diff --git a/OpenRA.Mods.Common/Traits/Buildable.cs b/OpenRA.Mods.Common/Traits/Buildable.cs
index 441d706cbd..f8d2fbd58f 100644
--- a/OpenRA.Mods.Common/Traits/Buildable.cs
+++ b/OpenRA.Mods.Common/Traits/Buildable.cs
@@ -41,7 +41,7 @@ namespace OpenRA.Mods.Common.Traits
 		public readonly int BuildDuration = -1;
 
 		[Desc("Percentage modifier to apply to the build duration.")]
-		public readonly int BuildDurationModifier = 150;
+		public readonly int BuildDurationModifier = 60;
 
 		// TODO: UI fluff; doesn't belong here
 		public readonly int BuildPaletteOrder = 9999;
diff --git a/OpenRA.Mods.Common/Traits/Player/ProductionQueue.cs b/OpenRA.Mods.Common/Traits/Player/ProductionQueue.cs
index 81f7d01f20..836289b143 100644
--- a/OpenRA.Mods.Common/Traits/Player/ProductionQueue.cs
+++ b/OpenRA.Mods.Common/Traits/Player/ProductionQueue.cs
@@ -35,7 +35,7 @@ namespace OpenRA.Mods.Common.Traits
 		public readonly bool Sticky = true;
 
 		[Desc("This percentage value is multiplied with actor cost to translate into build time (lower means faster).")]
-		public readonly int BuildSpeed = 40;
+		public readonly int BuildDurationModifier = 100;
 
 		[Desc("The build time is multiplied with this value on low power.")]
 		public readonly int LowPowerSlowdown = 3;
@@ -327,7 +327,7 @@ namespace OpenRA.Mods.Common.Traits
 				time = valued != null ? valued.Cost : 0;
 			}
 
-			time = time * bi.BuildDurationModifier * Info.BuildSpeed / 10000;
+			time = time * bi.BuildDurationModifier * Info.BuildDurationModifier / 10000;
 			return time;
 		}
 
diff --git a/OpenRA.Mods.Common/UtilityCommands/UpgradeRules.cs b/OpenRA.Mods.Common/UtilityCommands/UpgradeRules.cs
index 367b2bf19f..0a54f842b0 100644
--- a/OpenRA.Mods.Common/UtilityCommands/UpgradeRules.cs
+++ b/OpenRA.Mods.Common/UtilityCommands/UpgradeRules.cs
@@ -321,12 +321,21 @@ namespace OpenRA.Mods.Common.UtilityCommands
 							var value = cbtv.Value.Nodes.First(n => n.Key == "Value");
 							value.Key = "BuildDuration";
 							bi.Value.Nodes.Add(value);
-							bi.Value.Nodes.Add(new MiniYamlNode("BuildDurationModifier", "100"));
+							bi.Value.Nodes.Add(new MiniYamlNode("BuildDurationModifier", "40"));
 						}
 
 						node.Value.Nodes.RemoveAll(n => n.Key == "CustomBuildTimeValue");
 						node.Value.Nodes.RemoveAll(n => n.Key == "-CustomBuildTimeValue");
 					}
+
+					// rename ProductionQueue.BuildSpeed
+					if (node.Key == "BuildSpeed")
+					{
+						node.Key = "BuildDurationModifier";
+						var oldValue = FieldLoader.GetValue<int>(node.Key, node.Value.Value);
+						oldValue = oldValue * 100 / 40;
+						node.Value.Value = oldValue.ToString();
+					}
 				}
 
 				UpgradeActorRules(modData, engineVersion, ref node.Value.Nodes, node, depth + 1);