhesive is applied in the shape of the mesh sheet 11 that is to be applied thereon, on the corresponding part of the structure's body 2, including the junction. The mesh sheet 11 is then applied on that part of the structure's body 2, after which the adhesive is again applied thinly on the surface of the mesh sheet 11 that has been applied on the structure's body 2. It takes about 24 hours for the adhesive to dry. The mesh sheet 11 is pasted along the junctions 10 -- which are the joints of the structure's body 2 -- of the sections 4, in such a way that the mesh sheet 11 covers the whole lengths of the junctions It is preferable that the mesh sheet 11 be made of an inorganic fiber, such as a carbon fiber, a glass fiber, or a metal fiber. A sheet made of tensional plastic fiber can also be used. It is preferable that the sheet be woven in a mesh. This embodiment uses a mesh sheet that is from 0.3-mm to 1-mm thick and whose mesh count is 6 (i.e., six meshes per inch). A mesh sheet whose mesh count is 12 or more is too fine to work with, and a mesh sheet whose mesh count is less than 6 is too coarse. Thus, the joints of the structure's body 2 (the junctions l0 between sections 4; see Fig. 4) have not only the bonding power of the mortar-powder mixed acrylic resin, but also the strength and toughness of the mesh sheet 11. Both the bonding power of the mortar-powder mixed acrylic resin and the strength and toughness of the mesh sheet 11 serve to firmly join the sections 4 together. In this embodiment, the joining power of the joint 10 is reinforced by pasting the mesh sheet 11 onto the junctions 10 of the sections 4. Because the mesh sheet 11 covers, from above, the concave portions -- where the adhesive is not applied sufficiently -- of the junctions 10 between the sections 4, unevenness of the appearance is eliminated. Because the outer surface is flattened this way, the sealant, the exterior paint, and the interior a clayey paint, which are to be applied onto the structure's body 2, can each be applied with an even thickness. Therefore, the sealant can be solidified uniformly, resulting in no cracks. In addition, as shown in Fig. 6, the mesh sheet 11 can be applied so as to cover the structure's body 2 in its entirety, including the junctions 10 of the sections 4. After the mesh sheet 1 ! is applied, the sealant is applied in a predetermined thickness on the exterior and interior faces of the knockdown structure's body 2. Plastic paint into which a dispersing fiber (such as a glass fiber or a carbon fiber) and mortar powder are dispersed, is used as the sealant. The plastic paint can be an acrylic resin (such as polymethacrylate ester or polyacrylic ester) or another resin. The sealant should be from 1-cm to 3-cm thick. A sealant like this is thinner than a conventional one. In Fig. 7, the number 13 refers to the sealant that is applied on the interior of the structure's body 2 (section 4), and the number 14 refers to the sealant that is applied on the exterior of the structure's body 2. By using the above-mentioned composition as the sealants 13 and 14, the joints of the sections 4 are maintained firmly. Moreover, because the sealants contain fiber, cracking rarely occurs after the sealants are applied on the structure's body 2. Further, the sealants contain mortar powder, and thus a hard and tough film results. Therefore, even if the inner sections 4 (made of foam polystyrene) vibrate, the vibration is not transmitted outward. [0051 ] After the sealants 13 and 14 are applied, an exterior paint is applied on the surface of the sealant 14 of the exterior faces of the structure's body 2, and the paint for the interior is applied on the surface of the sealant 13 of the interior faces of the structure's body 2. Paint that is water-repellent and that can screen out ultraviolet light is used as the exterior paint. For a paint having such properties, a modified silicon-plastic paint or another plastic paint can be used. In Fig. 7, the number 15 refers to a modified siliconplastic paint that is applied over the sealant 14 on the exterior face of the structure's body 2. The modified silicon-plastic paint 15 contains silicon particles, and therefore it is highly water-repellant and can repel rain and snow. In addition, the modified siliconplastic paint 15 has a strong ability to bond with the sealant 14, and so the paint never comes off. Therefore, even if the dome-shaped structure 1 is assembled outdoors, it has high durability and therefore can be used for a long period of time. In addition, because the modified silicon-plastic paint 15 can screen out ultraviolet light, its application on the exterior face of the structure's body 2 prevents ultraviolet light from penetrating through the modified silicon-plastic paint 15 to the sections 4, which helps to prevent the sections 4 from degrading. Further, because the modified silicon-plastic paint 15 has low surface tension, it rarely gets smudged. Therefore, cleaning the exterior face of the structure's body 2 is easy, so that maintenance is easy. For the modified silicon-plastic paint having the abovementioned properties, an alkyd modified-silicon paint or the like is used. For the modified silicon-plastic paint that is used to paint the exterior of the structure's body 2, a paint made from a pigment such as white titanium pigment or mica can be mixed, so that coloring the exterior face of the structure's body 2 is easy. For the paint that is applied over the sealant 13 of the interior faces of the structure's body 2, a clayey paint made of natural substances is used. Diatomite or a whitewash can be used for the clayey paint made of natural substances. In Fig. 7, the number 18 refers to diatomite as the clayey paint made of natural substances. This diatomite 18 is used for the upper part of the interior faces of the structure's body 2. In this case, the lower part of the interior faces of the structure's body 2 is covered with the same exterior paint as that used for the exterior faces of the structure's body 2, as described above. The number 17 refers to the modified silicon-plastic paint as the exterior paint that is applied on the lower part of the interior faces of the structure's body. Applying the modified silicon-plastic paint 17 on the lower part of the structure's body 2 can give the above mentioned properties to the lower part of the structure's body 2. Because the modified silicon-plastic paint 17 is applied on the lower part of the interior faces of the structure, the surface tension of the lower part is low, and so graffiti is difficult to attach on the lower part. And when that occurs, it is easy to wipe off the graffiti. Therefore, cleaning the knockdown structure 1, when used as a leisure facility, is easy. The main ingredient of the diatomite 18 that is applied on the upper part of the interior faces of the structure's body 2 is phytoplanktons, which are algae. The primary ingredient of diatomite 18 is silicon dioxide, and the diatomite 18 is clayey. Diatomite 18, which mainly consists of silicon dioxide, is heat-resistant, and so even if a lit cigarette or other object that is on fire touches it, it does not easily bum and is safe from fire. Moreover, the diatomite 18 adsorbs and removes formaldehyde, and so it prevents formaldehyde -- which can be emitted by the sealant 13 and the modified silicon-plastic paint 17 -- from remaining inside the structure. Further, diatomite 18 adsorbs and removes poisonous materials, thereby contributing to safety, and it has deodorizing capability and the ability to prevent ticks and mold from growing. Therefore, the dome-shaped structure does not adverse affect the health of a user or the structure's suitability for human living. In this embodiment, a whitewash c m be used instead of diatomite 18 as the clayey paint made of natural substances to be applied on the upper part of the interior faces of the structure's body 2. The primary ingredient of whitewash is calcium hydroxide from soil. Mixing the whitewash with hemp, marine algae and the like causes it to becomes clayey. Whitewash has the same effect of adsorbing and removing formaldehyde as diatomite 18 does, thereby preventing the adverse health effects that can result from formaldehyde. In addition, the whitewash can be applied again, and therefore if smudge that is hard to remove sticks to the surface, the condition can easily be remedied by simply applying a new coat of whitewash. Whitewash is also fire-resistant and does not combust easily. In this embodiment of the dome-shaped knockdown structure 1, the sections 4 can be joined together firmly, surely preventing unintentional disassembly after assembly. Further, metal reinforcing members are not needed to increase the strength of the knockdown structure 1. This makes it easy to assemble the knockdown structure 1 and to simplify the structure of the knockdown structure 1, i.e., the structure's body 2. Fig. 8 shows a cross-section of a section 4 of another embodiment. In this embodiment, as in the first embodiment, a mesh sheet mixed with inorganic fiber is glued along the junction lines between the sections 4, which are made of foam polystyrene and that compose the structure's body 2. On the exterior and interior faces of the structure's body 2, sealants 13 and 14 -- which are made by dispersing resin and mortar powder in a plastic paint such as acrylic resin and the like -- are applied. Further, the modified silicon-plastic paint 15 is applied over the sealant 14 of the exterior faces of the structure's body 2 as an exterior paint that has the ability to repel water and to screen out ultraviolet light. In the embodiment shown in Fig. 8, diatomite 18 -- as the clayey paint made of natural substances -- is applied on the interior faces of the structure's body 2. The diatomite 18 is applied on the entirety of all of the interior faces of the structure's body 2 so that it is not necessary to paint the upper and lower parts of the interior faces differently, as is done in the embodiment shown in Fig. 7. Moreover, because the diatomite 18 is applied on the entirety of all of the interior faces of the structure's body 2, it adsorbs and removes formaldehyde and poisonous materials, and prevents ticks and mold from growing on the interior faces. Also, in this embodiment a whitewash, instead of diatomite 18, can be applied on the entirety of all the interior faces of the structure's body 2. Fig. 9 shows two forms of the junctions between sections 4. In Fig. 9a, stepwise concave-convex portions 21 are formed at opposite side-faces of the sections 4 so as to engage with each other. In Fig. 9b, convex and concave portions 21a, 21 b are formed at opposite side-faces of sections 4 so as to engage with each other. Plastic paint mixed with inorganic fiber and mortar powder is applied between the opposite side-faces so as to join the sections 4 together. With this structure of mutual engagement, the sections 4 can be bound together very firmly. Therefore, the sections 4 can be joined strongly. The shape of the side-faces of a section 4 is not limited to the forms shown in the figures, and the shape can be modified in various ways. In the arrangement shown in Fig. 9, the mesh sheet 11 described earlier (not shown) can be applied so as to cover the junctions between sections 4, enabling the sections 4 to be very firmly joined together. Fig. 10 shows another form of the section 4. In this form, a wiring groove 22 for electric cords and the like is formed on the interior face of the section. The wiring groove 22 is made by moving an electric iron or the like on the interior face of the section 4. The wiring groove 22 can be formed easily because the section 4 is made of foam polystyrene. Electric cords, LAN cables for a personal computer, and other wires or cables can be put in the wiring groove 22, and the wiring groove 22 is sealed by the exterior paint described above, by a clayey paint, or by a dedicated mounting material. With this wiring groove 22, a power supply and signal-transmission capability can be provided for electric lights, a refrigerator, a television, a personal computer, and/or other electric equipment, thereby improving the usefulness of the knockdown structure 1. Grooves 22 can also be formed on the exterior face of a section 4. A flooring material made of foam polystyrene can be provided for the floor of the structure's body 2. Using foam polystyrene as the flooring material makes the floor adiathermic -- as with the walls, which are formed of sections 4 and are adiathermic -- and therefore livability is improved. Fig 11 is a cross-section view of a first example of an embodiment in which a flooring material 23, an air-circulation means, and an air-cleaning means are incorporated on or in the floor."> The flooring material 23 is allocated on the floor of the structure's body 2, which is comprised of sections 4. This flooring material 23 can be formed by joining together sections made of foam polystyrene, using an adhesive. A flooring panel 24, which is made of resin, is laid on the flooring material 23. Next, as shown in Fig. 11, the air-circulation means comprises concave portions 23a that are arranged at proper intervals on the upper surface of the flooring material 23; connecting grooves 23b that link neighboring concave portions 23a; ventilation holes 24 in the flooring panel 24; pipes 26 that are installed in the side walls; and a ventilation fan 27. In each concave portion 23a, an air-cleaning device 25, which is made of bamboo carbon, activated carbon, or the like. Accordingly, air inside the structure's body 2 is moved into and through the section 4 via the fan 27, returning to the inside of the structure per se through ventilation holes 24a after dust and odor have been removed by the air-cleaning device 25. Thereby the air inside the structure's body 2 can be cleaned, further improving the livability of the knockdown structure. Fig 12 is an exploded perspective view of a second example of the embodiment, in which a flooring material, an air-circulation means, and an air-cleaning means are incorporated in the floor. In the example shown in Fig. 12, the under-floor pipe 29 is used for the under-floor portion of the airflow path. The configuration of the remaining parts -- the flooring panel 24, ventilation holes 24a, a flooring material 23 made of foam polystyrene, convex portions 23c, an air-cleaning device 25 -- is the same as that shown in Fig. 11. Also, the carpet 60 is made of an air-permeable material. Fig. 13 is a plan view showing the layout of the under-floor pipe 29 in the embodiment shown in Fig. 12. The under-floor pipes 29 are arranged in such a way that one end of each pipe is connected with the side wall of the structure's body 2 and the other end of the pipe faces the central part of the structure. The under-floor pipes 29 could instead be arranged radially. For this example, a total of 12 under-floor pipes are used. Thus, cleaned air rises upwards in the structure through the ventilation holes 24a that are located throughout the flooring panel 24. The steams of upward-rising air from all portions of the structure's body 2 meet together in the upper part of the structure 1 and then circulate within the structure 1. Fig. 14 is a horizontal cross-section of the under-floor pipe 29. As shown in Fig. 14, a fan 61 and a heater 62 are provided inside the under-floor pipe 29 so as to heat and circulate air. Fig. 15 is a layout drawing showing the arrangement of the under-floor pipes of a third example of the embodiment, in which a flooring material is provided on the floor, and an air-circulation means and an air-cleaning means are incorporated in the floor. This third example, unlike the embodiment depicted in Fig. 11, does not include pipes 26 in the side wall of the section 4, or a ventilation fan 27. The openings at the two ends of the under-floor pipe 29 (indicated by arrows in solid lines) becomes either an exhaust or an inhale nozzle, depending on the rotational direction of the fan in the under-floor pipe 29. Figs. 16 to 18 shows another embodiment for using the mesh sheet. The mesh sheet 11 is applied on the junctions 10 between adjacent sections 4. The mesh sheet 11 is also applied along the junction between each section 4 and the base 3, as shown in Fig. 16, in which the numbers 1 la and 11 b refer to the mesh sheet. The mesh sheets l l a and ] 1 b are applied on the outer and inner peripheries, respectively, of the structure's body 2, as shown in Figs. 16 to 18. The mesh sheet 1 la is applied on the lower end of the exterior face of the sections 4 of the structure's body 2 and the corresponding part of the base 3, as shown in Fig. 17. The mesh sheet 1 la covers the outer periphery of the lower end of the structure's body 2, and is applied seamlessly over the lower end of the sections 4 and over the base 3. Likewise for the interior faces of the structure's body 2, the mesh sheet 1 lb is applied seamlessly over the lower end of the section 4 and the base 3, as shown in Fig. 18. At the lower end of the inner face of the sections 4, a foot 4f that extends towards the interior of the structure is formed, and the mesh sheet 1 lb is applied over the foot 4fand the corresponding part of the base 3. For the interior and exterior faces of the structure's body 2, sealants 13 and 14 are applied so as to cover the mesh sheets 11, 1 la, and 1 lb, so as to prevent the appearance from deteriorating. The mesh sheets 1 la and 1 lb, in addition to being applied on the junctions l0 between sections 4, are applied on the portion of each section 4 that connects with the base 3, as well as with the corresponding part of the base 3. Thus, the strength of the bonding of the sections 4 to the base 3 is increased, which enables the structure's body 2 to stand steadily on the base 3. Fig. 19 is a cross-section view showing that mesh sheets are pasted on the junction of the support material and the section 4, both of which are arranged on the base 3. In this embodiment, the support material 28, made of foam polystyrene, is fixed onto the base 3, which is made of concrete. The support material 28 constitutes a part of the base 3. A plurality of sections 4 are arranged in a standing condition on the support material 28. The mesh sheets 1 la and 1 lb are applied on the part of each section 4 that rises from the support material 28, and on the corresponding part of the support material 28. The mesh sheet 1 la is applied on the lower part of the exterior faces of the sections 4 of the structure's body 2, and the mesh sheet 1 lb is applied on the lower part of the interior face of the sections 4. In the embodiment shown in Fig. 19, the flooring material 23 is laid on the support material 28, which is on the base 3, and the mesh sheet 1 lc is applied over a boundary part between this flooring material 23 and each of the sections 4. The mesh sheet 1 lc is applied so as to cover the comer part of the structure's body 2, which is the boundary part between the section 4 and the flooring material 23. More specifically, the mesh sheet 1 lc is seamlessly applied on the comers of the interior faces of the section 4 of the structure's body 2. Thus, the strength of the bonding between each of the sections 4 and the flooring material 23 is increased, enabling the structure's body 2 and the flooring material 23 to be joined together under a very stable condition. Fig. 20 is a perspective view of a variety of shapes of knockdown structures. They are: 100, a domed-type; 200 to 400, long domed-types; 500, a domed-type that has one 90-degree-vertical side and one inward-slanting vertical end; 600, a domed-type that has one 90-degree vertical end; 700, a domed-type that has two 90-degree-vertical ends; 258B743_1 (GHMatters) 800, a domed-type that has one 90-degree-vertical end and one inward-slanting vertical end; and 900, a domed-type that has two inward-slanting vertical ends. These models have side walls and roofs. The side walls are assembled by joining sidewalls of neighboring sections 33, and the roofs are formed by joining roofs of neighboring sections 34. The side-wall sections 33 and 34 are made of foam polystyrene, and the mesh sheet 11 described above is used to join the sections together. Thus, the bonding strength between the sections is improved, enabling the knockdown structure to have a stable structure. Industrial Applicability The knockdown structures and the assembly methods thereof described in the present invention are suitable for outdoor facilities used as accommodation facilities, leisure facilities, and facilities used for other purposes. In the claims which follow and in the preceding description of the invention, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention. It is to be understood that, if any prior art publication is referred to herein, such reference does not constitute an admission that the publication forms a part of the common general knowledge in the art, in Australia or any other country.