Index: binaries/data/mods/public/simulation/components/Builder.js
===================================================================
--- binaries/data/mods/public/simulation/components/Builder.js
+++ binaries/data/mods/public/simulation/components/Builder.js
@@ -11,6 +11,9 @@
 	"<element name='Rate' a:help='Construction speed multiplier (1.0 is normal speed, higher values are faster).'>" +
 		"<ref name='positiveDecimal'/>" +
 	"</element>" +
+	"<element name='AutoBuildRange' a:help='Max distance to search for a new foundation to construct.'>" +
+		"<ref name='positiveDecimal'/>" +
+	"</element>" +
 	"<element name='Entities' a:help='Space-separated list of entity template names that this unit can build. The special string \"{civ}\" will be automatically replaced by the civ code of the unit&apos;s owner, while the string \"{native}\" will be automatically replaced by the unit&apos;s civ code. This element can also be empty, in which case no new foundations may be placed by the unit, but they can still repair existing buildings.'>" +
 		"<attribute name='datatype'>" +
 			"<value>tokens</value>" +
@@ -57,6 +60,11 @@
 	return { "max": max, "min": 0 };
 };
 
+Builder.prototype.GetAutoBuildRange = function()
+{
+	return ApplyValueModificationsToEntity("Builder/AutoBuildRange", +this.template.AutoBuildRange, this.entity);
+};
+
 Builder.prototype.GetRate = function()
 {
 	return ApplyValueModificationsToEntity("Builder/Rate", +this.template.Rate, this.entity);
Index: binaries/data/mods/public/simulation/components/ResourceGatherer.js
===================================================================
--- binaries/data/mods/public/simulation/components/ResourceGatherer.js
+++ binaries/data/mods/public/simulation/components/ResourceGatherer.js
@@ -21,6 +21,9 @@
 	"<element name='MaxDistance' a:help='Max resource-gathering distance'>" +
 		"<ref name='positiveDecimal'/>" +
 	"</element>" +
+	"<element name='AutoGatherRange' a:help='Max distance to search for a new resource to gather.'>" +
+		"<ref name='positiveDecimal'/>" +
+	"</element>" +
 	"<element name='BaseSpeed' a:help='Base resource-gathering rate (in resource units per second)'>" +
 		"<ref name='positiveDecimal'/>" +
 	"</element>" +
@@ -149,6 +152,11 @@
 	// maybe this should depend on the unit or target or something?
 };
 
+ResourceGatherer.prototype.GetAutoGatherRange = function()
+{
+	return ApplyValueModificationsToEntity("ResourceGatherer/AutoGatherRange", +this.template.AutoGatherRange, this.entity);
+};
+
 /**
  * Try to gather treasure
  * @return 'true' if treasure is successfully gathered, otherwise 'false'
Index: binaries/data/mods/public/simulation/components/UnitAI.js
===================================================================
--- binaries/data/mods/public/simulation/components/UnitAI.js
+++ binaries/data/mods/public/simulation/components/UnitAI.js
@@ -4160,10 +4160,13 @@
 		return undefined;
 	let owner = cmpOwnership.GetOwner();
 
-	// We accept resources owned by Gaia or any player
+	// We accept resources owned by any player (including Gaia).
 	let players = Engine.QueryInterface(SYSTEM_ENTITY, IID_PlayerManager).GetAllPlayers();
 
-	let range = 64; // TODO: what's a sensible number?
+	let cmpResourceGatherer = Engine.QueryInterface(this.entity, IID_ResourceGatherer);
+	if (!cmpResourceGatherer)
+		return undefined;
+	let range = cmpResourceGatherer.GetAutoGatherRange();
 
 	let cmpTemplateManager = Engine.QueryInterface(SYSTEM_ENTITY, IID_TemplateManager);
 	let cmpRangeManager = Engine.QueryInterface(SYSTEM_ENTITY, IID_RangeManager);
@@ -4254,17 +4257,20 @@
  */
 UnitAI.prototype.FindNearbyFoundation = function()
 {
-	var cmpOwnership = Engine.QueryInterface(this.entity, IID_Ownership);
+	let cmpOwnership = Engine.QueryInterface(this.entity, IID_Ownership);
 	if (!cmpOwnership || cmpOwnership.GetOwner() == INVALID_PLAYER)
 		return undefined;
 
-	// Find buildings owned by this unit's player
-	var players = [cmpOwnership.GetOwner()];
+	let players = [cmpOwnership.GetOwner()];
 
-	var range = 64; // TODO: what's a sensible number?
+	let cmpBuilder = Engine.QueryInterface(this.entity, IID_Builder);
+	if (!cmpBuilder)
+		return undefined;
 
-	var cmpRangeManager = Engine.QueryInterface(SYSTEM_ENTITY, IID_RangeManager);
-	var nearby = cmpRangeManager.ExecuteQuery(this.entity, 0, range, players, IID_Foundation);
+	let range = cmpBuilder.GetAutoBuildRange();
+
+	let cmpRangeManager = Engine.QueryInterface(SYSTEM_ENTITY, IID_RangeManager);
+	let nearby = cmpRangeManager.ExecuteQuery(this.entity, 0, range, players, IID_Foundation);
 
 	// Skip foundations that are already complete. (This matters since
 	// we process the ConstructionFinished message before the foundation
Index: binaries/data/mods/public/simulation/templates/template_unit.xml
===================================================================
--- binaries/data/mods/public/simulation/templates/template_unit.xml
+++ binaries/data/mods/public/simulation/templates/template_unit.xml
@@ -82,6 +82,7 @@
   <RangeOverlayRenderer/>
   <ResourceGatherer>
     <MaxDistance>2.0</MaxDistance>
+    <AutoGatherRange>64</AutoGatherRange>
     <BaseSpeed>1.0</BaseSpeed>
     <Rates>
       <treasure>1</treasure>
Index: binaries/data/mods/public/simulation/templates/template_unit_infantry.xml
===================================================================
--- binaries/data/mods/public/simulation/templates/template_unit_infantry.xml
+++ binaries/data/mods/public/simulation/templates/template_unit_infantry.xml
@@ -23,6 +23,7 @@
   </Attack>
   <Builder>
     <Rate>1.0</Rate>
+    <AutoBuildRange>64</AutoBuildRange>
     <Entities datatype="tokens">
       structures/{civ}_house
       structures/{civ}_storehouse
Index: binaries/data/mods/public/simulation/templates/template_unit_support_female_citizen.xml
===================================================================
--- binaries/data/mods/public/simulation/templates/template_unit_support_female_citizen.xml
+++ binaries/data/mods/public/simulation/templates/template_unit_support_female_citizen.xml
@@ -25,6 +25,7 @@
   </Auras>
   <Builder>
     <Rate>1.0</Rate>
+    <AutoBuildRange>64</AutoBuildRange>
     <Entities datatype="tokens">
       structures/{civ}_house
       structures/{civ}_storehouse
Index: binaries/data/mods/public/simulation/templates/template_unit_support_slave.xml
===================================================================
--- binaries/data/mods/public/simulation/templates/template_unit_support_slave.xml
+++ binaries/data/mods/public/simulation/templates/template_unit_support_slave.xml
@@ -2,6 +2,7 @@
 <Entity parent="template_unit_support">
   <Builder>
     <Rate>0.5</Rate>
+    <AutoBuildRange>64</AutoBuildRange>
     <Entities datatype="tokens">
       structures/{civ}_house
       structures/{civ}_storehouse
Index: binaries/data/mods/public/simulation/templates/units/maur_support_elephant.xml
===================================================================
--- binaries/data/mods/public/simulation/templates/units/maur_support_elephant.xml
+++ binaries/data/mods/public/simulation/templates/units/maur_support_elephant.xml
@@ -7,6 +7,7 @@
   </Armour>
   <Builder>
     <Rate>2.0</Rate>
+    <AutoBuildRange>64</AutoBuildRange>
     <Entities datatype="tokens"/>
   </Builder>
   <Cost>