TILED ROOFS FOR MODERN BUILDINGS


   A number of years ago an effort was made by a French publica-
tion to arrive at a rule for the pitch of roofs based upon climatic
conditions. The globe between the equator and the polar circle was
divided into twenty-four belts or bands parallel to the equator, but
of unequal size, depending upon the length of the longest day. Allow-
ances were made for dryer and damper climates, and for the shape
of the tiles; "in the roofs of the continent covered with the hollow
tile (like Mission tile), as in the south of France, for instance, less
slope is required than with the Roman tiles which are in sections
alternately flat and circular, and -these again require less slope than
the common plain tile or slate." A table constructed in accordance
with the theory gives the following variations in pitch for the coun-
tries, localities and materials named
  LOCALITY                     HOLLOW TILES       PLAIN TILES
Southern Spain-pitch ......... 16 deg. 12 min.   24 deg. 12 min.
         Italy ................ 18     12  "     26  "   12  "
         France .............. 21  "             29
Northern    ".  ............. 24   "   36   "    32  "
  36  "
   "      Germany ............ 28  "   36  "     36  "
  36   "
England (London) ............ 27   "   24  "     35  "   
4"
Scotland ..................... 33      12  "     4   "   12  "
Sweden, Russia and Norway
     (average) ................. 30 "49
According to above table South-
    ern California would require
    about .................... 17                i 26
    In pitch, the Mission roofs varied greatly. The variations are
as numerous as the structures themselves. No rule of construction
can be laid down which would not be compelled to admit brilliant
and successful exceptions. The good builder is not restricted by
arbitrary considerations, he meets conditions as he finds them and
builds as he pleases; if he consider only the needs of the people and
the exigencies of environment, and if he uses only the materials of
the vicinity, he cannot go far astray.


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