23 6 



CORRUGATED 



Span of roof, 

 up to 50' 

 50' to 70' 

 70' to 100' 



Gutter. 

 6" 



7" 

 8" 



Conductor. 

 \" every 40' 

 ," " 40' 

 ;" " 40' 



Hanging gutters should have a slope of at least I inch to 15 feet. 

 The diagram in Fig. 118 for the design of gutters and conductors 

 was described in Engineering News, April 17, 1902, by Mr. Emmett 

 Steece, Assoc. M. A. Soc. C. E., City Engineer of Burlington, Iowa, as 

 follows : 



s'S 



Plan, Square Feet. 



FIG. 118. 



Encj.New* 



"The curves are for y^ pitch or flat roofs, to full pitch or domes. 

 The areas are reduced to plan as shown. The minimum sizes of circu- 

 lar and commercial rectangular conductors are given on the left side 

 of the diagram and the sizes and the minimum cross-sectional areas of 

 square gutters are given on the right hand side. 



To use the diagram : Assume an area of roof, say 30 x 100 ft., or 

 3000 sq. ft., y 2 pitch and one conductor for the whole area. Note the 

 intersection of the vertical over area 3000 and the curve of ^2 pitch; 

 following thence the horizontal line to the left it strikes a diameter of 5 

 ins. for circular, or over 3% x 4$% ins. for commercial size. The next 

 larger size would be used. The minimum cross-sectional area of gut- 

 ters is shown on the right to be about 30 sq. ins., and the side of a 

 square conductor about 4.5 ins." 



This diagram was based on a maximum rainfall of 1.98 inches 

 per hour. 



