diff --git a/src/kernel/building.c b/src/kernel/building.c
index f26e153bf..e0dd53908 100644
--- a/src/kernel/building.c
+++ b/src/kernel/building.c
@@ -576,7 +576,7 @@ int bt_effsize(const building_type * btype, const building * b, int bsize)
   const construction *cons = btype->construction;
 
   /* TECH DEBT: simplest thing that works for E3 dwarf/halfling faction rules */
-  if (b && get_param_int(global.parameters, "rules.dwarf_castles", 1)
+  if (b && get_param_int(global.parameters, "rules.dwarf_castles", 0)
     && strcmp(btype->_name, "castle") == 0) {
     unit *u = building_owner(b);
     if (u && u->faction->race == new_race[RC_HALFLING]) {