PURPOSE: To improve the designing efficiency by holding slidably a sheet containing a chart showing plural inter-beam dimensions, etc., via a cover having display windows in a state where the upper surface side of the sheet is kept hidden.

CONSTITUTION: A slope line limiting chart device contains many display windows 2 formed at the right of a cover 1 to show the inter-beam dimensions 8 as well as display windows 3 under the windows 2 to show the backward distances 7 corresponding to those dimensions 8. The windows 3 correspond to the differences due to a north slope line, a road slope line, the beam sides, the building types, etc., and display the different values. At the same time, the display windows 4 are formed at the upper left of the cover 1 to show the application area names 9 for a 1st class exclusive residential district, etc., together with the display windows 5 showing the propriety of the names 9. Furthermore a sheet 6 contains the dimensions 8, the distances 7, etc. Then the sheet 6 is slidably held by the cover 1 so that the backward distance value caused by the north slope line, for example, is obtained.