Wooden building member

Abstract

A wooden building member includes an elongated structural portion having a rectangular cross section and capable of receiving load applied thereto, a coating portion coating an entire length of at least three sides of the cross section of the structural portion, and an insulating portion interposed therebetween in a laminated manner and prevents load from transmitting to the coating portion. Since load is received by the structural portion, structural strength designing is facilitated, and even if the coating portion is completely burned down, the structural portion coated with the insulating portion is not easily burned down. Thus, fireproof capability of the wooden building member can be improved. Further, since a surface of the wooden building member is coated with the coating portion, the insulating portion is not exposed to the exterior thereby improving its appearance.

1 . A wooden building member comprising:
 An elongated structural portion having a rectangular cross-section, and configured to receive a load applied thereto;   a coating portion with which at least three sides of the cross section of the structural portion are coated over an entire length of the structural portion; and   an insulating portion which is interposed between the structural portion and the coating portion in a laminated manner and prevents the load applied to the structural portion from transmitting to the coating portion.   
   
   
       2 . The wooden building member according to  claim 1 , wherein the insulating portion comprises a noncombustible material or an incombustible material. 
   
   
       3 . The wooden building member according to  claim 2 , wherein an aluminum foil is stuck to at least a joint appearing in an outer peripheral surface of the noncombustible material or the incombustible material. 
   
   
       4 . The wooden building member according to  claim 1 , wherein at least one of the structural portion and the coating portion comprises a noncombustible liquid-impregnated building material. 
   
   
       5 . The wooden building member according to  claim 1 , wherein the coating portion has a thickness thereof that is set according to a carbonizing speed of its base material thereby allowing the coat portion not to be burned down in at least an hour. 
   
   
       6 . The wooden building member according to  claim 1 , wherein the coating portion is constituted in such a manner that laminar materials, each having a rectangular cross section are arranged so that one side of the cross section of the laminar material extends approximately perpendicularly to respective sides defining a cross section of the structural portion and their extended lines. 
   
   
       7 . The wooden building member according to  claim 6 , wherein the laminar materials are arranged so that edge grain of each of the laminar materials appears as much as possible on an outer peripheral surface of the coating portion.