To provide glued laminated bamboo material which is easily deflected and corrected during installing it even when it is warped back and displays heat insulating and soundproofing effects due to a still air layer existing in a slotted strip by forming long slotted strips side by side on the second surface of a platelike laminated material obtained by shred ding bamboos longitudinally and bonding the slender bamboo materials with a widthwise long rectangular cross section in parallel.

Slender bamboo materials 1 with a widthwise long rectangular cross section which are obtained by shredding bamboos longitudinally are bonded together side by side to form a platelike laminated bamboo material 2 having long slotted strips 3 formed side by side at a specified interval on the second surface of the material 2. In order to make almost uniform a warp caused by a year-long time change in the quality of the laminated bamboo material 2 or its forward/backward bending strength, the first and the second surface of the mutually adjacent bamboo materials 1 are reversed and the upper and the lower part thereof are reversed and bonded together side by side as the upper part of the bamboo is narrow and this-walled. The laminated bamboo material 2 is easily deflected on account of the slotted strips 3 formed on the second surface of the material 2. The laminate of the bamboo materials 2 is tensely installed on the foundation surface of a floor or a wall to form a floor or a wall surface. Consequently, it is possible to easily correct a warp during installing and upgrade heat insulating or soundproofing effects by a still air layer in the slotted strips 3 after the laminated is tensely installed on the floor or the wall material.