Abstract
Size and layout of structural members of Japanese wooden houses are usually decided by a carpenter or builder. But there are few design data and standards available to assist with these decision. The author got their methods of size selection and layout of structural members. Through these surveys, considerations in this paper are as follows : 1. One or two typical sizes are gained every span. 2. At most,it forms 60 or 70 % that the actual size is the same as the typical size. 3. Many opinions are that a round timber is stronger than a square timber for its size. 4. A layout of beam and girder is determined by the upper and under rooms, but a layout of roof is determined by the building outline.
