JPH0415875Y2

JPH0415875Y2 -

Info

Publication number: JPH0415875Y2
Application number: JP1985058596U
Authority: JP
Priority date: 1985-04-18
Filing date: 1985-04-18
Publication date: 1992-04-09
Also published as: JPS61173646U

Description

【考案の詳細な説明】〔産業上の利用分野〕本考案は建築、構築物の内、外装の横張り壁体
を形成するのに有用で、かつ、弾力を利用して係
合力、防水性を強化すると共に化粧面が山状とな
らず美しい外観の外壁を形成しうるサイデイング
ボード（以下、単にボードという）に関する。〔従来の技術〕従来から使用されているこの種ボードとしては
特公昭51−29339号、実公昭51−11882号、
実公昭54−26649号などがある。しかしながら、
上記ボードにおいては種々の問題があつた。すな
わち、のボード（下見板）では雨水が風で吹き
つけられたりすると単なる平板同士の連結構造の
ため、雨水が裏面に漏洩し、胴縁、柱を腐食させ
たり、室内や押入れに湿気を与えたりする欠点が
あつた。またのボードでは下縁の傾斜部の立ち
上がり部までの長さが長いため引張り力に弱く、
目地なしの外装しか形成できない不利があつた。
しかも、本来は目地なしの外装なのに施工者の技
術によつて目地なし、目地ありのバラバラな幅の
目地からなる外装となると共に、施工の際に立ち
上がり部で負傷する危険があつた。また、この種
ボードは側面の形状が複雑で形成が難しく、か
つ、高価となり、その上、平坦部に補強用のリブ
もなく、反り、捩じれなとが大幅に化粧面に現れ
て美観を損なう欠点があつた。また、ボードはい
ずれも裏打材がないため化粧面の裏面に結露が生
じ、錆たり、壁体自体の断熱性、防音性に欠ける
と共に、化粧面の変形を阻止できず、しかもボー
ド自体が変形しやすく、かつ、連結力に欠ける欠
点があつた。〔考案の目的〕本考案はこのような欠点を除去するため、化粧
面の下端縁をコ字状の縦断面に形成し、かつ、化
粧面の長手方向と平行に縦断面が不等辺台形状で
あると共に、壁体を形成した際の横目地部の縦断
面と相似した形状の化粧溝を少なくとも１本以上
形成して目地をも壁体の１つの統一した模様とな
らしめて美しい外観とし、しかも上端に傾斜片、
目地下地部、およびリブ状の突条とから上記のよ
うな横目地を形成するための係合部を設け、か
つ、化粧面、係止部、係合部とで囲まれた凹部に
合成樹脂発泡体からなる断熱材を一体に充填した
ボードを提案するものである。〔考案の構成〕以下に、図面を用いて本考案に係るボードの一
実施例を詳細に説明する。すなわち、第１図は上
記ボードＡを示す斜視図であり、１は表面材で、
例えば表面処理鋼板、鋼板に亜鉛・ニツケル合金
をメツキした鋼板、アルミ・亜鉛合金メツキ鋼板
（商品名ガルフアン、ガルバリウム鋼板、スーパ
ージンク）、アルミニウム板、アルミニウム合金
板、銅板等の１種からなる金属板（平板、エンボ
ス加工板も含む）をロール、プレスで成形した
り、あるいは押出し成形などの１種により第２図
に示すような形状に形成したものである。すなわ
ち、表面材１は化粧面２、化粧溝３、係止部４、
係合部８とから形成したものである。さらに説明
を加えると、化粧面２は横長で、その表面に少な
くとも１本以上の化粧溝３を長手方向と平行に形
成したものである。この化粧溝３は主に化粧面２
の反り、捩じれ、ペコツキの防止と、ボートＡを
施工した際に壁体の横目地部と化粧溝３とを識別
しにくくして壁体を１つの統一した模様で美しい
外観とすると共に、大きさの割に立体感を醸し出
すのに役立つものである。さらに説明を加える
と、化粧溝３は縦断面が不等辺台形状、いわゆる
垂直な底面３ａと、底面３ａの上端縁を外方へ屈
曲し、化粧面２と直交する水平な上面３ｂと、化
粧面２と鈍角に後下がりに交わる下側の傾斜面３
ｃとから形成したものである。係止部４は化粧面
２の下端を内方に屈曲して縦断面をほぼコ字状と
したものである。さらに説明すると、係止部４は
化粧面２の下端をほぼ直角で屈曲したいわゆる水
平な底辺５と、底辺５の先端を上方に向かつて屈
曲した係止片６と、係止片６の先端をはぜ状に外
方、もしくは内方（図示せず）に屈曲した舌片７
とから形成したものである。この上記底辺５は化
粧溝３の深さに対応した長さとし、かつ、化粧面
２に対して直角、もしくは内方に鋭角に形成して
陰影による横目地部の立体感を助長するものであ
る。また、係止片６は後記する係合部８と大きい
面積で接触すると共に、施工の際のガイド、端縁
の波打ち防止（変形防止）および安定支持片、防
水面として機能するものである。さらに舌片７は
後記する突条１１との係合部分に毛細管現象が生
ずるのを防止する空隙の形成と、施工時に係止片
６の先端が刃物のように鋭利になるのを防止して
作業時の危険性をなくすのに役立つものである。
８は係合部で化粧面２の上端を前記化粧溝３の傾
斜面３ｃと同じ角度で後上がりに傾斜した傾斜片
９とその端縁を上方に垂直に延長した目地下地部
１０と目地下地部１０の表面に対し、鋭角に屈曲
し、ふたたび折り返して形成したリブ状の突状
と、突条１１の外側の面の下端部近傍を後上がり
状に傾斜した補強ばね片１１ａとその端縁を垂直
上方に屈曲した釘打設片１２と、釘打設片１２の
先端をはぜ状に屈曲した舌片１３とから形成した
ものである。さらに説明すると、傾斜片９は雨水
の流れをよくし、横目地部に雨水が貯留するのを
防止すると共に、横目地部の立体感を助長し、か
つ、働き幅を増大するのに役立つものである。ま
た、目地下地部１０は垂直な面、あるいは幾分内
方に傾斜した面からなり、横目地部の防水下地、
および係止片６のガイドとして役立つものであ
る。突条１１は係止片６をある弾力下で係合する
と共に、雨返し、および表面材１の変形防止のた
めの補強と係止片６と突条１１間の毛細管現象を
阻止するものである。なお、突条１１の傾斜角度
は係合力の強化のために舌片７が接触する面だけ
は傾斜していることが好ましい。また、補強ばね
片１１ａは突条１１の外側の面を直角に折り曲げ
たのに比べて釘βの打設面積を拡大すると共に、
ボードＡ自体を下地に向つて押圧する弾力を付与
するため角度θ（15〜45°）位で傾斜したものであ
る。なお、補強ばね片１１ａの下端は目地下地部
１０の裏面より突出させた形状である。これは下
地（図示せず）と目地下地部１０間に後記する断
熱材を充填し、熱橋を最小限とするためである。
また、釘打設片１２は、主に表面材１を雨水の漏
洩しない位置で第３図に示すように壁下地αに釘
βを介して固定し、釘孔からの錆の発生を防止す
るのに役立つものである。１３は舌片で主に施工
時の危険防止、および釘打設片１２の端部の波打
ちなどの変形を阻止するものである。１４は樋状
部で化粧面２、係止部４、係合部８の裏面によつ
て囲まれた部分であり、断熱材１５を充填する型
として機能するものである。断熱材１５は樋状部
１４に充填し、主にボードＡに断熱性を付与する
ものであり、副次的に芯材、クツシヨン材、補強
材、接着剤、防音材、防湿剤、防錆材として機能
するものである。その形状は樋状部１４に対応す
ると共に、係止部４近傍にほぼ３角形状、４角形
状（図示せず）などの窪部１６を設けたものであ
る。上記窪部１６は係止部４を係合部８に係合す
る際に、必要な空間である。また、断熱材１５の
素材は合成樹脂発泡体の１種からなり、原料で吐
出し、成形、硬化、自己接着させるもの、または
成形体などからなるものである。なお、断熱材１
５として成形体を用いる場合には表面材１、裏面
材１７との間に接着剤（図示せず）を用いる必要
がある。さらに説明すると合成樹脂発泡体として
は、例えばポリウレタンフオーム用樹脂、ポリイ
ソシアヌレートフオーム用樹脂、フエニールフオ
ーム用樹脂、およびこれらに難燃剤、難燃助剤
（硼砂、メタ硼酸ソーダ、炭酸カルシウム、水酸
化アルミニウム、三酸化アンチモン）、ベントナ
イト、パーライト粒、シラスバルーンの１種以上
を添加したものなどからなるものである。裏面材
１７は断熱材１５の裏面を被覆するものであり、
主にボードＡをサンドイツチ構造体とし、ボード
Ａ自体の機械強度を向上すると共に、不燃シー
ト、防水膜、遮熱シート、吸水シート、防音シー
ト、パツキング材などの機能として役立つもので
あり、例えばアスベスト紙、クラフト紙、アスフ
アルトフエルト、金属箔（Ａ、Fe、Pb、Cn）、
合成樹脂シート、ゴムシート、布シート、石膏
紙、水酸化アルミ紙、ガラス繊維不織布等の１
種、または２種以上をラミネートしたもの、ある
いは防水処理、難燃処理されたシートなどからな
るものである。〔施工例〕次に施工例について説明する。いま、第１図に
示すようなボードA₁，A₂を第３図に示すように
横張りして外壁を構成すると仮定する。そこで、
間柱、胴縁、防水シート等からなる壁下地（図で
は防水シートを使用しない場合を示す）αに第ｎ
段目のボードA₁の釘打設片１２を釘βを介して
固定する。次に第ｎ＋１段目のボードA₂の係止
部４を第ｎ段目の係合部８に係合し、ボードA₂
の釘打設片１２（図示せず）を上記と同様に壁下
地αに固定する。従つて外壁全体を構成するに
は、上記のような工程を順次、土台側から桁に向
かつて行なえばよい。なお、土台部分にはスター
タ（図示せず）、壁の縦目地、出、入隅等の部分
（図示せず）にはコーキング材、役物を用いる必
要がある。〔その他の実施例〕以上説明したのは本考案に係るボードＡの一実
施例にすぎず、第４図ａ〜ｅ、第５図ａ〜ｍ、第
６図ａ〜ｄ、第７図ａ〜ｅに示すように形成する
こともできる。すなわち、第４図〜第６図は表面
材１の各部の変形例で、第４図ａ〜ｅは化粧溝３
の変形例であり、第５図ａ〜ｍは係止部４の変形
例であり、第６図ａ〜ｄは係合部８の変形例であ
る。なお、第４図〜第６図において表面材１の板
厚は省略している。また、第７図ａ〜ｅは窪部１
６のその他の変形例である。なお、第４図〜第７
図を各々組み合わせてボードを製造することも可
能である。〔考案の効果〕上述したように本考案に係るボードによれば、
係止部と係合部の連結構造に毛細管現象が生ずる
こともなく、かつ、係止部の舌片、係合部の突条
によつて雨水がボードの内側に漏洩することがな
いので下地、あるいは壁内部を腐食しない特徴が
ある。また、ボードの固定は雨水の漏洩しない位
置としたため、釘孔からの錆の発生、雨水の漏洩
を防止できる利点がある。さらに、化粧面に少な
くとも１本の化粧溝を形成したため、強度が十分
に補強され、化粧面が山状になつたりすることが
なく美しい外観の壁体を形成できる特徴がある。
さらに、ボードを下地に固定する際には補強ばね
片が有効に作用し係合力の強化と化粧面の山状化
を防止するものである。しかも釘の打設面積を広
げ、表面材の有効利用を図つたものである。さら
に釘打設片を目地下地裏面より突出させて形成
し、該空隙に断熱材を充填したため、熱橋を最小
限に抑えた特徴がある。 [Detailed description of the invention] [Industrial application field] The invention is useful for forming horizontal walls for the interior and exterior of buildings and structures, and uses elasticity to increase engagement force and waterproofness. This invention relates to a siding board (hereinafter simply referred to as a board) which can be strengthened and form an outer wall with a beautiful appearance without having a decorative surface that becomes mountain-like. [Prior art] This type of board that has been used in the past includes Tokoku No. 51-29339, Utility Model No. 51-11882,
There is Jikko No. 54-26649. however,
There were various problems with the above board. In other words, if rainwater is blown by the wind on the board (closing board), the rainwater will leak to the back side because it is simply a connecting structure between flat plates, corroding the edges and pillars, and causing moisture in the room and closet. There were some drawbacks. In addition, because the length of the sloped part of the lower edge to the rising part of the board is long, it is weak against tensile force.
The disadvantage was that only an exterior without joints could be formed.
Moreover, although the exterior was originally without joints, due to the skill of the builder, the exterior was made up of joints of varying widths, some without joints, some with joints, and there was a risk of injury from the rising parts during construction. In addition, this type of board has a complicated side surface shape, making it difficult and expensive to form.Furthermore, there are no reinforcing ribs on the flat part, so warping and twisting appear on the decorative surface, spoiling the aesthetic appearance. There were flaws. In addition, since all of the boards do not have a backing material, condensation forms on the back of the decorative surface, causing rust, and the wall itself lacks heat insulation and soundproofing properties.In addition, it cannot prevent the decorative surface from deforming, and the board itself deforms. The disadvantage was that it was easy to connect and lacked connection strength. [Purpose of the invention] In order to eliminate such drawbacks, the present invention forms the lower edge of the decorative surface into a U-shaped longitudinal section, and the longitudinal section parallel to the longitudinal direction of the decorative surface is scalene trapezoidal. At the same time, at least one decorative groove having a shape similar to the vertical cross section of the horizontal joint portion when the wall is formed is formed to make the joint a unified pattern of the wall and create a beautiful appearance. Moreover, there is a sloped piece on the top end.
An engaging part is provided to form the above-mentioned horizontal joint from the joint base part and the rib-like protrusion, and it is combined into a recessed part surrounded by the decorative surface, the locking part, and the engaging part. We propose a board that is integrally filled with a heat insulating material made of resin foam. [Structure of the invention] An embodiment of the board according to the invention will be described in detail below with reference to the drawings. That is, FIG. 1 is a perspective view showing the board A, where 1 is a surface material;
For example, a metal plate made of one type of surface-treated steel plate, a steel plate plated with a zinc/nickel alloy, an aluminum/zinc alloy plated steel plate (product name: Gulfuan, Galvalume steel plate, Super Zinc), an aluminum plate, an aluminum alloy plate, a copper plate, etc. (including a flat plate and an embossed plate) is formed into the shape shown in FIG. 2 by roll, press, or extrusion molding. That is, the surface material 1 includes a decorative surface 2, a decorative groove 3, a locking portion 4 ,
It is formed from the engaging portion 8 . To explain further, the decorative surface 2 is horizontally elongated, and at least one decorative groove 3 is formed on the surface thereof in parallel to the longitudinal direction. This cosmetic groove 3 is mainly used for the cosmetic surface 2.
In addition to preventing warping, twisting, and flattening of the walls, and making it difficult to distinguish between the horizontal joints and decorative grooves 3 of the wall when constructing Boat A, the wall has a beautiful appearance with one unified pattern. Despite its size, it helps create a three-dimensional effect. To explain further, the decorative groove 3 has a scalene trapezoidal longitudinal section, a so-called vertical bottom surface 3a, a horizontal upper surface 3b which bends the upper edge of the bottom surface 3a outward and is orthogonal to the decorative surface 2, and a decorative groove 3. Lower sloped surface 3 that intersects with surface 2 at an obtuse angle backwards and downwards
It was formed from c. The locking portion 4 is formed by bending the lower end of the decorative surface 2 inward to have a substantially U-shaped longitudinal section. To explain further, the locking part 4 includes a so-called horizontal base 5 that is bent at a substantially right angle to the lower end of the decorative surface 2, a locking piece 6 that is bent with the tip of the bottom side 5 facing upward, and a tip of the locking piece 6. A tongue piece 7 bent outward or inward (not shown) in a seam-like manner.
It was formed from. The bottom side 5 has a length corresponding to the depth of the decorative groove 3, and is formed at right angles to the decorative surface 2 or at an acute angle inward to enhance the three-dimensional effect of the horizontal joints due to shading. . Further, the locking piece 6 makes contact with an engaging portion 8 to be described later over a large area, and also functions as a guide during construction, prevention of edge waving (prevention of deformation), stable support piece, and waterproof surface. Furthermore, the tongue piece 7 forms a gap to prevent capillary phenomenon from occurring at the engagement portion with the protrusion 11 (described later), and prevents the tip of the locking piece 6 from becoming sharp like a knife during construction. This helps eliminate danger during work.
Reference numeral 8 denotes an engaging portion that connects the upper end of the decorative surface 2 with an inclined piece 9 that slopes rearwardly upward at the same angle as the inclined surface 3c of the decorative groove 3, and a joint base portion 10 that extends vertically upward. A rib-shaped protrusion is formed by bending at an acute angle with respect to the surface of the underground portion 10 and folding back again, and a reinforcing spring piece 11a that slopes upward near the lower end of the outer surface of the protrusion 11; It is formed from a nailing piece 12 whose end edge is bent vertically upward, and a tongue piece 13 whose tip end of the nailing piece 12 is bent into a seam shape. To explain further, the inclined piece 9 improves the flow of rainwater, prevents rainwater from accumulating in the side joints, promotes the three-dimensional appearance of the side joints, and is useful for increasing the working width. It is. In addition, the joint base section 10 is made up of a vertical surface or a somewhat inwardly inclined surface, and is a waterproof base for the horizontal joint section.
and serves as a guide for the locking piece 6. The protrusion 11 engages the locking piece 6 under a certain elasticity, and serves to prevent rain and prevent capillary action between the locking piece 6 and the protrusion 11. be. As for the inclination angle of the protrusion 11, it is preferable that only the surface in contact with the tongue piece 7 is inclined in order to strengthen the engagement force. In addition, the reinforcing spring piece 11a expands the driving area of the nail β compared to a case where the outer surface of the protrusion 11 is bent at right angles, and
It is inclined at an angle θ (15 to 45 degrees) to provide elasticity that presses the board A itself toward the substrate. Note that the lower end of the reinforcing spring piece 11a is shaped to protrude from the back surface of the joint basement portion 10. This is because a heat insulating material (described later) is filled between the base (not shown) and the joint base 10 to minimize thermal bridges.
In addition, the nailing piece 12 is mainly fixed to the wall base α through nails β to prevent the occurrence of rust from the nail holes, as shown in FIG. It is useful for Reference numeral 13 denotes a tongue piece which is mainly used to prevent danger during construction and to prevent deformation such as waving at the end of the nailing piece 12. Reference numeral 14 denotes a gutter-like portion, which is surrounded by the decorative surface 2, the locking portion 4 , and the back surface of the engaging portion 8 , and functions as a mold for filling the heat insulating material 15. The insulating material 15 is filled in the gutter-like part 14 and mainly provides insulation to the board A, and secondarily includes a core material, cushion material, reinforcing material, adhesive, soundproofing material, moisture proofing agent, and rust prevention material. It functions as a material. Its shape corresponds to the trough-like portion 14, and a recessed portion 16 of approximately triangular or quadrangular shape (not shown) is provided near the locking portion 4 . The recessed portion 16 is a necessary space when the locking portion 4 is engaged with the engaging portion 8 . The material of the heat insulating material 15 is one type of synthetic resin foam, and may be a material that is discharged as a raw material, molded, hardened, and self-adhesive, or a molded body. In addition, insulation material 1
When a molded body is used as the material 5, it is necessary to use an adhesive (not shown) between the surface material 1 and the back material 17. To explain further, synthetic resin foams include, for example, resins for polyurethane foam, resins for polyisocyanurate foam, resins for phenyl foam, and flame retardants and flame retardant aids (borax, sodium metaborate, calcium carbonate, water, etc.). It consists of one or more of the following: aluminum oxide, antimony trioxide), bentonite, pearlite grains, and shirasu balloons. The back material 17 covers the back surface of the heat insulating material 15,
Mainly, Board A has a sandwich structure, which not only improves the mechanical strength of Board A itself, but also serves as a noncombustible sheet, waterproof membrane, heat shield sheet, water absorption sheet, soundproof sheet, packing material, etc. For example, asbestos Paper, kraft paper, asphalt felt, metal foil (A, Fe, Pb, Cn),
1. Synthetic resin sheets, rubber sheets, cloth sheets, gypsum paper, aluminum hydroxide paper, glass fiber non-woven fabrics, etc.
It is made of seeds, a laminate of two or more kinds, or a sheet that has been treated with waterproofing or flame retardant treatment. [Example of construction] Next, an example of construction will be explained. Assume now that boards A ₁ and A ₂ as shown in FIG. 1 are laid horizontally as shown in FIG. 3 to form an exterior wall. Therefore,
The wall base consists of studs, rims, waterproof sheets, etc. (the figure shows the case where no waterproof sheet is used) α is the nth
The nailing piece 12 of the board _A1 in the tier is fixed via the nail β. Next, the locking part 4 of the (n+1)th stage board A ₂ is engaged with the nth stage engaging part 8 , and the board A ₂
The nailing piece 12 (not shown) is fixed to the wall base α in the same manner as described above. Therefore, in order to construct the entire outer wall, the above-mentioned steps may be performed sequentially from the base side toward the girder. Note that it is necessary to use a starter (not shown) for the base, and caulking material and accessories for vertical joints, exits, and corners of the wall (not shown). [Other Embodiments] What has been described above is only one embodiment of the board A according to the present invention, and includes FIGS. 4 a to e, 5 a to m, 6 a to d, and 7 a. It can also be formed as shown in ~e. That is, FIGS. 4 to 6 show modified examples of each part of the surface material 1 , and FIGS. 4 a to 4 e show the decorative grooves 3.
FIGS. 5 a to 5 m are modified examples of the locking portion 4 , and FIGS. 6 a to 6 d are modified examples of the engaging portion 8 . Note that the thickness of the surface material 1 is omitted in FIGS. 4 to 6. In addition, FIGS. 7a to 7e show the recessed portion 1.
This is another modification of No. 6. In addition, Figures 4 to 7
It is also possible to manufacture a board by combining each of the figures. [Effects of the invention] As mentioned above, according to the board according to the invention,
Capillarity does not occur in the connection structure between the locking part and the engaging part, and the tongue of the locking part and the protrusion of the engaging part prevent rainwater from leaking into the inside of the board. Or, it has the characteristic that it does not corrode the inside of the wall. Additionally, since the board is fixed in a position where rainwater will not leak, there is an advantage in that rust formation and rainwater leakage from nail holes can be prevented. Furthermore, since at least one decorative groove is formed on the decorative surface, the strength is sufficiently reinforced, and the decorative surface does not become mountain-like, making it possible to form a wall body with a beautiful appearance.
Furthermore, when fixing the board to the base, the reinforcing spring piece acts effectively to strengthen the engagement force and prevent the decorative surface from becoming mountain-like. Furthermore, the nail driving area was expanded and the surface material was used more effectively. Furthermore, because the nailing piece is formed to protrude from the back surface of the joint basement, and the gap is filled with a heat insulating material, thermal bridging is minimized.

[Brief explanation of the drawing]

第１図は本考案に係るサイデイングボードの一
実施例を示す斜視図、第２図はその構成材である
表面材を説明する説明図、第３図は上記ボードを
用いて形成した壁体の縦断面の一部を示す説明
図、第４図ａ〜ｅ、第５図ａ〜ｍ、第６図ａ〜
ｄ、第７図ａ〜ｅはその他の実施例を示す説明図
である。Ａ，A₁，A₂……サイデイングボード、３……
化粧溝、４……係止部、８……係合部、１１ａ…
…補強ばね片、１５……断熱材、１７……裏面
材。 Fig. 1 is a perspective view showing an embodiment of the siding board according to the present invention, Fig. 2 is an explanatory view illustrating the surface material constituting the siding board, and Fig. 3 shows a wall formed using the above board. Explanatory drawings showing a part of the longitudinal section, Fig. 4 a-e, Fig. 5 a-m, Fig. 6 a-
d and FIGS. 7a to 7e are explanatory diagrams showing other embodiments. A, A ₁ , A ₂ ... siding board, 3 ...
Decorative groove, 4 ... Locking part, 8 ... Engaging part, 11a...
...Reinforcement spring piece, 15...Insulating material, 17...Back material.

Claims

[Scope of utility model registration request]

The surface material has a concave cross-section made of a horizontally long thin metal plate, a synthetic resin foam filled in the recess of the surface material, and a sheet-like material covering the back side of the foam are integrally constructed, and the surface material is horizontally long. A decorative surface of the decorative surface and at least one decorative groove whose vertical cross section is substantially trapezoidal in shape are formed parallel to the longitudinal direction, and the lower end of the decorative surface is bent inward to form a U-shaped surface. A locking part is provided,
and a sloping piece that slopes rearward upward at the upper end, a joint base part that extends the edge of the slant piece upward almost perpendicularly, and a rib-shaped protrusion that slopes at an acute angle to the surface of the joint base part. The vicinity of the lower edge of the outer side of the protrusion is inclined outward, the tip thereof is extended upward almost vertically, and an engaging portion is formed with a nailing piece formed to protrude from the eye base portion. In addition, the synthetic resin foam is formed parallel to the nailing piece over the back surface of the decorative surface, the joint base area, and the lower end of the decorative surface, and has a triangular shape near the locking part so that it can be engaged with the protrusion. A siding board characterized by a recessed shape or rectangular shape.