Cladding element for a building

Abstract

The invention relates to a cladding element (1) for a building or a part of a building, in particular for a roof, wherein the cladding element (1) has a contact surface (2) facing the building during use and an outer structure (8) facing the environment of the building during use, wherein the outer structure (8) is determined by a base material of the cladding element (1). According to the invention, the outer structure (8) has a plurality of reflective surfaces (3) for reflecting sunlight, in particular IR radiation (100), and a plurality of absorption surfaces (4) for the absorption of sunlight, in particular IR radiation (100), wherein the reflective surfaces (3) reflect the sunlight, in particular the IR radiation (100), to a greater degree than the absorption surfaces (4) and / or wherein the absorption surfaces (4) absorb the sunlight, in particular the IR radiation (100), to a greater degree than the reflective surfaces (3). The invention also relates to methods for producing a cladding element (1).

Description

[0001] Cladding element for a building

[0002] The invention relates to a cladding element for a building or a part of a building, in particular a roof, wherein the cladding element has a support surface facing the building during use and an outer structure facing the building's surroundings during use, wherein the outer structure is defined by a base material of the cladding element. Furthermore, the invention relates to a roof clad with the cladding element.

[0003] Furthermore, the invention relates to a method for producing a cladding element for a building or a part of a building, in particular for a roof.

[0004] Buildings, especially roofs, are often fitted with cladding elements to protect them from the elements. Reflective cladding elements are well-known examples, as they are designed to prevent the building from overheating in summer.

[0005] For example, the application of a reflective layer with high specific electrical conductivity to a roof covering is known from document DE 203 15 042 U1.

[0006] However, this usually reduces the natural warming of the building by solar radiation, even in cooler seasons, requiring additional heating energy. Furthermore, roofs typically reflect light and can thus create an unwanted glare effect.

[0007] For example, document US 3,001,331 proposes a metal cladding attached to the roof covering, which has a horizontal reflective surface and a vertical absorption surface that absorbs light and heat and is visible from the street. The disadvantage of this arrangement is that the roof is less weather-resistant due to the large surface area exposed to wind, rain, and snow, resulting in a reduced roof durability.

[0008] The object of the invention is to provide a cladding element of the type mentioned above for a building or a part of a building, in particular for a roof, with which cladding element, when used in a building, heating of the building by solar radiation can be effectively and efficiently regulated in all seasons and which cladding element is particularly weather-resistant and durable.

[0009] A further aim is to specify a method of the type mentioned at the outset for producing a cladding element for a building or a part of a building, in particular for a roof, with which cladding element, when used in a building, heating of the building by solar radiation can be efficiently regulated in all seasons and which cladding element is particularly weather-resistant and durable.

[0010] The object is achieved by a cladding element according to claim 1. For a cladding element for a building or a part of a building, in particular for a roof, wherein the cladding element has a support surface which, when in use, faces the building and has an outer structure which, when in use, faces the surroundings of the building, wherein the outer structure is predetermined by a base material of the cladding element, it is provided according to the invention that the outer structure has a plurality of reflection surfaces for reflecting solar radiation, in particular IR radiation, and a plurality of absorption surfaces for absorbing solar radiation, in particular IR radiation, wherein the reflection surfaces reflect the solar radiation, in particular the IR radiation, more strongly than the absorption surfaces and / or wherein the absorption surfaces absorb the solar radiation, in particular the IR radiation, more strongly than the reflection surfaces.

[0011] The cladding element protects the building from environmental influences at any time

[0012] This can be achieved particularly effectively and efficiently in any season. The reflective surfaces can reflect solar radiation, especially IR radiation, and heating of the building in summer can be reduced or avoided. During use, the reflective surfaces and the absorption surfaces heat up to different degrees, so that air turbulence occurs above the cladding element, which also contributes to cooling. This can be achieved particularly efficiently if the reflective surfaces and the absorption surfaces are arranged alternately. The absorption surfaces enable the absorption of solar radiation, especially IR radiation, and can thus contribute to a natural warming of the building in winter. Solar radiation has a spectrum ranging from hard X-rays to long radio waves, with a continuous spectrum in a wavelength range from around 140 nm to around 10 cm.Infrared radiation with a wavelength of 780 nm to 1 mm is typically the main contributor to the heating of bodies on the Earth's surface. By specifically reflecting and absorbing this radiation, the heating of bodies, such as buildings, can be specifically regulated. The large number of reflection and absorption surfaces defined by the base material makes the cladding element particularly durable and stable. The aforementioned IR radiation, also known as infrared radiation, is typically infrared radiation from solar radiation. Infrared radiation is typically electromagnetic radiation with an electromagnetic wavelength of 780 nm to 1 mm, in particular 780 nm to 50 pm, preferably 780 nm to 3 pm.As a rule, sunlight refers to a portion of the electromagnetic spectrum of sunlight from 380 nm to 1 mm, in particular 380 nm to 50 pm, preferably 380 nm to 3 pm. Advantageously, heating of the building due to solar radiation, in particular due to irradiation of the cladding element with solar radiation, can be effectively and efficiently regulated, especially in all seasons.

[0013] Typically, with respect to solar radiation, particularly its infrared radiation, the reflectance of the reflecting surfaces is greater than the reflectance of the absorbing surfaces and / or the absorbance of the absorbing surfaces is greater than the absorbance of the reflecting surfaces. The respective reflectance can be an average reflectance. The respective absorbance can be an average absorbance. The reflectance or absorbance relates in particular to the aforementioned wavelength ranges of solar radiation. It is advantageous if the reflectance of the reflecting surfaces is greater than 0.5, in particular greater than 0.75, preferably greater than 0.9, and / or the absorbance of the absorbing surfaces is greater than 0.5, in particular greater than 0.75, preferably greater than 0.9.

[0014] Advantageous designs result from the following features:

[0015] A cladding element is particularly effective and durable if it has 8 to 4000, in particular 11 to 3000, reflection surfaces and / or 8 to 4000, in particular 11 to 3000, absorption surfaces.

[0016] The cladding element is typically monolithic. The outer structure is typically formed by an outer surface of the cladding element. The outer surface and the support surface are typically arranged on opposite sides of the cladding element. Typically, the outer surface and / or the support surface are each oriented substantially parallel to a longitudinal direction and parallel to a width direction of the cladding element. Typically, a height direction of the cladding element is oriented orthogonal to the longitudinal direction and orthogonal to the width direction of the cladding element. Typically, a height extension of the cladding element oriented in the height direction is smaller than a length extension oriented in the length direction and smaller than a width extension of the cladding element oriented in the width direction.The height direction is usually oriented from the support surface to the outer surface. It is advantageous if the cladding element is predominantly, especially essentially, made of the base material.

[0017] In order to regulate the effect of solar radiation particularly effectively and efficiently, it can be provided that a size ratio between all reflection surfaces and all absorption surfaces of the cladding element is from 90:10 to 50:50, in particular from 70:30 to 60:40. The size ratio usually refers to the surface area of ​​the reflection surfaces or absorption surfaces. It is advantageous if the reflection surfaces and absorption surfaces are arranged alternately along a direction of arrangement. This has proven advantageous in use due to a temperature difference that usually occurs between the reflection surfaces and absorption surfaces for the formation of convective currents, in particular air vortices. This enables a more homogeneous temperature distribution along the outer structure.In use, the arrangement direction typically corresponds to the inclination direction of a part, in particular the roof, of a building on which the cladding element is arranged. This applies in particular to a plan view of the part, in particular the roof, of the building.

[0018] The cladding element typically has an upper end and a lower end in a direction parallel to the outer surface. In use, the lower end is typically positioned lower than the upper end. The orientation direction of the cladding element is typically oriented from the upper end to the lower end. The orientation direction can be parallel to the arrangement direction or the arrangement direction itself. This is particularly true when viewed from above.

[0019] Top view usually refers to a view orthogonal to the outer surface of the cladding element or parallel to the height direction of the cladding element.

[0020] It can be provided that the outer structure is of stepped design. Typically, the reflective surfaces in the stepped arrangement or design face the upper end of the cladding element, which is designed in particular for attachment to a building. The absorption surfaces usually face the lower end of the cladding element. As a rule, in use, the lower end is arranged closer to the ground than the upper end. Typically, the upper end and the lower end are arranged opposite one another along the outer surface of the cladding element, in particular in the arrangement direction. In addition to or instead of the stepped arrangement, it can be provided that the reflective surfaces and the absorption surfaces are arranged alternately.In order to be able to regulate the effect of solar radiation in a particularly targeted manner, it can be provided that the reflection surfaces are each arranged at an angle α, in particular at an angle α of 70° to 179°, to a respective neighboring, in particular adjacent, absorption surface. The angle α can in particular be 80° to 153°, preferably 85° to 120°. Depending on the application conditions, it can also be efficient if the angle α is 105° to 135°, in particular 110° to 130°. It can be provided that the reflection surfaces each extend from a lower vertex facing the support surface of the cladding element to an upper vertex facing the environment. The reflection surfaces are therefore usually facing the upper end of the cladding element.It can further be provided that the absorption surfaces each extend from one of the upper vertices to the lower vertex, which is arranged between the absorption surface and a further reflection surface. This applies in particular in a cross-section of the cladding element that is orthogonal to the outer surface, wherein the cross-section occurs in particular along the arrangement direction. The absorption surfaces therefore usually face the lower end of the cladding element. This arrangement allows the effect of solar radiation on the building to be regulated particularly effectively and efficiently. In particular, glare from the cladding element can be avoided, preferably to a large extent, since the non-reflective or less reflective absorption surfaces are largely visible from a street view.The angle a of 70° to 179° is particularly suitable for temperate climates with latitudes from approximately 23° 27' to approximately 66° 34' north or south. The most efficient design in each case can be determined based on the precise geographical location of the building and the arrangement of the cladding element on the building. In particular, alternating reflection surfaces and absorption surfaces with upper vertices and lower vertices can be connected to one another in the cross-section of the cladding element, with upper vertices and lower vertices alternating along the outer structure or outer surface. The respective lower vertex is usually lower in relation to a height direction of the cladding element than the two upper vertices, between which the lower vertex is arranged.If the reflection surfaces are arranged at an angle a to the absorption surfaces, they also point towards the upper end of the cladding element, while the absorption surfaces point towards the lower end of the cladding element.

[0021] To provide a particularly stable cladding element, the upper and lower vertices can have a height difference d of 0.05 cm to 5 cm. This typically refers to the upper and lower vertices, which correspond to the respective reflection and absorption surfaces. The outer structure thus has a low profile height and is therefore particularly weather-resistant. Furthermore, a uniform overall visual impression can be created.

[0022] The reflection surfaces and absorption surfaces can be directly adjacent to each other or spaced apart from each other.

[0023] A transition region can be formed between the reflection surfaces and the absorption surfaces. Likewise, a transition region can be formed between the absorption surfaces and the reflection surfaces. It is advantageous if a transition region is formed between adjacent, in particular adjacent, reflection surfaces and absorption surfaces. For example, a transition region can be formed between a respective reflection surface and an absorption surface adjacent to the reflection surface. The transition region can be part of the respective reflection surface and / or absorption surface. Alternatively, it can be expedient for the transition region not to be part of the respective reflection surface and / or not to be part of the respective absorption surface. The absorption surfaces and reflection surfaces can be separated from one another by the transition regions.The outer structure in the transition area can have an edge, a bevel or a curve, in particular can be implemented by such a bevel. The stability and durability of the cladding element can be improved as a result. A cladding element is particularly stable if it has a bevel with a length of 0.1 cm to 2 cm, in particular 0.3 cm to 1 cm, in the transition area, in particular is implemented by such a bevel. Alternatively, a curve with a radius of 0.1 cm to 2 cm, in particular 0.3 cm to 1 cm, can also be provided in the transition area, in particular the transition area can be implemented by such a curve. This can effectively reduce the coverage of the absorption surfaces and reflection surfaces with dirt and / or rainwater.

[0024] The reflection surfaces and / or the absorption surfaces can be flat. The vertices can each be formed by an intersection point of an extension of the reflection surfaces or the absorption surfaces.

[0025] The cladding element is particularly weather-resistant if at least one, in particular each, reflection surface is concave or convex. Additionally or instead, at least one, in particular each, absorption surface can be concave or convex. This arrangement allows rainwater to be drained away particularly effectively or efficiently along the outer structure. Furthermore, concave reflection surfaces and / or convex absorption surfaces can reduce glare and increase reflection or absorption. It has proven particularly useful if at least one reflection surface is concave and at least one absorption surface is convex. This applies in particular in a cross-section through the cladding element that is orthogonal to the outer surface, preferably parallel to the direction of alignment or arrangement.The respective vertex can lie at the intersection point of an extension of a spanned surface of the reflection surface and an extension of a spanned surface of the absorption surface. The spanned surface can be defined by, in particular, opposite edges of the respective reflection surface or

[0026] absorption surface. In a cross-section of the cladding element that is orthogonal to the outer surface and preferably parallel to the direction of alignment, the respective clamping surface usually runs through end points of a contour of the respective reflection surface or absorption surface. It is advantageous if at least one, in particular several, of the reflection surfaces are shaped parabolically, at least in sections. As a result, the reflection surfaces can efficiently and directedly reflect solar radiation away from a close range or, preferably, reflect it upwards. This applies in particular in a cross-section that is orthogonal to the outer surface, preferably parallel to the direction of alignment. It is advantageous if at least one, in particular several, of the reflection surfaces are shaped parabolically, at least in sections. This can be implemented, for example, with one or more parabolic-shaped depressions in the reflection surface.The aforementioned configurations preferably apply to several, in particular a majority, preferably essentially all, of the reflection surfaces and / or absorption surfaces of the cladding element. Reflection surfaces or absorption surfaces shaped in this way have proven advantageous, particularly due to their radiation-directing ability, for temperature distribution planning, especially in urban areas, and for geoengineering.

[0027] To improve water flow and increase weather resistance, the reflective surfaces and / or absorption surfaces can be arranged in a striped, wavy, triangular, or diamond-shaped pattern. It is advantageous if the reflective surfaces and / or absorption surfaces each have a striped, wavy, triangular, or diamond-shaped side line. The respective side line can be an edge between adjacent, in particular contiguous, reflective surfaces and absorption surfaces. Preferably, such an edge can be present between a reflective surface and an absorption surface adjacent to it, in particular adjacent to it.The respective side line can be an edge between a respective reflection surface and the transition region adjacent to the reflection surface and / or an edge between a respective absorption surface and the transition region adjacent to the reflection surface. This has proven advantageous in use for generating air convection, in particular air turbulence, in order to promote a more homogeneous temperature distribution along the cladding element. It is advantageous if, in a diamond-shaped arrangement or diamond-shaped side line, the diamond shape is formed with four side line segments adjoining one another at an angle, wherein the side line segments preferably do not adjoin one another at right angles. It is advantageous if the reflection surfaces and / or absorption surfaces are arranged such that one of the diagonals of the respective diamond shape is oriented substantially parallel to the arrangement direction.

[0028] An effective or efficient cladding element can be provided if the reflective surfaces and the absorption surfaces are arranged in a strip-like manner. The cladding element is particularly stable if the reflective surfaces each have a strip width from the lower vertex to the upper vertex of 0.05 cm to 10 cm, in particular from 0.1 cm to 5 cm, or if the absorption surfaces each have a strip width from the upper to the lower vertex of 0.05 cm to 10 cm, in particular from 0.1 cm to 5 cm.

[0029] An effective, efficient, and stable cladding element can also be provided if the reflective surfaces are arranged in a diamond shape and the absorption surfaces preferably surround the reflective surfaces in a zigzag strip pattern. A strip-shaped, in particular rectangular, absorption surface can be arranged between adjacent reflective surfaces. Typically, the respective reflective surface is diamond-shaped. The reflective surfaces are preferably arranged such that the diamonds are arranged in rows in the directions of both diagonals of the diamonds. It is advantageous if a strip-shaped, in particular rectangular, absorption surface is arranged between adjacent side line segments of the diamonds. The absorption surfaces then typically form a zigzag pattern. The diamonds can have the same shape and / or the same orientation and / or the same size.This arrangement ensures a particularly stable cladding element that conveys a visually uniform overall impression. The effect of the sun can be regulated particularly effectively if the diamond-shaped reflective surfaces each have a longitudinal diagonal with a length of 0.05 cm to 10 cm, in particular from 0.1 cm to 5 cm, from the lower vertex to the upper vertex, and / or if the diamond-shaped reflective surfaces each have a transverse diagonal arranged or aligned perpendicularly or at right angles to the longitudinal diagonal with a length of 0.05 cm to 10 cm, in particular from 0.1 cm to 5 cm. Effective or efficient regulation of the effect of the sun can be achieved in addition to or instead of this if the strip-shaped absorption surfaces each have a strip width of 0.05 cm to 10 cm, in particular from 0.1 cm to 5 cm, from the upper vertex to the lower vertex.

[0030] In order to improve water guidance, it can be provided that the reflection surfaces and / or the absorption surfaces have a lateral inclination. The lateral inclination can be present at least in sections. In particular, a predominant proportion of the respective reflection surface or the respective absorption surface can have a lateral inclination. The lateral inclination can relate to a view orthogonal to the height direction of the cladding element and orthogonal to the direction of alignment. The lateral inclination is usually designed such that, particularly in plan view, when the cladding element is in use, rainwater falling onto the cladding element can be guided at least partially transversely to the direction of alignment due to the lateral inclination. The reflection surfaces and / or the absorption surfaces can slope downwards or upwards towards the sides of the cladding element.The sides form the edge of the cladding element which connects the upper end to the lower end. In particular, it can be provided that the direction of fall of the lateral inclination is arranged at an angle, in particular at an angle of more than 0° to 90°, in particular from 1° to 89°, preferably from 5° to 85°, to a perpendicular to the upper end and / or to the lower end. Alternatively or additionally, the direction of fall of the lateral inclination can have an angle, in particular an angle of more than 0° to 90°, in particular from 1° to 89°, preferably from 5° to 85°, to the direction of alignment. This means that rainwater in particular can be drained away efficiently, in particular laterally or in a direction transverse to, in particular orthogonal to, the direction of alignment. In this way, a pronounced self-cleaning ability of the external structure can be achieved. In particular, a predominant proportion of the respective reflective surface orThe respective absorption surface must have such an inclination. This applies in particular to a cross-section of the cladding element orthogonal to the arrangement direction or orthogonal to the orientation direction.

[0031] Expediently, several, in particular a predominant proportion, of the reflection surfaces and / or absorption surfaces can be laterally inclined, in particular have a lateral inclination, such that the outer surface, in particular the reflection surfaces and / or absorption surfaces, form a channel along which rainwater can be guided during use. The channel is generally formed by the reflection surfaces and / or by the absorption surfaces, in particular their lateral inclination. Typically, the channel has, at least in sections, preferably substantially, a longitudinal direction oriented from the upper end to the lower end, in particular in a plan view of the cladding element. In particular, the channel has, at least in sections, preferably substantially, a longitudinal direction oriented parallel to the alignment direction, in particular in a plan view of the cladding element.Expediently, a plurality of such channels, in particular spaced apart from one another, can be formed. The channels can be regularly spaced from one another, usually in a direction substantially orthogonal to the longitudinal direction of the channels. The channels can be oriented substantially parallel to one another. For efficient water drainage, it is advantageous if the channel has a curved, preferably parabolic, bottom surface. This applies in particular to a cross-section of the channel oriented orthogonally to the longitudinal direction of the channel. The bottom surface can be formed in this way in sections, in particular predominantly, along the longitudinal direction of the channel.

[0032] The lateral inclination can be implemented by designing the reflection surfaces and / or absorption surfaces in a curved manner or, at least in sections, with planes inclined in the direction of the lateral inclination. The optimized water drainage achieved in this way is particularly important when the cladding element is a roof tile, in particular a roof tile, or when the cladding element is used for roof covering. In particular, this method enables efficient roof covering for roofs with a roof pitch of 10° to 30°, preferably 20° to 25°.

[0033] The reflection surfaces and / or the absorption surfaces can have a plurality of sections with opposing, in particular opposite, lateral inclinations, in particular in a direction orthogonal to the alignment direction. In this way, one or more channels can be formed with the sections. In particular, the respective reflection surface or absorption surface can be designed in this way, in particular have such sections. It is advantageous if, in particular in plan view of the cladding element, at least one channel runs along the alignment direction. The cladding element can expediently have a plurality of such channels. It can be practicable if a channel runs essentially in the center of the cladding element, in particular essentially along a center axis of the cladding element.For example, with respect to a central axis of the cladding element, in particular of the outer structure, running in the alignment direction, opposite sections of the reflection surfaces and / or the absorption surfaces can have opposing lateral inclinations, in particular each having a lateral inclination in the direction of the central axis. Central axis typically refers to an axis running, in plan view of the cladding element, along the alignment direction through the center of the cladding element, in particular the center of the outer structure. It is advantageous if, in a direction orthogonal to the alignment direction, at least one channel is arranged in a first half of the cladding element and / or at least one channel is arranged in a second half of the cladding element. Preferably, no channel is then arranged in the center, in particular along the central axis, of the cladding element.This allows for more efficient water drainage when arranging several adjacent cladding elements. The channels, in particular their longitudinal axes, preferably run substantially parallel to the arrangement direction and / or parallel to one another. An arrangement of the channel(s) applies in particular in a plan view of the cladding element. Typically, an arrangement or positioning of a channel relates to a center of the channel or to a longitudinal axis of the channel running through a center of the channel. At least one, in particular several, preferably a majority, particularly preferably substantially all, of the reflection surfaces and / or the absorption surfaces can have such lateral inclinations or sections.

[0034] Water drainage is supported if the reflective surfaces and / or absorption surfaces are shaped such that, in a plan view of the cladding element, the respective reflective surface and / or absorption surface has at least one side edge running transversely to the direction of alignment, wherein the side edge forms one or more maxima with respect to the direction of alignment. For this purpose, the side edge can be curved in the direction of alignment, at least in sections, or tapered in sections. The side edge is usually formed with a front end region of the reflective surface or absorption surface opposite to the direction of alignment. This applies in particular in a plan view of the cladding element.

[0035] An effective, stable, and easy-to-produce cladding element can be provided if the reflective surfaces have a coating that is more reflective of solar radiation, particularly IR radiation, than the absorption surfaces or more reflective than the base material of the cladding element. This is particularly advantageous if one surface of the absorption surfaces is formed from the base material. Additionally or instead, it can also be provided that the absorption surfaces have a coating that is more absorbent of solar radiation, particularly IR radiation, than the reflective surfaces or more absorbent than the base material of the cladding element.

[0036] The coatings can have reflection properties, in particular reflection degrees or absorption degrees, in accordance with the reflection properties, in particular reflection degrees or absorption degrees, specified for the reflection surfaces or absorption surfaces.

[0037] absorption levels.

[0038] The cladding element is particularly durable and stable if the base material of the cladding element is brick, especially brick made of clay or concrete.

[0039] In order to be able to regulate the effect of solar radiation on the building particularly effectively and efficiently, it is advantageous if the cladding element is a roof tile, especially a roof tile. The base material is usually made of, in particular, clay, usually fired clay, or concrete.

[0040] The object of the invention is also to provide a roof which effectively and efficiently regulates the heating of the building by solar radiation, in particular by irradiating the roof with solar radiation, in all seasons and which is particularly weather-resistant and durable.

[0041] This object is achieved by a roof, in particular a roof with a roof pitch of 10° to 70°, in particular of 10 to 30°, preferably of 20° to 25°, comprising at least one previously described cladding element, in particular comprising a plurality of previously described cladding elements.

[0042] In order to be able to regulate the effect of solar radiation in the roof or roof system effectively and efficiently at all times of the year, it is advantageous if the gradient of the absorption surfaces is greater than the gradient of the reflection surfaces.

[0043] To promote the warming of the building by solar radiation in winter, the reflection surfaces and absorption surfaces can be provided in a ratio of 100:0 to 40:60 when viewed from a vertical plane. This can also reduce the glare from the roof. To improve the reflection of solar radiation in summer, the reflection surfaces can each be arranged at an angle ß of -5° to -65°, in particular -10 to -45°, to the horizontal.

[0044] The absorption of solar radiation in winter is improved if the absorption surfaces are arranged at an angle θ of -60° to +60°, in particular of -30 to +30° to the vertical.

[0045] For high robustness, it has proven useful if the support surface has a surface structure that essentially corresponds to the outer structure, so that extreme values, in particular maxima and minima, of the outer structure and extreme values, in particular maxima and minima, of the surface structure lie opposite one another on the cladding element. The extreme values ​​are generally formed by elevations and depressions in the outer structure or the surface structure. Typically, maxima correspond to elevations and minima to depressions. It is preferred if the surface structure of the support surface essentially corresponds to the outer structure, with the surface structure and outer structure preferably being mirror images of each other. It has been shown that this is particularly advantageous for high structural accuracy during production, in particular by embossing, of the cladding element.

[0046] The aim is achieved by a method of the type mentioned at the outset for producing a cladding element described in this document, if a base body formed from a base material, preferably made of clay, is obtained, wherein the base material predetermines an outer structure of the cladding element, after which the base body is coated with a coating, in particular an engobe, after which the coating of the base body is at least partially removed in certain areas in order to form the reflection surfaces with, in particular by, areas of the base body coated with the coating and to form the absorption surfaces with areas of the base body from which the coating has been at least partially removed. A corresponding base body is or will usually be provided. In this way, a cladding element described in this document can be produced with the method in a cost-effective manner.This method can be called the first method.

[0047] The base body can expediently be coated with the coating by coating an outer surface of the base body, which outer surface defines the outer structure, with the coating in sections, in particular predominantly, preferably essentially entirely. The coating can be formed by one layer, in particular several spatially separated or contiguous layers.

[0048] Typically, the base body, particularly including the coating, is cured and / or fired, particularly if the base material is formed from clay and / or the coating is an engobe or glaze. Firing can expediently take place after curing. The coating can be removed in certain areas before firing, and in particular, if necessary, after curing. To prevent contamination of the reflective surfaces with dust, it is advantageous if the coating is removed in certain areas after firing. Curing can take place by drying the base body, particularly including the coating.

[0049] The region-by-region removal of the coating is usually carried out to such an extent that the absorption properties, in particular the absorption levels, of the regions from which the coating has been at least partially removed are suitable for forming the absorption surfaces. Typically, when the coating is removed region-by-region, the coating is removed to a predominant extent, in particular substantially, preferably completely. The absorption surfaces can be formed with, in particular by, the base material. The base material of the base body can be formed as described above with regard to the base material. The coating can be formed with, in particular substantially from, a glaze, an engobe, a lacquer, a plastic, a ceramic, enamel, pigments, sulfate, in particular barium sulfate, or a metallic coating. The coating is preferably formed with, in particular from, an engobe and / or a glaze.

[0050] The outer structure of the cladding element or base body can be practically produced by embossing. Typically, an embossed structure of the embossed mold is formed, in particular embossed, into the base body, in particular its base material, using an embossing mold to form the outer structure. The outer structure is usually formed corresponding to the embossed structure, usually as a negative structure of the embossed structure. The embossed structure is usually a negative structure of the outer structure. The embossed structure can be embossed by pressing the embossed structure and the base body together and / or by solidifying a flowable base material of the base body while contacting the embossed structure, so that the solidified base material has the outer structure.

[0051] The base body is usually formed predominantly, in particular substantially, from the base material. The base material can be formed predominantly, in particular substantially, from clay. It is advantageous if the clay is pigmented. In particular, the clay can be pigmented with manganese. This increases the absorption capacity of the base material. The base body can be shaped such that a surface of the base body forms the outer structure. The surface is usually formed from the base material. The coating is preferably an engobe. The engobe is usually formed predominantly, in particular substantially, from clay, in particular from a clay mineral mass. Although an engobe is preferred, the coating can also be formed with, in particular from, another material which has the reflective properties orabsorption properties, particularly for the formation of the reflection layer.

[0052] Preferably, the reflection surfaces are formed, usually after firing, with the areas of the base body coated with a coating, in particular engobe or glaze, together with the coating, in particular engobe or glaze, arranged thereon. The coating applied to the coated areas is then usually part of the base body. Usually, the absorption surfaces are formed after firing with, in particular, areas of the base body from which the coating, in particular engobe or glaze, has been removed, preferably essentially entirely, or to which no coating has been applied. Usually, the base body is fired together with the coating applied to it, usually in certain areas. Usually, the base material or areas of the base body from which the coating has been removed orto which no coating is applied have a greater absorption coefficient than the areas coated with the coating or the engobe. In particular, the absorption properties, in particular absorption coefficients, and / or reflection properties, in particular reflection coefficients, specified in this document for absorption surfaces can apply analogously to the base material or the areas of the base body from which the coating or engobe has been removed. The absorption properties, in particular absorption coefficients, and / or reflection properties, in particular reflection coefficients, specified in this document for reflection surfaces can apply analogously to the areas coated with the coating or engobe. This applies in particular after firing.

[0053] The method can be designed according to the features and effects described in this document in the context of a cladding element, in particular above. The same applies to the cladding element with regard to the method.

[0054] It is practical to coat the base body with the coating using spraying, spin-coating, 3D printing, especially 3D digital printing, and / or stencils. The coating can be removed in certain areas using a machining process, especially milling and / or grinding. A particularly high degree of practical implementation can be achieved if the engobe is removed in certain areas using a laser. In particular, irradiating the coating with laser radiation can liquefy and / or vaporize the coating to remove it in certain areas.

[0055] It is advantageous if the base body is selectively coated with the coating in such a way that areas of the base body coated with the coating essentially form the reflective surfaces. The coating can be applied to the base body to form a shape of the reflective surfaces. In particular, this makes it possible to essentially, preferably entirely, dispense with the need to remove the coating from the base body in certain areas, usually after firing. Typically, the absorption surfaces are then formed by areas of the base body to which the coating is not or will not be applied. This can be implemented in a particularly practical way if the coating is applied using 3D printing, in particular 3D digital printing, and / or using a temporary cover.Advantageously, in particular by means of 3D printing, the coating can be selectively applied essentially only to areas of the base body on which the reflective surfaces are formed with the coating.

[0056] When using a temporary cover, a section of the base body is usually covered, usually temporarily, with the temporary cover, so that an edge of the temporary cover at least partially, in particular substantially, defines the contour of an area to be coated, after which the area to be coated, usually including the edge of the temporary cover and / or including the temporary cover, is coated, after which the temporary cover is removed again. In this way, a selective coating of the base body can be achieved by not coating areas of the base body covered by the temporary cover with the coating. The section of the base body can represent an area of ​​an absorption surface. The coating can expediently be carried out by means of a spraying process and / or a spin-coating process. Several temporary covers can be used.Advantageously, one or more regions of the base body representing absorption surfaces can be covered at least partially, preferably essentially entirely, with one or more temporary covers. The regions to be coated can then be practically coated together with the temporary covers. The regions to be coated typically represent regions on which the reflection surfaces are formed upon application of the coating, in particular by the coating. The temporary cover can be arranged on the base body during the coating of the base body with the coating or positioned at a distance from the base body. The temporary cover can be removed before curing or before firing or during firing. The temporary cover can be formed by a stencil.After the areas to be coated have been coated, the stencil is usually removed from the base body, in particular detached from the base body. The stencil can be placed on the base body to cover the section of the base body and, after coating has been completed, can be removed from the base body again, in particular by moving the stencil away from the base body. The stencil can be formed with several stencil elements, which can in particular be assigned to different sections of the base body that are to be temporarily covered. The stencil is usually removed from the base body, in particular detached from the base body, before firing, in particular before curing. The reflective surfaces are generally formed with the coating applied to the areas to be coated.

[0057] It is practical if the temporary cover is removed with a change in the state of aggregation of the temporary cover. The temporary cover can expediently be arranged, in particular placed, on the base body for application of the coating. The temporary cover can be fixed to the base body. The temporary cover can be formed with, in particular by, one or more, in particular solid, cover elements. The cover elements can be formed with, in particular substantially from, plastic. For example, the respective cover element can be a plastic strip. The change in the state of aggregation can be a phase transition from a solid state to a liquid and / or gaseous state of the temporary cover, in particular of the cover elements. To change the state of aggregation, the temporary cover can be heated, usually with a heating device. The change in the state of aggregation orThe heating can take place during the firing process, in particular by firing. For example, the temporary cover can be arranged on the base body in a solid state. The base body, including the temporary cover, can then be coated with the coating. The temporary cover can then be converted into a liquid and / or gaseous state by heating the temporary cover, in particular during the firing of the base body, so that the temporary cover, including the coating arranged thereon, is removed, in particular by flowing off and / or evaporating the temporary cover. The temporary cover can advantageously be implemented with solid plastic strips, in particular as explained above.

[0058] Accordingly, the aim is achieved by a method of the type mentioned at the outset for producing a cladding element described in this document, if a base body formed from a base material, preferably made of clay, is obtained, wherein the base material predetermines an outer structure of the cladding element, after which the base body is selectively coated with a coating, in particular an engobe and / or glaze, such that coated regions of the base body essentially form the reflective surfaces. This method can be referred to as a second method. A corresponding base body is or will usually be provided. It is usually provided that regions of the base body to which the coating is not applied form the absorption surfaces. In this way, a cladding element described in this document can be produced with reduced effort using the method.This, in particular the second, method can be implemented alternatively, in addition to, or as part of the above, in particular the first, method. This, in particular the second, method can be designed according to the features and effects described in this document in the context of a cladding element or, in particular, the first method. The same applies analogously to the cladding element with regard to the first and / or second method.

[0059] This can be implemented particularly practically if the coating is applied by means of 3D printing, in particular 3D digital printing, and / or using a temporary covering, in particular a stencil. This can be implemented as described above.

[0060] The invention is described by way of example with reference to the following figures without limiting the general inventive concept:

[0061] Fig. 1 shows an exemplary cladding element as a roof tile with strip-shaped reflection surfaces and strip-shaped absorption surfaces.

[0062] Fig. 2 shows an alternative exemplary cladding element as a roof tile with strip-shaped reflection surfaces and strip-shaped absorption surfaces. Fig. 3 shows another alternative exemplary cladding element with wave-shaped reflection surfaces and wave-shaped absorption surfaces. Fig. 4 shows another alternative exemplary cladding element with diamond-shaped reflection surfaces and zigzag-strip-shaped absorption surfaces. Fig. 5a shows an exemplary cladding element with a strip-shaped outer structure in plan view.

[0063] Fig. 5 b shows the cladding element from Fig. 5 a in cross section

[0064] Fig. 5 c shows a detail of Fig. 5 b.

[0065] Fig. 5 d shows an alternative strip-shaped outer structure in cross section.

[0066] Fig. 5 e shows a detail of Fig. 5 d.

[0067] Fig. 6 shows the water flow in an exemplary alternative arrangement of the outer structure with strip-shaped reflection surfaces and strip-shaped absorption surfaces.

[0068] Fig. 7 shows the water flow in an exemplary alternative arrangement of the outer structure with strip-shaped reflection surfaces and strip-shaped absorption surfaces.

[0069] Fig. 8 shows the water flow in an exemplary alternative arrangement of the outer structure with triangular reflection surfaces and strip-shaped absorption surfaces. Fig. 9 shows the water flow in an exemplary alternative arrangement of the outer structure with triangular reflection surfaces and strip-shaped absorption surfaces. Fig. 10a shows a top view of an exemplary cladding element with diamond-shaped reflection surfaces and zigzag-strip-shaped absorption surfaces.

[0070] Fig. 10 b shows the cladding element from Fig. 10 a in cross section.

[0071] Fig. 10 c shows a detail of Fig. 10 b.

[0072] Fig. 11 shows the water flow in an exemplary cladding element with diamond-shaped reflection surfaces and zigzag-strip-shaped absorption surfaces in plan view.

[0073] Fig. 12 a shows a test setup for measuring the reflective properties. Fig. 12 b shows the test result for a cladding element according to Fig. 5 a.

[0074] Fig. 12 c shows the test result for a cladding element according to Fig. 10 a.

[0075] Fig. 13 a shows a test setup for measuring the absorbing properties. Fig. 13 b shows the test result for a cladding element according to Fig. 5 a.

[0076] Fig. 13 c shows the test result for a cladding element according to Fig. 10 a. Figures 1 to 4 show exemplary cladding elements 1 designed as roof tiles or roof tiles. The cladding elements 1 each have a support surface 2 for resting on the roof and an outer structure 8 with a plurality of reflection surfaces 3 and absorption surfaces 4. The reflection surfaces 3 are more reflective of solar radiation, in particular IR radiation 100, than the absorption surfaces 4 and the absorption surfaces 4 are more absorbent of solar radiation, in particular IR radiation 100, than the reflection surfaces 3. The outer structure 8 is predetermined by the base material of the cladding element 1.

[0077] This can be achieved, for example, by pressing, punching, or stamping a brick made of clay into the desired shape. A negative mold made of plaster, for example, can be used for this purpose. For a brick made of concrete, the outer structure 8 can be achieved by appropriately forming the negative mold.

[0078] The reflective properties can be achieved, for example, by applying a coating to the reflective surfaces 3. Glazes, engobes, lacquers, plastics, ceramics, enamel, pigments, or metallic coatings can be used for this purpose. Alternatively, the base material can also exhibit reflective properties, for example, due to its material properties or if reflective pigments or dyes are included. Barium sulfate, for example, can be used as a reflective pigment.

[0079] In this case, the absorbing properties of the absorption surfaces 4 can be achieved by providing them with a coating. Glazes, engobes, lacquers, plastics, ceramics, enamel, pigments, or metallic coatings can also be used here. Alternatively, the base material itself can also exhibit absorbing properties, for example, due to its material properties or if it contains absorbing pigments or dyes. Graphite, for example, is a suitable absorbing pigment.

[0080] There are various ways to apply the coating. For example, a brick blank can first be shaped, and then the coating can be applied. For this purpose, nozzles can be aligned, for example, to the reflection surfaces 3 or the absorption surfaces 4. This can also be done in a continuous process, with the blanks being transported on a conveyor belt.

[0081] Another possibility is to prepare the negative molds before the base material is formed. When the clay is fired or hardened, the coating bonds with the base material. Reflective materials can be glass, ceramic, metal, or pigments such as barium sulfate. Absorbent materials can be ceramic or pigments such as graphite or carbon black, but other materials such as bristles can also be used.

[0082] The outer structure in Fig. 1 has a plurality of strip-shaped reflection surfaces 3 and strip-shaped absorption surfaces 4. The reflection surfaces 3 and absorption surfaces 4 are arranged alternately and in a stepped manner. The areas of the reflection surfaces 3 are larger than the areas of the absorption surfaces 4.

[0083] The embodiment shown in Fig. 2 also has strip-shaped reflection surfaces 3 and strip-shaped absorption surfaces 4 arranged alternately and in a stepped manner. In this embodiment, twenty-three reflection surfaces 3 and twenty-three absorption surfaces 4 are provided.

[0084] In Fig. 3, the reflection surfaces 3 and the absorption surfaces 4 are wave-shaped, or the reflection surfaces 3 and / or the absorption surfaces 4 each have a wave-shaped side line. In this embodiment, the reflection surfaces 3 and the absorption surfaces 4 are also stepped. In the illustrated embodiment, eight reflection surfaces 3 and eight absorption surfaces 4 are formed.

[0085] The embodiment shown in Fig. 4 also has a plurality of step-like reflection surfaces 3 and absorption surfaces 4. The reflection surfaces 3 are diamond-shaped, and the absorption surfaces 4 surround the reflection surfaces 3 in a zigzag stripe pattern. Fig. 5a shows a plan view of a roof tile with a plurality of strip-shaped reflection surfaces 3 and strip-shaped absorption surfaces 4. The reflection surfaces 3 and absorption surfaces 4 are arranged alternately.

[0086] In the cross-section shown in Fig. 5 b, it can be seen that the reflection surfaces 3 and the absorption surfaces 4 are arranged alternately and in a stepped manner. In the embodiment shown, the reflection surfaces 3 are arranged at an angle α to the absorption surfaces 4. This arrangement results in a lower vertex 5 facing the support surface 2, at which one of the reflection surfaces 3 borders one of the absorption surfaces 4, and an upper vertex 6 facing the environment, at which the reflection surface 3 borders another absorption surface 4. The reflection surfaces 3 face the upper end 9 of the cladding element 1, while the absorption surfaces 4 face the lower end 10 of the cladding element 1.

[0087] The detailed view in Fig. 5 c shows that the angle a ranges from 70° to 179°, being 130° in the illustrated embodiment. The height difference d between the lower vertex 5 and the upper vertex 6 ranges from 0.05 cm to 5 cm and is 0.5 cm in the illustrated embodiment. The strip width of the reflection surfaces 3 thus measures 2.4 cm, and the strip width of the absorption surfaces 4 measures 0.85 cm each. The total area of ​​the reflection surfaces 3 is therefore in a ratio of approximately 74:26 to the total area of ​​the absorption surfaces 4.

[0088] Fig. 5d shows an alternative exterior structure 8 with strip-shaped reflection surfaces 3 and strip-shaped absorption surfaces 4. The reflection surfaces 3 are concave, and the absorption surfaces 4 are convex. This reduces glare and improves reflection. Furthermore, rainwater is drained even more effectively via the cladding element 1, contributing to the cleaning of the exterior structure 8, thus maintaining its long-term functionality. Concave reflection surfaces 3 and convex absorption surfaces 4 can also be provided in conjunction with other exterior structures 8.

[0089] Fig. 5 e shows a detail of the external structure from Fig. 5 d. In this case, the angle a refers to the spanned surfaces. Figs. 6 to 9 show various alternative external structures 8 with improved water guidance 7. To improve the drainage of rainwater, it can additionally be provided that the reflection surfaces 3 and the absorption surfaces 4 have a lateral inclination. The direction of fall is arranged at an angle to a perpendicular to the upper end 9 and the lower end 10. The reflection surfaces 3 and / or absorption surfaces 4 can expediently be laterally inclined such that the reflection surfaces 3 and / or absorption surfaces 4 form a channel along which rainwater can be guided during use. The water guidance 7 is preferably provided in a central region of the cladding element 1.

[0090] In Fig. 6, the reflection surfaces 3 and the absorption surfaces 4 are arranged alternately in an arc. The reflection surfaces 3 and the absorption surfaces 4 are each inclined such that a substantially central water guide 7 is created or a central channel is formed.

[0091] In Fig. 7, the reflection surfaces 3 and the absorption surfaces 4 are also arranged alternately in an arcuate manner, but with two adjacent, mirror-symmetrical arc segments. In these arc segments, the reflection surfaces 3 and the absorption surfaces 4 are inclined such that a central water guide 7 is formed in each case, or the respective arc segments are sections with which a channel is formed.

[0092] In Fig. 8, the reflection surfaces 3 are triangular, and the absorption surfaces 4 are arranged in strips underneath. In this embodiment, too, the reflection surfaces 3 and the absorption surfaces 4 have a lateral inclination that leads to a central water guide 7 or, with which, a central channel is formed.

[0093] In Fig. 9, the reflection surfaces 3 are also triangular, and the absorption surfaces 4 are arranged in strips below them, whereby in Fig. 9, two mirror-symmetrical segments arranged side by side are also provided. The water guidance 7 is achieved by a lateral inclination of the reflection surfaces 3 and the absorption surfaces 4, likewise centrally in both segments, or in such a way that the respective segments are sections, each of which forms a channel. Fig. 10a shows a plan view of a cladding element 1 designed as a roof tile. In this embodiment, the cladding element 1 has a plurality of diamond-shaped reflection surfaces 3 and zigzag-strip-shaped absorption surfaces 4. In the illustrated embodiment, approximately 300 reflection surfaces 3 and 28 absorption surfaces 4 are provided.

[0094] The cross-section in Fig. 10 b shows that the reflection surfaces 3 and the absorption surfaces 4 are arranged alternately and in a step-like manner, with the reflection surfaces 3 pointing towards the upper end 9 of the cladding element 1 and the absorption surfaces 4 pointing towards the lower end 10 of the cladding element 1.

[0095] In the detail shown in Fig. 10 c, it can be seen that the reflection surfaces 3 are arranged at an angle a to the absorption surfaces 4, wherein the angle can be from 70° to 179° and in the embodiment shown is 100°.

[0096] In an alternative embodiment not shown, the reflection surfaces 3 can be concave and the absorption surfaces 4 can be convex. The height difference d in the illustrated embodiments is typically 0.05 cm to 5 cm and measures, for example, 0.53 cm. As a rule, the height difference d in a cross-section orthogonal to an outer surface of the cladding element 1 having the outer structure refers to a highest point and lowest point in the height direction of the respective reflection surface 3 or absorption surface 4.

[0097] Fig. 11 shows the water guide 7 over a cladding element 1 as shown in Fig. 10 a to c.

[0098] Fig. 12 a shows a test setup for measuring the reflective properties of a cladding element 1. For this purpose, the cladding element 1 is aligned horizontally with the outer structure 8 facing upwards. Two radiators 101, which emit infrared radiation 100, are arranged above the upper end 9 and the lower end 10 of the cladding element 1, respectively, so that they are aligned at an angle to the outer structure. In the test setup shown, the angle is 45° to the horizontal. To determine the reflective properties, the temperature at the support surface 2 was measured. Fig. 12 b shows the measurement result for a cladding element 1 with strip-shaped reflection surfaces 3 and strip-shaped absorption surfaces 4, as shown in Figs. 5 a to 5 c. The IR radiation 100 emitted by the radiator 101 at the lower end strikes the reflection surfaces 3 to the extent of 60% and the absorption surfaces 4 to the extent of 40%.The IR radiation 100 emitted by the radiator 101 at the upper end hits approximately 94% of the reflection surfaces 3 and 6% of the absorption surfaces 4. The temperature at the support surface 2 was lower when the cladding element 2 was irradiated with the radiator 101 arranged at the upper end than when irradiated with the radiator 101 from the lower end.

[0099] Fig. 12 c shows the result of the measurement according to Fig. 12 a for a cladding element according to Fig. 10 a to 10 c. In this case, the IR radiation 100 of the radiator 101, which is arranged at the lower end, strikes the absorption surfaces 3 and the reflection surfaces 4 in a ratio of 30:70. The IR radiation 100 emitted by the upper radiator 101 strikes the reflection surfaces 3 to 100%. In this case, too, the temperature at the support surface 2 was higher when the cladding element 1 was irradiated from the lower end.

[0100] Fig. 13 a shows another test setup for measuring the absorption properties. In this case, a 1000-watt halogen spotlight 101 was arranged at a distance A of 60 cm from a cladding element 1. The cladding element 1 was mounted on a tiltable frame. In this case, too, the temperature was measured at the support surface 2. In the test setup shown, concrete cladding elements 1 were used, with the reflective surfaces 3 coated with a highly reflective coating. For this purpose, Cool Dry was applied twice according to the instructions. Cladding elements with a smooth outer structure 8, with and without a coating, were used as comparison elements.

[0101] Fig. 13 b shows the results for horizontal and vertical irradiation of the cladding element 1 with strip-shaped reflection surfaces 3 and strip-shaped absorption surfaces 4. In the embodiment shown, the roof pitch was set at an angle y of 35° to the horizontal. The reflection surfaces 3 therefore had an angle ß of -23° to the horizontal. The absorption surfaces 4 had an angle δ of -20° to the vertical. In the embodiment shown, with the horizontal orientation, the reflection surfaces 3 and the absorption surfaces 4 were irradiated in a ratio of 55:45. In the vertical orientation, the reflection surfaces 3 and the absorption surfaces 4 were irradiated in a ratio of 90:10. The heating was significantly greater with horizontal irradiation than with vertical irradiation.

[0102] Fig. 13 c shows the results for horizontal irradiation of a cladding element with diamond-shaped reflection surfaces 3 and zigzag-strip-shaped absorption surfaces 4. The roof pitch was set at an angle y of 25° to the horizontal. In this embodiment, the cladding element 1 had flat reflection surfaces 3 and flat absorption surfaces 4. The angle α between the reflection surfaces 3 and the absorption surfaces 4 refers to the spanned surfaces and was between 70° and 179°. As a result, the reflection surface 3 was arranged at an angle β of -10° to the horizontal and the absorption surface 4 at an angle δ of -5° to the vertical. In a further embodiment shown, the reflection surfaces 3 could be concave and the absorption surfaces 4 convex, as shown by the dashed line.During horizontal irradiation, the reflection surfaces 3 and the absorption surfaces 4 were irradiated in a ratio of approximately 40:60. During vertical irradiation, the ratio was 100:0. The heating during horizontal irradiation was significantly greater than during vertical irradiation.

Claims

Patent claims 1. Cladding element for a building or part of a building, in particular for a roof, wherein the cladding element (1) has a bearing surface (2) facing the building during use and an outer structure (8) facing the surroundings of the building during use, wherein the outer structure (8) is defined by a base material of the cladding element (1), characterized in that the outer structure (8) has a plurality of reflective surfaces (3) for reflecting solar radiation, in particular IR radiation (100), and a plurality of absorption surfaces (4) for absorbing solar radiation, in particular IR radiation (100), wherein the reflective surfaces (3) reflect the solar radiation, in particular the IR radiation (100), more strongly than the absorption surfaces (4) and / or wherein the absorption surfaces (4) absorb the solar radiation, in particular the IR radiation (100), more strongly than the reflective surfaces (3).

2. Cladding element according to claim 1, wherein the cladding element (1) has 8 to 4000, in particular 11 to 3000, reflective surfaces (3) and / or 8 to 4000, in particular 11 to 3000, absorption surfaces (4).

3. Cladding element according to one of claims 1 or 2, wherein the size ratio between all reflective surfaces (3) and all absorption surfaces (4) of the cladding element (1) is from 90 : 10 to 50 :

50.

4. Cladding element according to claims 1 to 3, wherein the outer structure (8) is stepped and / or wherein the reflective surfaces (3) and the absorption surfaces (4) are arranged alternately.

5. Cladding element according to one of claims 1 to 4, wherein the reflective surfaces (3) are each arranged at an angle α, in particular at an angle α of 70° to 179°, to the adjacent absorption surface (4), wherein it is particularly provided that the reflective surfaces (3) each extend from a lower vertex (5) facing the bearing surface (2) of the cladding element (1) to an upper vertex (6) facing the environment, and wherein the absorption surfaces (4) each extend from the upper vertex (6) to the lower The vertex (5) extends between the absorption surface (4) and another reflection surface (3).

6. Cladding element according to one of claims 1 to 5, wherein the upper vertex (6) and the lower vertex (5) have a height difference d of 0.05 cm to 5 cm.

7. Cladding element according to one of claims 1 to 6, wherein a transition area is formed between the reflective surfaces (3) and the absorption surfaces (4), wherein the outer structure (8) has an edge, a chamfer or a rounding in the transition area.

8. Cladding element according to one of claims 1 to 7, wherein at least one, in particular each, reflective surface (3) is concave or convex and / or wherein at least one, in particular each, absorption surface (4) is convex or concave.

9. Cladding element according to one of claims 1 to 8, wherein the reflective surfaces (3) and / or the absorption surfaces (4) are arranged in a strip-shaped, wave-shaped, triangular or diamond-shaped pattern.

10. Cladding element according to claim 9, wherein the reflective surfaces (3) and the absorption surfaces (4) are arranged in a strip shape, wherein it is particularly provided that the reflective surfaces (3) each have a strip width from the lower vertex (5) to the upper vertex (6) of 0.05 cm to 10 cm and / or that the absorption surfaces (4) each have a strip width from the upper vertex (6) to the lower vertex (5) of 0.05 cm to 10 cm.

11. Cladding element according to claim 9, wherein the reflective surfaces (3) are arranged in a diamond shape and the absorption surfaces (4) surround the reflective surfaces (3) in a zigzag stripe shape, wherein it is particularly provided that the diamond-shaped reflective surfaces (3) each have a longitudinal diagonal of 0.05 cm to 10 cm from the lower vertex (5) to the upper vertex (6), and / or wherein the diamond-shaped reflective surfaces (3) have a diagonal perpendicular to the longitudinal diagonal arranged transverse diagonals of 0.05 cm to 10 cm and / or wherein the strip-shaped absorption surfaces (4) each have a strip width of 0.05 cm to 10 cm, in particular of 0.05 cm to 5 cm, from the upper vertex (6) to the lower vertex (5).

12. Cladding element according to one of claims 1 to 11, wherein the reflective surfaces (3) and / or the absorption surfaces (4) have a lateral inclination, wherein it is particularly provided that the direction of the inclination is arranged at an angle, in particular at an angle of more than 0° to 90°, to a perpendicular to the upper end (9) and / or to the lower end (10).

13. Cladding element according to one of claims 1 to 12, wherein the reflective surfaces (3) have a coating which is more reflective for solar radiation, in particular IR radiation (100), than the absorption surfaces (4) and / or more reflective than the base material of the cladding element (1).

14. Cladding element according to one of claims 1 to 13, wherein the absorption surfaces (4) have a coating which is more absorbent for solar radiation, in particular IR radiation (100), than the reflection surfaces (3) and / or more absorbent than the base material of the cladding element (1).

15. Cladding element according to one of claims 1 to 14, wherein the base material of the cladding element (1) is brick, in particular brick made of clay or concrete.

16. Cladding element according to any one of claims 1 to 15, wherein the cladding element (1) is a roof tile.

17. Roof, in particular a roof with a roof pitch of 10° to 70°, comprising at least one cladding element (1) according to one of claims 1 to 16, in particular comprising a plurality of cladding elements (1) according to one of claims 1 to 16.

18. Roof according to claim 17, wherein the slope of the absorption surfaces (4) is greater than the slope of the reflection surfaces (3).

19. Roof according to one of claims 17 or 18, wherein in a view from the vertical the reflective surfaces (3) and the absorption surfaces (4) are visible in a ratio of 100 : 0 to 40 :

60.

20. Roof according to one of claims 16 to 19, wherein the reflective surfaces (3) are each arranged at an angle β of -5° to -65° to the horizontal, and / or wherein the absorption surfaces (4) are each arranged at an angle θ of -60° to +60° to the vertical.

21. Method for producing a cladding element (4) according to one of claims 1 to 16 for a building or part of a building, in particular for a roof, wherein a base body formed with a base material, preferably clay, is obtained, wherein the base material defines an outer structure (8) of the cladding element (1), after which the base body is coated with a coating, in particular an engobe, after which the coating is removed from the base body in areas in order to form the reflective surfaces (3) with areas of the base body coated with the coating and to form the absorption surfaces (4) with areas of the base body from which the coating has been removed.

22. Method according to claim 21, characterized in that the coating of the base body with the coating is carried out by means of a spraying process.

23. Method according to claim 21 or 22, characterized in that the partial removal of the coating is carried out by means of a machining process, in particular by means of milling, and / or by means of a laser.

24. Method for producing a cladding element (4) according to one of claims 1 to 16 for a building or part of a building, in particular for a roof, wherein a base body formed with a base material, preferably clay, is obtained, wherein the base material defines an outer structure (8) of the cladding element (1), according to which the base body is selectively coated with a coating, in particular an engobe, such that coated areas of the base body essentially form the reflective surfaces (3).

25. Method according to claim 24, characterized in that the coating is carried out by means of 3D printing, in particular 3D digital printing, and / or using a temporary covering, in particular a stencil.

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