326 PARKS 



the cost will vary considerably in different localities, due to the soil con- 

 ditions and price of labor and materials. Once constructed, these courts 

 present a minimum of maintenance, especially where they are subjected 

 to constant playing. 



The following statement concerning the probable cost of constructing 

 an asphalt tennis court was made in October 1926 by Mr. Walter E. Rosen- 

 garten, traffic engineer of the Asphalt Association. It should be kept in 

 mind, however, that this figure does not include the cost of excavating 

 where this is necessary or of erecting the backstops. 



"In order to give simply a rough idea I would estimate that the mixed 

 types of asphalt surfaces on well prepared foundations for a paved area of 

 60 x 120 feet might be in the neighborhood of #1,500; for the penetration 

 type of construction about #800, and for the gravel surface treated about 

 #500. If anyone is considering constructing an asphalt tennis court, I 

 would strongly recommend that he discuss the matter with a local asphalt 

 paving contractor who would give a much more reliable estimate. If he is 

 unable to locate an asphalt paving contractor it is quite likely that the city 

 engineer could either give him the information or direct them to a contractor." 1 



The following are specifications of the Park Department at Pasadena, 

 California, for a 60 x 120-foot asphalt tennis court: 



Subgrade. The subgrade should be excavated preferably to a grade of 

 .30 foot fall from the center to each end of the court, or almost equally as 

 good the fall may be .60 from one end to the other end. The surface should 

 be brought to as near a perfect plane as is possible. 



Sub-base. A layer one inch thick of No. 4 crushed rock should then be 

 placed upon the subgrade and thoroughly rolled, then thoroughly oiled with 

 60 gravity oil. Upon the No. 4 crushed rock should be placed a layer of pea 

 gravel to cover the oil completely, and the pea gravel in turn thoroughly 

 rolled and oiled. 



Surface finish. Fine sand or crushed stone dust should be placed upon 

 the surface, thoroughly rolled to absorb any excess oil and the surplus 

 removed, at which time the court is ready for service. 



Asphalt courts in Detroit. Among the cities making extensive use of 

 asphalt courts is Detroit, Michigan, and the following are the specifications 

 used by the Department of Recreation in that city: 



Excavate eight inches, and if subsoil needs draining, four inches of 

 agricultural tile should be laid. On top of this, five inches of crushed lime- 

 stone or granite two inches in size should be uniformly spread, thoroughly 

 wet and rolled with a steam roller. On top of this enough limestone screen- 

 ings ranging in size from dust to three-fourths of an inch should be spread over 

 the surface and broomed into the voids until all voids are filled to within 

 one-half inch of the top of grade. Excess screenings should be swept from 



1 The Asphalt Association, 441 Lexington Avenue, New York City, has issued a bulletin entitled "Proper 

 Methods in Constructing Asphalt Tennis Courts," containing specifications for materials and detailed directions 

 for constructing a court. 



