Index: trunk/data/validator/unnecessary.mapcss
===================================================================
--- trunk/data/validator/unnecessary.mapcss	(revision 6778)
+++ trunk/data/validator/unnecessary.mapcss	(revision 6788)
@@ -2,4 +2,5 @@
 *[motor_vehicle?][highway =~ /motorway|trunk|primary|secondary|tertiary|unclassified|residential|service|living_street/],
 *[bridge=no],
+*[building=no],
 *[elevation="0"],
 *[layer="0"] {