Snow-resistant roof structure

Abstract

To provide a double-layered snow-resistant roof structure that can withstand snow loads. [Solution] The snow-resistant roof structure 1 is a double-layered structure in which a heat-shielding steel plate 4 is provided on the outdoor side of an existing roofing material 2 having a recess 2A and a protrusion 2B, with a steel plate 5 on which a material 3 with high reflectivity to radiant heat, such as aluminum foil, is attached to the inside. In this snow-resistant roof structure 1, multiple support members 6 with a Z-shaped cross-section or support members 10 with an inverted V-shaped cross-section that widens from top to bottom are attached along the roof flow direction X of the recess 2A of the existing roofing material 2, and the contact parts between the heat-shielding steel plate 4 and the support members 6 and 10 are fixed and rigid with double-sided tape 7 or screws.

Description

[Technical Field]

[0001] This invention provides a double-layered, thin, snow-resistant heat-shielding steel plate structure that can withstand snow loads and is lightweight, making it usable even in heavy snowfall areas. This structure improves the indoor environment by allowing ventilation in the summer and enhances heating efficiency by creating still air in the winter. [Background technology]

[0002] For energy-saving purposes, roofing materials with insulation material between two layers of steel roofing sheets are used (for example, Patent Document 1). Flat heat-shielding steel sheet structures with heat-shielding material installed on the inside are used on top of standing seam corrugated sheet roofing materials (for example, Patent Document 2). [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2026-6688 [Patent Document 2] Japanese Patent Publication No. 2022-45526 [Overview of the project] [Problems that the invention aims to solve]

[0004] Currently, for energy-saving purposes, roofing materials with insulation placed between two layers of steel roofing sheets are being used. This construction method involves placing insulation material such as glass wool between two layers of corrugated metal roofing sheets of the same shape. Insulation has a large heat storage effect and is very effective for heating in winter. However, in summer, this heat storage effect has the opposite effect, and it produces almost no cooling effect. In addition, although it is necessary to make the roof a two-layer structure, it is necessary to use roofing materials of the same shape to create a space, so the weight of the roofing material increases, and as a result the roof itself becomes heavy, which often causes problems with seismic performance. Moreover, in heavy snowfall areas, the added load of snow makes the situation even more severe.

[0005] A flat, heat-shielding steel plate structure is used, with a heat-shielding material installed on the inside, on top of the folded-seam roofing material. This structure involves creating a new roof by dropping a thin, flat sheet of heat-shielding steel onto the existing folded metal roofing material. The sheet has a high reflectivity against radiant heat, such as aluminum foil, on the inside. This sheet is bent so that one end wraps around the entire seam, and the other end rests on the seam. The new roof is then installed by dropping the sheet from the outside of the existing roofing material onto the existing folded metal roofing material.

[0006] This construction method minimizes seismic resistance issues while improving the indoor environment and saving energy. To achieve this, the new roofing steel sheets are only 0.27mm thick, significantly thinner than the 0.5mm to 0.8mm thickness of commonly used double-layered roofs. The new roofing material is secured only by screws on the sides of the seams, but it is still usable without problems against wind. However, it cannot withstand the actual load of snow (300 kg / m³) from heavy snowfall areas, which is applied vertically. 2 It is considered difficult to address this.

[0007] This invention was made to solve these problems and aims to provide a double-layered snow-resistant roof structure that can withstand snow loads. [Means for solving the problem]

[0008] The snow-resistant roof structure according to the present invention is a double-layered structure in which a heat-shielding steel plate, with a material that has a high reflectivity against radiant heat, such as aluminum foil, attached to the inside of the steel plate, is provided on the outdoor side of the existing roofing material which has recesses and protrusions. Multiple support members with a Z-shaped cross-section or an inverted V-shaped cross-section that widens from top to bottom are attached along the roof slope direction of the recesses of the existing roofing material, and the contact portions between the heat-shielding steel plate and the support members are fixed and rigid with double-sided tape or screws.

[0009] The snow-resistant roof structure according to the present invention is characterized in that a Z-shaped support member or an inverted V-shaped support member has multiple perforations formed therein, and the weight of the Z-shaped support member or the inverted V-shaped support member is reduced by forming these perforations.

[0010] The snow-resistant roof structure according to the present invention is characterized in that a ventilation layer is formed between a material with high reflectivity to radiant heat, such as aluminum foil, and the existing roofing material, and an opening and closing device is provided on the ridge, which is made of heat-shielding steel plate, which opens and closes in response to the temperature of the outside air, and the amount of ventilation in the ventilation layer is adjusted by opening and closing the opening and closing device. [Effects of the Invention]

[0011] The snow-resistant roof structure according to the present invention has multiple support members with a Z-shaped or inverted V-shaped cross-section when viewed from the direction of the roof flow attached approximately in the center of the recess of the existing roofing material and along the direction of the roof flow. Therefore, it can withstand loads placed on the heat-shielding steel plate due to snow accumulation, etc. Since a thin heat-shielding steel plate is used, the load on the building can be reduced by using a thin heat-shielding steel plate, and the seismic performance of the building constructed with the snow-resistant roof structure can be improved.

[0012] Furthermore, in the snow-resistant roof structure according to the present invention, an opening and closing device is provided on the ridge, which is made of heat-shielding steel plate, that opens and closes in response to the temperature of the outside air. The opening and closing of the opening and closing device adjusts the amount of air ventilated in the ventilation layer. For example, when the temperature drops below 18°C, the opening and closing device closes completely, forming a layer of still air in the ventilation layer, which significantly improves the heat retention effect of the building. Therefore, by constructing a snow-resistant roof structure on a building, significant energy savings can be achieved. [Brief explanation of the drawing]

[0013] [Figure 1] This figure shows a heat-shielding steel plate constituting a snow-resistant roof structure according to an embodiment of the present invention, where (a) is a perspective view and (b) is a front view. [Figure 2] This figure shows a snow-resistant roof structure according to an embodiment of the present invention, where (a) is a left side view of a Z-shaped support member, and (b) is a cross-sectional view of a snow-resistant roof structure using a Z-shaped support member constructed on an existing roofing material, a standing seam corrugated metal roof. [Figure 3] This is a cross-sectional view of a snow-resistant roof structure according to an embodiment of the present invention, in which an inverted V-shaped support member is used. [Figure 4] It is a cross-sectional view of a snow-resistant roof structure when a snow-resistant roof structure according to an embodiment of the present invention is constructed on a goze-type folded plate roof which is an existing roofing material, and a face door is provided at an air intake port. [Figure 5] It is a schematic diagram in which an opening / closing device is provided on a ridge formed of a heat-shielding steel plate in the snow-resistant roof structure according to an embodiment of the present invention. Description of Embodiments

[0014] The best mode for carrying out the present invention will be described with reference to FIGS. 1 to 5.

[0015] Nowadays, as air temperatures have come to exceed body temperature, countermeasures against summer heat are extremely important. In order to block radiant heat, which is the largest factor of heat entering buildings, there is a construction method of arranging a material with high reflectivity to radiant heat such as aluminum foil inside and outside a building. However, when the air temperature exceeds body temperature, it must be considered that there are two heat sources: one on the outdoor side and one on the indoor side. Therefore, simply installing a single layer of a material with high reflectivity to radiant heat such as aluminum foil is insufficient for future countermeasures against high temperatures, and a construction method that simultaneously discharges both heat entering from the outdoors and heat generated from inside the room has become important.

[0016] In order to deal with this, a construction method in which the exterior material of a building has a double structure, a material with high reflectivity to radiant heat such as aluminum foil is applied on the indoor side of the outer exterior material, and ventilation is further provided on the indoor side which is the radiation side thereof is effective, and achieves 60% energy saving.

[0017] However, heretofore, for a double structure of uneven roofing materials, a common construction method is to use a new roofing material having roughly the same shape as the existing roof shape, which makes the roof load nearly double, and the problem of earthquake resistance has been a concern. Accordingly, a construction method using a flat thin steel plate has been developed, which reduces the weight of the new roof by about 60% compared to the conventional one, and has made it possible to greatly improve earthquake resistance.

[0018] However, in snowy regions, the snow accumulation amount is 200Kg / m 2 , and in heavy snowfall areas it is 300Kg / m 2With the requirement to withstand snow loads, earthquake resistance once again becomes a major issue. In other words, in heavy snowfall areas, it is extremely important to have a lightweight yet strong building structure that is not only cool in summer and warm in winter, saving energy, but also able to withstand earthquakes and snow.

[0019] As shown in Figures 1 and 2, the snow-resistant roof structure 1 according to the present invention is a double-layered structure in which a thin, flat heat-shielding steel plate 4 is provided on the outdoor side of an existing roofing material 2 having a recess 2A and a protrusion 2B, with a material 3 that has high reflectivity to radiant heat, such as aluminum foil, attached to the inside. The heat-shielding steel plate 4 is a flat steel plate 5 with the material 3 that has high reflectivity to radiant heat, such as aluminum foil, attached to it. In this snow-resistant roof structure 1, a plurality of support members (reinforcement members) 6, which have a Z-shaped cross-section when viewed from the direction of flow X, are attached approximately in the center of the recess 2A of the existing roofing material 2 and along the direction of roof flow X, and the contact portion between the heat-shielding steel plate 4 and the support members 6 is fixed with double-sided tape 7 to make it rigid. A ventilation layer 8 is formed between the material 3 that has high reflectivity to radiant heat, such as aluminum foil, and the recess 2A of the existing roofing material 2. The contact portion between the heat-shielding steel plate 4 and the support members 6 may be fixed with screws. Alternatively, instead of the Z-shaped support member 6, an inverted V-shaped support member (reinforcement member) 10 that widens from top to bottom can be used, as shown in Figure 3.

[0020] The present invention is a double-layered exterior structure in which a heat-shielding steel plate 4 is attached to an existing roofing material 2 having a recess 2A and a protrusion 2B. Generally, the thickness of the new steel plate in a double-layered roof is about 0.5 mm to 0.8 mm, but the steel plate 5 used in the present invention is extremely thin at 0.27 mm. Furthermore, the steel plate 5 used in the present invention has a generally flat shape, unlike the uneven shape of commonly used double-layered structures, and is approximately 60% lighter. However, because this thin steel plate 5 (heat-shielding steel plate 4) is used on a flat surface, it is very susceptible to vertical loads such as snow. Therefore, in order to reinforce this flat steel plate (heat-shielding steel plate 4), the snow-resistant roof structure 1 of the present invention has a structure in which a Z-shaped support member 6 or an inverted V-shaped support member 10 for supporting the heat-shielding steel plate 4 is provided near the center of the recess 2A of the existing roofing material 2 and in the direction of roof flow X.

[0021] As will be described later, a ventilation layer 8 is provided on the inside (indoor side) of the heat-shielding steel sheet 4 to dissipate heat entering from the roof. Laminar flow is preferable for this airflow, and minimizing turbulence is crucial. It is also possible to install the heat-shielding steel sheet 4 in a direction perpendicular to the roof flow direction X of the existing roofing material 2, but this would make turbulence more likely to occur, thus preventing improvements in the indoor environment and significant energy savings.

[0022] The steel plate 5 is made of galvalume steel (registered trademark) to ensure a 30-year lifespan. While thin steel plates typically have a thickness of approximately 0.27 mm to 0.35 mm, the snow-resistant roof structure 1 of this invention uses a steel plate 5 with a thickness of 0.27 mm.

[0023] The steel plate has a fitting portion 5A formed on one end and a contact portion 5B formed on the other end. Specifically, the shape of the steel plate 5 is based on a folded metal roofing material with seams, so one end of the heat-shielding steel plate 4 is U-shaped to wrap around the seam, and the other end is shaped to rest on the top of the adjacent seam (Figure 1). Therefore, a new roof can be constructed simply by dropping this heat-shielding steel plate 4 from the outside of the existing roofing material 2. The length of the heat-shielding steel plate 4 is about 3 to 4 m, and each weighs 4 kg to 6 kg, making it easy to carry.

[0024] The Z-shaped support member 6 is constructed by bending a galvalume steel sheet (registered trademark) with a thickness of 0.27 mm to 0.50 mm into a Z-shape. The Z-shaped support member 6 has an upper edge portion 6A, a lower edge portion 6B, and a side edge portion 6C that connects the upper edge portion 6A and the lower edge portion 6B (Figure 2). The upper edge portion 6A is fixed to the material 3 of the heat-shielding steel sheet 4, such as aluminum foil, which has a high reflectivity against radiant heat, by double-sided tape 7, and the lower edge portion 6B is fixed to the recess 2A by double-sided tape 7. In most cases, a Z-shaped support member 6 can be used, but if greater strength is desired, an inverted V-shaped support member 10 can be used. This inverted V-shaped support member 10 has an upper side portion 10A, two side portions 10C extending downward from the upper side portion 10A, and a lower side portion 10B connected to the side portions 10C.

[0025] The snow-resistant roof structure 1 of the present invention uses special double-sided tape 7 to reinforce the structure made of thin steel plates. In areas with relatively little snowfall, it is applied to two locations, upper and lower, of the support member 6: the contact point between the new heat-shielding steel plate 4 and the support member 6, and the contact point between the support member 6 and the recess 2A of the existing roofing material 2. In heavy snowfall areas, it is also applied to the protrusion 2B of the existing roofing material 2, and to the contact point between the side of the seam and the heat-shielding steel plate 4, so each existing roofing material 2 has two points of application on both sides. In other words, in heavy snowfall areas, the entire cross-section is made rigid by bonding a total of four locations with the special double-sided tape. This special double-sided tape can adhere even when the surface of the steel plate 5 is slightly wet. Furthermore, its adhesive strength to metal is very strong, making it possible to reliably form a rigid body.

[0026] The screws are typically driven into the heat-shielding steel plates 4 on the sides of the seam at 750mm to 1000mm intervals, but in heavy snowfall areas, the interval is reduced to 500mm to increase strength. Also, in areas with a snow load of 200 kg / m² 2 In areas exceeding this range, it is also possible to screw the existing roofing material 2 at approximately 500mm intervals from the top of the heat-shielding steel plate 4 contact point on the side of the convex 2B seam. Of course, since galvanic corrosion is a concern, we use a specification with a 4mm stainless steel gasket.

[0027] Material 3, such as aluminum foil, which has a high reflectivity to radiant heat, is significantly different from materials used in typical still air conditions. The important point is abrasion and vibration caused by air. To address this, the snow-resistant roof structure of the present invention uses aluminum foil with a thickness of 38 μm to 50 μm. Of course, the strength can be further increased by backing it with PET or polyester material and directly bonding it to the steel plate 5. Although it is not a problem if it is not directly bonded, the aforementioned problems may occur. Furthermore, since ventilation increases the possibility of corrosion due to contact with acid and alkaline components in the atmosphere, a thin film of resin is formed on the surface. As a result, although the reflectivity of the material is approximately 98%, the reflectivity becomes approximately 95% after surface treatment.

[0028] By forming circular or elliptical through-holes 6D and 10D in the side portions 6C of the Z-shaped support member 6 and the side portions 10C of the inverted V-shaped support member 10 used in the snow-resistant roof structure 1 of the present invention, the weight of these support members 6 can also be reduced (Figure 2(a)).

[0029] The steel plates of the Z-shaped support member 6 and the inverted V-shaped support member 10 are thin, so their weight per unit area is not large. However, the length used is the total length of the recess 2A, which is a considerably long distance. Therefore, further weight reduction is important, and this is achieved by forming circular or elliptical through holes 6D and 10D in the side portions 6C and 10C. For example, through holes 6D and 10D with a diameter of 80 mm are drilled in the side portions 6C and 10C of the steel plate at intervals of 100 mm.

[0030] In the snow-resistant roof structure 1 of the present invention, a ventilation layer 8 is formed between a material 3 with high reflectivity to radiant heat, such as aluminum foil, and the existing roofing material 2. Furthermore, as shown in Figure 5, the ridge, which is formed by providing a heat-shielding steel plate 4, is equipped with an opening / closing device 20 that can control the amount of ventilation in the ventilation layer 8 according to the outside air temperature. The opening / closing device 20 is the same type as conventional devices (for example, Japanese Patent Application Publication No. 2025-29733, etc.).

[0031] The snow-resistant roof structure 1 of the present invention utilizes the low radiance properties of a material 3 with high reflectivity to radiant heat, such as aluminum foil, so a ventilation layer 8 is formed on the interior side. Air enters from the eaves and is expelled from the ridge, which is effective in expelling heat in the summer, but has the opposite effect in the winter. Therefore, an opening and closing device 20 is installed on the ridge that detects the outside temperature and controls the amount of air ventilated in the ventilation layer 8. This opening and closing device 20 is a slide-type opening and closing device 20 using a spring-type shape memory alloy, and is fully closed when the temperature is 18℃ and fully open when the temperature is 28℃. In other words, when the outside temperature is high, the amount of air ventilated in the ventilation layer 8 increases, but as the outside temperature decreases, the amount of air ventilated in the ventilation layer 8 decreases, thus controlling the roof temperature 24 hours a day, 365 days a year with zero energy. Of course, when it is cold below 18℃, it is fully closed, so the ventilation layer 8 changes to a still air layer, forming an air insulation layer, and a warm environment is obtained.

[0032] The present invention will now be described in detail. First, an overview of how to carry out the invention will be explained. Even in heavy snowfall areas, temperatures are rising year by year, so in order to significantly change indoor environments and achieve substantial energy savings, it is necessary to address several important issues.

[0033] First, it's necessary to recognize that there are two heat sources affecting humans: one from the outdoors and one from indoors. Until now, indoor temperatures were lower than body temperature, so although it got hot when the sun rose, it was manageable if we could block the heat from outside. However, from now on, indoor temperatures will exceed body temperature. In other words, even when humans are indoors, the surrounding temperature is higher than the human body temperature, and according to the principle that heat moves from a higher temperature to a lower temperature, the surrounding heat will place a considerable burden on humans through radiation and convection. Therefore, unless both of these heat sources are blocked, environmental improvement will not be achieved.

[0034] Secondly, when there are two heat sources, conventional heat-shielding methods using either exterior or interior materials alone are insufficient. The key is to implement a method that simultaneously dissipates heat from both the outside and inside. This method involves utilizing the low radiance properties of heat-shielding materials to minimize heat intrusion into the interior, and then finding a way to expel that small amount of heat. Furthermore, it is preferable to dissipate heat generated from the interior, particularly from the ceiling where the heat output is highest.

[0035] Thirdly, while ventilation is good in the summer, it creates the problem of being cold in the winter. Therefore, a construction method is needed to stop the ventilation layer in winter. In the snow-resistant roof structure 1 of the present invention, an opening and closing device 20 using a shape memory alloy unit is used to allow ventilation through the ventilation layer 8 when it is hot, and to retain heat by keeping it as still air when it is cold.

[0036] Fourth, in order to improve seismic performance, it is necessary to minimize the load on the building. In this invention, by using thin, flat steel plates 5, a construction method is adopted that is approximately 40% to 60% lighter than a typical double-layered roof, and in areas with little snowfall, it is approximately 2.7 kg / m 2 Even in heavy snowfall areas, it weighs approximately 3.2 kg / m². 2 That is the case.

[0037] Fifth, in snowy regions, the average snow depth is 200 kg / m². 2 In heavy snowfall areas, the snow volume is 300 kg / m³. 2 Buildings are required to withstand heavy snow loads, and seismic resistance becomes a major challenge. In other words, in heavy snowfall areas, not only is energy-saving construction that keeps buildings cool in the summer and warm in the winter important, but lightweight and strong building structures that can withstand earthquakes and snow are also extremely important.

[0038] Sixth, given the increasing frequency of natural disasters, it goes without saying that construction methods that use no energy at all are preferable.

[0039] Next, the snow-resistant roof structure 1 according to the present invention will be described. In the present invention, in order to reduce the weight of a new roof, a Galvalume steel sheet (registered trademark) of only 0.27 mm is used in the horizontal direction which requires a minimum area, so the weight can also be minimized. There is no problem as long as the material 3 having high reflectivity to radiant heat such as aluminum foil is disposed between the new roof material (steel sheet 5) and the existing roof material 2. However, in the present invention, the strength of the heat-shielding steel sheet 4 is enhanced by directly adhering the material to the steel sheet 5 of the new roof material.

[0040] The shape of the heat-shielding steel sheet 4 is configured such that one end of the heat-shielding steel sheet 4 is fitted onto an existing seam, and the other end is placed on the top end of the seam. That is, the heat-shielding steel sheet is designed such that a roof can be constructed immediately after it is fitted onto the seam from above the existing roof material 2. The width of the heat-shielding steel sheet 4 corresponds to the seam spacing, and the length is set to be 3 m to 4 m. Therefore, the weight per sheet is about 4.1 Kg for a length of 3 m, about 5.5 Kg for a length of 4 m, and 3 Kg / m 2 or less. With this weight, an operator can easily carry the heat-shielding steel sheet, so workability is also improved.

[0041] However, in this state, the structure cannot withstand snow load. Furthermore, it is necessary to consider a load of 300 Kg / m 2 in heavy snowfall areas. Therefore, a support member 6 formed by bending a steel sheet of about 0.27 mm to 0.5 mm into a Z shape is vertically erected near the center of the concave portion 2A of the existing roof material 2 to support the heat-shielding steel sheet 4 from the lower side. By performing construction at the central portion, the load applied to the heat-shielding steel sheet 4 can be halved compared to conventional cases, and the strength is greatly increased. To further increase the strength, an inverted V-shaped support member 10 may also be used. In addition, in order to further reduce the weight of these support members 6 and 10, when a relatively thick member such as a 0.5 mm steel sheet is used, round or elliptical through holes 6D and 10D can be formed to perform punching.

[0042] In order to increase the strength of these steel members, adhesion is performed at a total of four locations with special double-sided tape 7: the upper side portions 6A, 10A and lower side portions 6B, 10B of the support members 6, 10, and two contact portions between the side of the seam of the convex portion 2B of the existing roof material 2 and the heat-shielding steel sheet 4, so that the whole structure is rigidified. In areas with little snow, double-sided tape is only used on the upper side portions 6A, 10A and lower side portions 6B, 10B of the support members 6, 10.

[0043] As shown in Figures 4 and 5, a flashing 12 is provided at the air intake 11 formed between the existing roofing material 2 and the heat-shielding steel plate 4 to minimize the exchange of air in winter and cold weather. This flashing 12 is fixed with screws, leaving the lower part of the air intake 11 open. The heat-shielding steel plate 4 is fixed by installing 4mm stainless steel screws with gaskets at 500mm intervals from the side of the seam.

[0044] Finally, let's discuss heat transfer. In the snow-resistant roof structure 1 of the present invention, the low radiance performance of a material 3 with high reflectivity to radiant heat, such as aluminum foil, the ventilation layer 8, and the opening / closing device 20 utilizing a shape memory alloy unit can be used to improve the indoor environment and achieve significant energy savings. Approximately 10% of the heat from the outside is reflected by the surface of the heat-shielding steel plate 4, but the remainder moves to the inside in the form of conductive heat. However, since a material 3 with high reflectivity to radiant heat, such as aluminum foil, is applied to the indoor side of the steel plate 5, conductive heat is blocked here and returned to the outside in the form of conductive heat, and radiated into the atmosphere. Therefore, only a very small amount of radiant heat is transferred to the inside. For example, if a material 3 with high reflectivity to radiant heat, such as aluminum foil with a reflectivity of 95%, is used, only about 5% is transferred into the ventilation layer 8. This heat is ultimately transferred to the air in the ventilation layer 8 and discharged to the outside in the form of convective heat. At this time, the support members 6 and 10 of the heat-shielding steel plate 4 are installed parallel to the airflow, and since convective heat flows along the underside of the heat-shielding steel plate 4, turbulence is unlikely to occur, and an ideal ventilation layer 8 is formed, resulting in minimal heat loss.

[0045] On the other hand, while the temperature near the ceiling can reach 60 to 70°C in the summer, the air flowing through the ventilation layer 8 is at ambient temperature, approximately 40°C. This heat from the room is then transferred to the air in the ventilation layer 8 and expelled, significantly lowering the ceiling temperature. Most of the materials used in the room have high emissivity, so a decrease in this temperature means a dramatic reduction in radiation, making it possible to dramatically improve the indoor environment. However, while this is good in the summer or when the temperature is high, ventilation in winter or when it is cold will actually lower the room temperature.

[0046] This is where the opening and closing device 20, which uses a shape memory alloy unit installed on the roof, comes into play. This opening and closing device 20 closes completely when the outside temperature is 18°C ​​and opens completely when the outside temperature is 28°C. A shape memory alloy spring detects the outside temperature and contracts, opening and closing the sliding opening and closing device. As a result, it can operate 24 hours a day, 365 days a year with zero energy consumption. In winter in heavy snowfall areas, the temperature is almost always below 18°C, so the inside of the ventilation layer 8 becomes an air insulation layer, enhancing the heating effect.

[0047] [Test 1] Two parallel rows of 500mm wide, 3m long folded-seam roofing panels were fixed securely to the floor. 0.5mm thick Z-shaped metal fittings (support members) were attached to the center of the inner recesses of the folded roofing panels using double-sided tape on both the top and bottom. Double-sided tape was also applied to the sides of the seams where the heat-shielding steel plates would contact the raised sections of the folded panels. On top of this, a heat-shielding steel plate, as shown in Figure 1, consisting of a 0.27mm thick galvalume steel plate (registered trademark) with a 50μm thick breathable heat-shielding material attached, was installed and secured to the sides of the seams at 50cm intervals using 4mm snow-resistant screws. Two days later, when the adhesive performance of the double-sided tape had stabilized, 20kg sandbags were placed at a rate of 320kg / m². 2 The sample was placed in this manner, and the progress was observed for two weeks.

[0048] [Result 1] (i) There is no distortion in the recessed cross-section of the corrugated metal roofing material or dents in the heat-shielding steel plate, and the Z-shaped support members remain unchanged, with a load capacity of 320 kg / m 2 It was able to withstand the weight. (b) The sandbags also appeared to be almost identical to their installed state in terms of appearance. (h) Attempts were made to remove the sandbags and peel off the heat-shielding steel plates, but they could not be removed at all.

[0049] [Consideration 1] (i) Although sandbags enclosed in plastic bags were used, in the case of snow, they will be in complete contact with the ground, so the load will be more uniform than in this test load, 320 kg / m 2 It is considered to be sufficiently resistant to that. (b) When snow is compressed, the weight of the snow can be borne by the entire corrugated metal roofing material, including the seams, so it is thought that the snow load can withstand a greater weight than when the load is distributed.

[0050] Next, the effects and advantages of the snow-resistant roof structure 1 according to the present invention will be explained.

[0051] In this embodiment, the snow-resistant roof structure 1 has multiple support members 6 attached to the approximate center of the recess 2A of the existing roofing material 2 and along the roof flow direction X, with a cross-section that is Z-shaped when viewed from the flow direction X. The contact portion between the heat-shielding steel plate 4 and the support members 6 is fixed with double-sided tape 7. Furthermore, a thin heat-shielding steel plate 4 is used to form a double-layer structure. Since the heat-shielding steel plate 4 is supported by the Z-shaped support members 6, it can withstand loads applied to the heat-shielding steel plate 4 due to snow accumulation, etc. Furthermore, if an inverted V-shaped support member 10 is used, it can withstand even heavier loads.

[0052] In the snow-resistant roof structure 1 according to this embodiment, by using a thin heat-shielding steel plate 4 and a Z-shaped support member 6 or an inverted V-shaped support member 10, the load on the building can be reduced and seismic performance can be improved.

[0053] In the snow-resistant roof structure 1 according to this embodiment, a ventilation layer 8 is formed, and an opening / closing device 20 that detects the outside temperature and opens and closes is provided at the ridge, which is in communication with the ventilation layer 8. By providing the opening / closing device 20, when the temperature falls below 18°C, it becomes fully closed, and a layer of still air is formed inside the ventilation layer 8. As a result, the heat retention effect of the building is greatly improved, and significant energy savings can be achieved. When a layer of still air is formed, the temperature of the existing roofing material 2 rises, which also has the effect of suppressing condensation inside the room.

[0054] Although this embodiment has been described above, it is possible to select or replace the configurations listed in the above embodiment, or to change them to other configurations as appropriate, as long as they do not deviate from the spirit of the present invention. [Explanation of Symbols]

[0055] 1. Snow-resistant roof structure 2 Existing roofing materials 2A Recess 2B protrusion 3. Materials with high reflectivity against radiant heat, such as aluminum foil. 4 Heat-shielding steel plate 5 steel plate 5A Mating part 5B Contact part 6. Z-shaped support member (reinforcement member) 6A Upper part 6B Lower edge 6C Side part 6D Through hole (perforated section) 7. Double-sided tape 8. Ventilation layer 10. Inverted V-shaped support member (reinforcement member) 10A Upper part 10B Lower edge 10C side part 10D Through hole (perforated section) 11 Air intake 12 Face Door 20 Switching device X Roof slope direction X

Claims

1. A snow-resistant roof structure with a double-layer structure is provided on the exterior side of an existing roofing material having recesses and protrusions, in which a heat-shielding steel plate is installed with a material that has a high reflectivity against radiant heat, such as aluminum foil, attached to the inside of the steel plate, Multiple support members, each having a Z-shaped cross-section or an inverted V-shaped cross-section that widens from top to bottom, are attached along the roof flow direction of the recess in the existing roofing material. The contact portion between the heat-shielding steel plate and the support member is fixed and rigid with double-sided tape or screws. A snow-resistant roof structure characterized by the following features.

2. Multiple perforations are formed in the Z-shaped support member or the inverted V-shaped support member. By forming the aforementioned perforated portion, the weight of the Z-shaped support member or the inverted V-shaped support member is reduced. The snow-resistant roof structure according to feature 1.

3. A ventilation layer is formed between the aluminum foil or other material with high reflectivity to radiant heat and the existing roofing material. An opening and closing device is provided in the ridge portion formed of the heat-shielding steel plate, which opens and closes in response to the temperature of the outside air, and the amount of air ventilated in the ventilation layer is adjusted by opening and closing the opening and closing device. A snow-resistant roof structure according to claim 1 or 2.

Images