PROBLEM TO BE SOLVED: To provide a construction method that is capable of increasing the light transmittance of the entire double translucent films used for an agricultural house.SOLUTION: According to the present invention, an east-west ridge whose roof ridge direction is roughly in the east-west direction comprises double translucent films or double translucent plates, which form an air heat-insulating layer, at least one translucent film or translucent plate on the inside surface or outside surface being provided as a light-diffusing translucent film 4, 5 or light-diffusing translucent plate.SELECTED DRAWING: Figure 3【課題】農業用ハウスに用いられる二重透光フィルム全体の光透過率を高めることができる施工方法を提供する。【解決手段】空気断熱層を形成する二重の透光フィルムまたは二重の透光板を有し、透光フィルムまたは透光板のうち、少なくともハウス内側面及びハウス外側面のいずれか一方の透光フィルムまたは透光板を、光が拡散する光拡散透光フィルム４、５または光拡散透光板とし、屋根の稜線方向を概ね東西方向とした東西棟として施工する。【選択図】図３
