ES2553855T3 - Bottom cover strip for a sloping roof - Google Patents

Abstract

Bottom covering strip (10) for a sloping roof with a support layer (12) permeable to water and water vapor and a waterproofing layer (14) waterproof and permeable to water vapor permeable based on TPU, characterized because the thickness of the waterproofing layer (14) is sized such that the lower coating band (10) can be joined in a water impermeable and water vapor permeable manner with a lower coating band (10) of the same type additional by thermal welding and solvent welding, in which the lower lining band (10) has a water-impermeable and water-permeable TPU-based joint strip (16) along at least one of the edges of the support layer (12), which protrudes beyond this at least one edge, in which both the TPU of the waterproofing layer (14) and the TPU of the bonding strip (16) are an aromatic TPU .

Description

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DESCRIPTION

Lower cover strip for a sloping roof Technical field

The invention relates to a lower covering strip for a sloping roof with a water permeable and water vapor permeable support layer and a water impermeable and water vapor permeable TPU based waterproofing layer. In addition, the invention relates to a roof with a plurality of undercoat strips, overlapped and welded, water impermeable and water vapor permeable.

State of the art

The lower lining bands have the objective of protecting the uncovered roof first of all against the entrance of rain. After hard coating, snowdrift, splashing and rolling water and fine dust particles in the thermal insulation should be avoided. At the same time, water vapor, which can proceed as excess moisture from the construction moisture and inhabited areas of the roof, must be released through the thermal insulation with diffusion capacity and the lower covering band to the environment. In this regard, all thermal insulation placed between the roof winches can serve as temporary moisture storage, taking into account not to be below the rodo point, to which condensation water condenses. This can be avoided by installing a trap or vapor barrier that is placed under the roof in the roof construction.

If the stretched lower cover strip does not have water vapor permeability or too low, then excess moisture present in the roof area can condense on the lower cover strip, dampen the thermal insulation and, among other things, among others. things, diminish its function.

In the lower cover bands, among other things, a distinction is made between water-resistant bottom cover bands and rain-proof bottom cover bands. While it is true that rain-proof roof decks are as a rule rain-proof, in extreme places or special weather conditions they cannot nevertheless completely prevent the entry of torrential rain and snowdrift snow. A sub-cover is considered rainproof when its surface, including seam and butt joints between the individual lower liner bands, is made rainproof. In the rainproof sub-cover, penetrations, mounting parts and flanges must be made rainproof.

Unlike this, in the waterproof sub-cover, the perforations, the mounting parts and the flanges must be made impervious to water, so that the entire sub-cover is impervious to water. Only in this way can one generally speak of a water-impermeable roof construction, because roof roofs laid in the form of usual scales are usually only rainproof and, among other things, cannot completely prevent the entry of torrential rain. and snowdrift.

To create a waterproof subcoat, plastic bands are conventionally used, inter alia, TPU being suitable for this, i.e. urethane-based thermoplastic elastomers, because they are especially resistant to water and heat, soft and flexible, that way they can be processed well and they are particularly resistant to microbes. To join two bands of lower TPU lining between them next to each other, these are glued together, which requires the presence of an adhesive on or by the TPU layer.

However, there are also lower coating bands that have a waterproofing layer based on TPO (olefin-based thermoplastic elastomers). Such undercoat bands can also be heat welded together.

An additional property of the waterproofing layer is, in addition to water impermeability, water vapor permeability, which is also called diffusion capacity. This means that although the waterproofing layer is impermeable with respect to the water that can impact from the outside on the lower cladding band, it nevertheless lets out the water vapor from the inside of the building outwards due to the diffusion capacity and therefore prevents damage to thermal insulation or other objects present inside the building due to too high humidity.

The undercoat bands often also have a support layer, which is permeable to water and water vapor. A set of layers formed by a support layer and a waterproofing layer can be, in the case of a water impermeable and water vapor permeable waterproofing layer, in general water impermeable and water vapor permeable, so that in this way an embodiment with diffusion capacity and impervious to the water of a sub-cover can be implemented.

US 2005/0097857 A1 discloses a lower covering strip for a roof that is not a

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Asphalt base, in particular not based on bitumen, which has diffusion capacity and is impermeable to water. One or two layers of a thermoplastic material with diffusion capacity can be applied to a substrate layer.

Document DE 79 07 342 U1 describes a bitumen roof strip, which in a longitudinal edge has a bare, uncoated or unblasted bitumen layer, to be imperviously bonded to the water with a subsequent waterproofing layer.

Document DE 38 23 365 A1 discloses a roof covering element in the form of a rectangular insulating plate of heat-insulating material, in which, to shorten the assembly time at the construction site, a waterproofing band that serves To seal the roof it is laminated directly on the upper side of the insulating plate. The waterproofing band protrudes beyond the insulating plate by two adjacent edges between them for impervious bonding with the adjacent insulating plates.

Exhibition of the invention

The lower covering bands known to the state of the art have the disadvantage that they can only be joined together in a water impermeable manner and with diffusion capacity with a relatively high effort. In particular, additional bonding agents should be provided for water-impermeable and diffusible bonding between undercoat bands with a tPu-based waterproofing layer. On the contrary, the TPO-based undercoat bands that can be welded do not have the advantages of the TPU layer, among which are the special resistance to water and heat, the soft and flexible structure and thus the good Processing capacity as well as resistance to microbes.

The objective of the present invention is to provide a lower covering band belonging to the prior technical field, which enables an effective implementation of a water impermeable and water vapor permeable subcoat.

The objective is achieved by the object of claims 1, 10, 11 and 14 as well as 15. Preferred embodiments of the object of the invention are defined in the dependent claims.

According to the invention, a lower cover strip for a sloping roof with a water permeable and water vapor permeable support layer and a water vapor permeable and water vapor permeable waterproofing layer is characterized in that the thickness of The waterproofing layer is sized in such a way that the lower coating band can be joined in a water impermeable and water vapor permeable manner with a lower coating band of the same additional type by thermal welding and solvent welding.

In this regard, the lower covering band has a water-impermeable and water vapor permeable joint strip along at least one of the edges of the support layer, which protrudes beyond this at least one edge, and both the TPU of the waterproofing layer and the TPU of the bonding strip are an aromatic TPU.

An inclined roof means a roof which, according to DIN 1055, has an inclination of more than 7 degrees. Despite the inclination of the roof, for certain weather conditions it is advantageous or even necessary to provide a lower lining band not only rainproof, but also impermeable to water, to effectively avoid a snowdrift, torrential rain , ice formations and snow deposits and the like.

The water-impermeable and water-vapor-permeable TPU, which has the aforementioned advantages, is used as a particularly preferred material for a similar underlay strip. By means of the embodiment according to the invention it is possible to weld together the lower lining bands located next to each other thermally or by welding with solvents and therefore joining them impervious to water and permeable to water vapor.

Among the TPUs, mixtures of substances with a percentage of at least 80% by weight of TPU and up to 20% by weight of load should also be considered within the meaning of the invention. In this regard, corresponding charges can be used, for example to save material and / or for cost reduction.

In order to assess whether a lower covering band can be referred to as waterproof, the DIN 1928 standard and DIN 20811 standard must be used. If the tests according to them are satisfied, the bands are considered waterproof. Likewise, water impermeability and with it the utility of the invention are determined in a decisive manner by the requirements of the ZVDH (Zentralverband des Deutschen Dachdeckerhandwerkes, German Confederation of the Guild of Roofers), which provide for the existence of a defined oblique rain test at TU-Berlin (Technical University of Berlin).

The standard to be taken into account with regard to diffusion capacity is DIN 4108, part 3. In

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This is defined as Sd <0.5 m as Ifmite value for diffusion capacity. Therefore, a layer whose value of Sd is less than 0.5 m will be called a layer with diffusion capacity.

However, the value of Sd is also preferably less than 0.2 m. According to DIN 68800, an Sd <0.2 m must be respected and a corresponding layer considered as diffusing, when chemical wood preservatives must be dispensed with.

Particularly preferably, the Sd value of the lower covering band is less than 0.2 m and is between 0.02 m and 0.2 m.

In thermal welding, the temperature of the TPU layer is increased in such a way that it joins with another corresponding layer and is therefore welded homogeneously. In solvent welding, a solvent welding agent, for example tetrahydrofuran (THF), is applied to the waterproofing layer, which partially dissolves the TPU and thus enables welding between adjacent lower coating bands. In addition, they can also be used, for example, benzene or benzine. However, THF is especially preferred with respect to benzene or benzine or other solvents, among other things due to its short time of action and the short time necessary for the laying associated therewith. Preferred solvents can be found in general among alkanes, alkenes, aromatic compounds, organic chlorine compounds, alcohols, esters, ethers or ketones.

The lower coating band according to the invention preferably consists of a water permeable and water vapor permeable support layer and a water impermeable and water vapor permeable waterproofing layer and does not require an additional adhesive layer as a bonding means. with an additional lower liner band or another layer that increases the stability of the lower liner band.

In the lower covering bands according to the preamble of claim 1, the support layer is responsible for the stability of the lower coating band, while the waterproofing layer is responsible for making the lower coating band waterproof. and permeable to water vapor. The TPU-based material used for the waterproofing layer is relatively expensive, so that conventionally it is about making the waterproofing layer, within the framework of the specifications in terms of its waterproofing property, as thin as possible.

According to the invention, this principle is abandoned and the thickness of the waterproofing layer is increased with respect to the state of the art. The thickness of the waterproofing layer is increased until a thermal welding is also possible with a waterproofing layer based on TPU, without the waterproofing layer or the support layer being damaged during thermal welding. This happens in the case of a conventional bottom covering band with a correspondingly thin waterproofing layer, so that the conventional bottom covering bands cannot be joined together by thermal welding. The same also applies to solvent welding, which for the same reasons cannot be applied on a TPU-based waterproofing layer that is too thin.

In order to be able to join adjacent lower covering bands in the most efficient way possible, the water-impermeable and water vapor permeable joint strip is provided according to the invention along at least one of the edges of the support layer, which protrudes beyond this song.

This bonding strip can be deposited, for example, during the production of the lower covering strip, on hot TPU, which is already on the support layer, and thus joins the TPU of the waterproofing layer. In addition, it is also possible, for example, for the bonding strip to be made integral with the waterproofing layer, that is to say that the waterproofing layer as such protrudes correspondingly beyond at least one of the edges of the coating layer. support such that a corresponding joint strip is formed. In addition, there are also other additional possibilities for generating or joining the joint strip with the lower covering band, for example by extracting the coating layer material or removing the support layer from the lower coating band.

Since the tie strip is also made of a water impermeable and water vapor permeable material, it is possible to join a lower liner band with another lower liner band in a water impermeable and water vapor permeable manner, so that a sub-cover can be completely completely impermeable to water and permeable to water vapor. In this regard, the joint strip as part of the lower liner band allows an especially effective bond between adjacent lower liner bands, because in this case no additional adhesive or other joint element should be deposited on the adjacent lower liner bands.

The "water impermeable" and "water vapor permeable" or "diffusible" features are subject to the inspection guidelines for works that are in force for roofs in Germany. The corresponding standards are found, for example, in DIN 68800 and DIN 4108, part 3 and they must also be used in this context for the definition of the properties mentioned above.

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The union strip is a strip based on TPU. The TPU-based tie strip also enables a waterproof and water vapor permeable roof covering with all the advantages of the TPU at welding points and facilitates welding of adjacent lower liner bands.

Both the TPU of the waterproofing layer and the TPU of the bonding strip are an aromatic TPU, the waterproofing layer and the bonding strip of the same material being preferably made. The aromatic TPU is especially well suited for welding and has the especially preferred properties already mentioned above of a TPU-based waterproofing layer.

Advantageously, the waterproofing layer has a thickness of at least 0.1 mm, preferably 0.1 to 0.2 mm, especially preferably 0.1 to 0.15 mm. Such a thickness of the waterproofing layer of the lower covering band is suitable for joining adjacent adjacent lower covering bands by welding, without the waterproofing layer and / or the support layer being damaged in this regard. In addition, the claimed thickness is suitable at the same time to carry out an effective production of a lower coating band, since no excess material is applied on the support layer.

Advantageously, the waterproofing layer has a mass per unit area of at least 100 g / m2, preferably 100 to 200 g / m2, especially preferably 100 to 150 g / m2. Corresponding surface unit masses mean that, with respect to the conventional waterproofing layers of a lower coating band of the preamble of claim 1, a mass application has taken place, which makes adjacent lower coating bands can be joined together by thermal welding or solvent welding.

Preferably the lower covering band is free of adhesive. In conventional undercoat bands with a TPO-based waterproofing layer, adhesives of some kind are necessary to glue the bottom coating band with an adjacent lower coating band. Even when, in the state of the art, the term "welding" is occasionally used for this purpose, it is really a glue in this respect, since the TPO layers of the corresponding waterproofing layers are not joined by themselves and directly between them. , but an adhesive has been incorporated into the lower covering band, which produces a waterproof connection between adjacent lower covering bands.

In a preferred embodiment, the tie strip protrudes at least 3 cm, preferably between 3 cm and 7 cm, especially preferably between 5 cm and 7 cm, beyond at least one edge. A joint strip, which protrudes beyond the edge mentioned above, allows a secure connection between adjacent lower lining bands, so that all of the lower lining bands can be made impervious to water and diffusible. . It thus meets the requirements of inspection of works in terms of a waterproof weld of two bands of lower coating between sf

In a preferred embodiment, the bonding strip is made integral with the waterproofing layer. A bonding strip of this type is deposited as described above, for example during the production of the lower coating strip, on hot TPU or is produced as part of the waterproofing layer that protrudes beyond the support layer.

Another preferred embodiment provides that the bonding strip is joined with the waterproofing layer by thermal welding and / or solvent welding. In this preferred embodiment, the bonding strip can be joined, after cooling of the waterproofing layer, with the waterproofing layer. That is, the bonding strip can be joined with the waterproofing layer by the same mechanism with which adjacent lower lining bands can be joined together. In this way, existing undercoat bands with a corresponding thickness of the waterproofing layer can also subsequently be provided with a tie strip according to the invention. However, the laying of the lower covering band is facilitated, since the joint strip should only be welded with a edge of a lower coating band and not with two contiguous edges of two lower coating bands.

Preferably, the support layer is a nonwoven fabric. The base of this nonwoven fabric may preferably be polyester or a mixed fiber containing polyester or a derivative thereof. A non-woven fabric support layer allows, on the one hand, an especially simple production of the lower covering band, since the waterproofing layer can be applied on the existing support layer then, without the waterproofing layer itself having to be especially stable. Thus, large surface underlay bands can also be generated efficiently. On the other hand, the support layer serves for the safety of the work during the laying of the lower covering bands, because it provides additional resistance to the lower coating band, so that the lower coating band can easily support a human adult, when he stands on the lower lining band. Basically, the lower liner band according to the invention can be used for all applications that require waterborne and water vapor permeable suspended lower coatings. In particular, by providing a water-impermeable and diffusible undercoat band, products can be dispensed with

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wood preservatives to protect the roof construction. The lower covering band according to the invention enables a particularly efficient laying of a sub-cover as well as an efficient production of the lower covering bands. By means of the bonding strip, adjacent lower covering strips can be directly connected between them, these being also, at the point of attachment, specifically the overlap between the joining strip and the adjacent lower covering strip, impermeable to water and with diffusion capacity .

Basically, it is also possible that the lower covering band has more than two layers, it being preferred that it only contains a support layer and a waterproofing layer. However, depending on the field of application, it may be advantageous to provide either on the waterproofing layer, between the waterproofing layer and the support layer, or under the support layer, one or more additional layers. However, in order to guarantee the water impermeability and diffusion capacity of the lower coating band in the case of a multi-layer embodiment, it should be that the additionally applied layers are in each case at least permeable to water vapor and do not damage the water impermeability of the waterproofing layer.

The lower covering band according to the invention can also have several joining strips, which protrude beyond several edges of the support layer. This can be provided, for example, in corner pieces of lower cover bands or in special lower cover elements for waterproofing penetrations, mounting parts or flanges.

A roof according to the invention contains a plurality of undercoat strips overlapped and welded, water impermeable and water vapor permeable, as described above. In this regard, the joint strip of a lower liner band is welded with an adjacent lower liner band such that the lower liner bands have a water-impermeable and water vapor permeable weld joint. Preferably, in this respect the joint strip is configured in a manner that is integral with the waterproofing layer of the lower covering band belonging thereto, so that only welding on one side of the joint strip is necessary. A roof of this type can be classified as impervious to water according to the guidelines of the ZVDH and is therefore suitable for effectively protecting a building, also in especially unfavorable weather conditions, against moisture.

Additional preferred embodiments are apparent from all of the claims as well as from the following description of the figures.

Brief description of the figures

Figure 1A shows a cross-sectional side view of a preferred lower cover strip for a sloping roof;

Figure 1B shows a cross-sectional side view of another preferred lower cover strip for a sloping roof;

Figure 1C shows a cross-sectional side view of an additional preferred lower cover strip for a sloping roof;

Figure 2 shows a plan view of two joined lower liner bands; Y

Figure 3 shows a plan view of a corner piece of a preferred lower cover strip.

Modes of realization of the invention

Figure 1A shows a side view of a preferred lower covering band 10 in a cross-sectional representation. A waterproofing layer 14 is arranged on a support layer 12, which is made of TPU. On the waterproofing layer 14 there is a joint strip 16 along a edge 15, which extends on both sides of the edge 15.

In this regard, the joint strip 16 extends over the distance 18 over the waterproofing layer 14 of the lower covering band 10 and protrudes over the distance 20 beyond the edge 15 of the support layer 12. The thickness 24 of the waterproofing layer 14 is represented in FIG. 1A as somewhat smaller than the thickness 23 of the support layer 12. On the contrary, the thickness 22 of the joint strip 16 corresponds to the thickness 24 of the waterproofing layer 14.

The bonding strip 16 and the waterproofing layer 14 not only have the same thickness, but are also made of the same material, particularly preferably aromatic TPU. The support layer 12 is made of a nonwoven fabric.

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The distance 18 or 20 of the union strip 16 ascends in the embodiment shown in Figure 1A in each case to 5 cm, the thickness 22 of the union strip 16 ascends, as does the thickness 24 of the layer of waterproofing 14, at 0.15 mm. In this regard, the waterproofing layer l4 has a mass per unit area of 150 g / m2.

Figure 1B shows a side view of a preferred lower covering band 10 in a cross-sectional representation, which resembles that of Figure 1A. However, another preferred embodiment is shown in FIG. 1B, in which the joint strip 16 is made integral with the waterproofing layer 14. The thickness 22 of the joint strip 16 is in this embodiment equal to the thickness of the waterproofing layer 14. The bonding strip 16 extends, as in the embodiment shown in Figure 1A, also by the overhang 20 beyond the edge 15 of the support layer 12. Otherwise Refer to the description in Figure 1A.

Figure 1C shows a further embodiment of a preferred lower covering band 10 in a cross-sectional representation, which resembles that of Figures 1A and 1B. However, in this regard, in Figure 1C the joint strip 16, which, as in the embodiment of Figure 1B, is made integral with the waterproofing layer 14, is folded and placed in the support layer 12 on the opposite side of the waterproofing layer 14. Moreover, this embodiment corresponds to that shown in Figure 1B.

Figure 2 shows a plan view of two lower cover strips 10.1, 10.2 located side by side, which are joined together by a joint strip 16.1 of the first lower cover band 10.1. On the side of the second lower covering band 10.2 opposite the joining strip 16.1 of the first lower covering band 10.1 is the joining strip 16.2 of the second lower covering band 10.2. Accordingly, an additional lower covering band could be applied along the edge of the second lower covering band 10.2, which is provided with the joining strip 16.2, on the second lower covering band 10.2 and joined therewith.

In this respect, the lower lining bands 10.1, 10.2 extend parallel to the edge, along which the connecting strips 16.1 and 16.2 run. Thanks to the waterproof connection and diffusion capacity of the two lower cover bands 10.1 and 10.2, all of the lower cover bands 10.1 and 10.2 can also be classified as waterproof and with diffusion capacity.

Figure 3 shows a preferred embodiment of a lower covering band 10, in which a joint strip 16 runs along second edges 26 and 28 of the lower covering band 10. In this regard, the two edges 26 and 28 of the lower covering band 10 run at right angles to each other in the embodiment shown in Figure 3.

Accordingly, by means of the embodiment of the lower covering band 10 shown in Figure 3, on the one hand, a water-impermeable joint with diffusion capacity between adjacent lower cover bands can be produced along its edge 26 longitudinal side and, on the other hand, it is also possible to join water-impermeable and water-permeable bands of lower lining 10, located behind each other, along the edge 28 by means of the connecting strip 16.

The embodiments shown in the figures can be varied practically in any way from the geometric point of view, so that in particular curved or angled bottom covering bands can also be made.

Claims (9)

one. 10 fifteen twenty 2. 25 3. 30 4. 5. 35 6. 40 7. 8. 45 9. 50 10. 55 eleven. 60 Bottom cover strip (10) for a sloping roof with a support layer (12) permeable to water and water vapor and a waterproofing layer (14) waterproof and water vapor permeable based on TPU, characterized in that the thickness of the waterproofing layer (14) is sized such that the lower coating band (10) can be joined in a water impermeable and water vapor permeable manner with a lower coating band (10) of the same additional type by thermal welding and solvent welding, in which the lower covering band (10) has a water-impermeable and water-vapor permeable TPU-based joint strip (16) along at least one of the edges of the support layer (12) , which stands beyond this at least one song, in which both the TPU of the waterproofing layer (14) and the TPU of the bonding strip (16) are an aromatic TPU. Bottom covering strip (10) according to claim 1, wherein the waterproofing layer (14) and the bonding strip (16) are made of the same material. Bottom covering strip (10) according to claim 1 or 2, wherein the waterproofing layer (14) has a thickness of at least 0.1 mm, preferably 0.1-0.2 mm, especially preferably 0 , 1-0.15 mm. Bottom covering strip (10) according to one of the preceding claims, wherein the waterproofing layer (14) has a mass per unit area of at least 100 g / m2, preferably 100-200 g / m2, especially preferably 100-150 g / m2. Lower covering strip (10) according to one of the preceding claims, wherein the lower covering strip (10) is free of adhesive. Bottom covering strip (10) according to one of the preceding claims, wherein the joint strip (16) protrudes at least 3 cm, preferably between 3 cm and 7 cm, especially preferably between 5 cm and 7 cm beyond At least one song Bottom covering band (10) according to one of the preceding claims, wherein the joint strip (16) is made integral with the waterproofing layer (14). Bottom covering strip (10) according to one of claims 1 to 7, wherein the joint strip (16) joins the waterproofing layer (14) by thermal welding and / or solvent welding. Bottom covering band (10) according to one of the preceding claims, wherein the support layer (12) is a nonwoven fabric. Roof with a plurality of underlay strips (10.1, 10.2) overlapped and welded, waterproof and water vapor permeable according to one of the preceding claims, wherein the joint strip (16.1) of a lower liner band (10.1) is welded with an adjacent (lower liner 10.2) band such that the lower liner bands (10.1, 10.2) have a weld joint Water impermeable and water vapor permeable. Method for producing a lower covering strip (10) for a sloping roof according to one of claims 1 to 9, comprising the following steps: apply a waterproofing layer (14) waterproof and water vapor permeable based on aromatic TPU on a support layer (12) permeable to water and water vapor and joining a water-impermeable and water vapor permeable union strip (16) based on aromatic TPU with the waterproofing layer (14) along at least one of the edges of the support layer (12), 5 10 fifteen twenty 25 30 35 so that the union strip (16) protrudes beyond the edge. Method according to claim 11, further comprising heating the waterproofing layer (14), before joining the bonding strip (16) with the waterproofing layer (14), in which the joint strip (16) joins, when deposited on the waterproofing layer (14) heated along at least one of the edges of the support layer (12), with the waterproofing layer (14 ). Method according to claim 11, wherein the joint strip (16) is joined, by thermal welding and / or solvent welding along at least one of the edges of the support layer (12), with the layer waterproofing (14). Method for producing a lower covering strip (10) for a sloping roof according to one of claims 1 to 9, comprising the following steps: apply a waterproofing layer (14) waterproof and water vapor permeable based on aromatic TPU on a support layer (12) permeable to water and water vapor, wherein the waterproofing layer (14) protrudes beyond at least one edge of the support layer (12) in such a way that a water-impermeable and water vapor permeable joint strip (16) is formed, wherein the joint strip (16) is preferably formed by extracting material from the waterproofing layer (14) with respect to at least one of the edges of the support layer (12) and / or by removing material of the support layer (12) with respect to the waterproofing layer (14) along at least one of the edges of the support layer (12). Method for laying several overlapping strips (10) overlapping according to one of claims 1 to 10 on a roof, wherein the joint strip (16.1) of a lower liner band (10.1) is thermally welded and / or welded with solvents with an adjacent lower liner band (10.2), so that the lower covering bands (10.1, 10.2) have a water-impermeable and water vapor permeable weld joint.