diff --git a/include/qbsp/brushbsp.hh b/include/qbsp/brushbsp.hh
index d62ecd26..5ba15cc6 100644
--- a/include/qbsp/brushbsp.hh
+++ b/include/qbsp/brushbsp.hh
@@ -98,6 +98,7 @@ enum tree_split_t
     FAST
 };
 
+vec_t BrushVolume(const bspbrush_t &brush);
 bspbrush_t::ptr BrushFromBounds(const aabb3d &bounds);
 void BrushBSP(tree_t &tree, mapentity_t &entity, const bspbrush_t::container &brushes, tree_split_t split_type);
 void ChopBrushes(bspbrush_t::container &brushes, bool allow_fragmentation);
\ No newline at end of file
diff --git a/include/qbsp/qbsp.hh b/include/qbsp/qbsp.hh
index 4d2608c9..ebef3dfa 100644
--- a/include/qbsp/qbsp.hh
+++ b/include/qbsp/qbsp.hh
@@ -366,6 +366,8 @@ public:
     setting_bool debugleak{this, "debugleak", false, &debugging_group, "write more diagnostic files for debugging leaks"};
     setting_bool debugbspbrushes{
         this, "debugbspbrushes", false, &debugging_group, "save bsp brushes after BrushBSP to a .map, for visualizing BSP splits"};
+    setting_bool debugleafvolumes{this, "debugleafvolumes", false, &debugging_group,
+        "save bsp leaf volumes after BrushBSP to a .map, for visualizing BSP splits"};
     setting_debugexpand debugexpand{this, "debugexpand", &debugging_group, "write expanded hull .map for debugging/inspecting hulls/brush bevelling"};
     setting_bool keepprt{this, "keepprt", false, &debugging_group, "avoid deleting the .prt file on leaking maps"};
     setting_bool includeskip{this, "includeskip", false, &common_format_group,
diff --git a/qbsp/brushbsp.cc b/qbsp/brushbsp.cc
index 44f05337..1ce7aafc 100644
--- a/qbsp/brushbsp.cc
+++ b/qbsp/brushbsp.cc
@@ -152,6 +152,11 @@ static vec_t BrushVolume(T begin, T end)
     return volume;
 }
 
+vec_t BrushVolume(const bspbrush_t &brush)
+{
+    return BrushVolume(brush.sides.begin(), brush.sides.end());
+}
+
 //========================================================
 
 /*
@@ -554,7 +559,7 @@ static twosided<bspbrush_t::ptr> SplitBrush(bspbrush_t::ptr brush, size_t planen
     }
 
     for (int i = 0; i < 2; i++) {
-        vec_t v1 = BrushVolume(result[i]->sides.begin(), result[i]->sides.end());
+        vec_t v1 = BrushVolume(*result[i]);
         if (v1 < qbsp_options.microvolume.value()) {
             result[i] = nullptr;
             if (stats) {
diff --git a/qbsp/qbsp.cc b/qbsp/qbsp.cc
index 2202792c..510662ef 100644
--- a/qbsp/qbsp.cc
+++ b/qbsp/qbsp.cc
@@ -402,6 +402,17 @@ static void GatherBspbrushes_r(node_t *node, bspbrush_t::container &container)
     GatherBspbrushes_r(node->children[1], container);
 }
 
+static void GatherLeafVolumes_r(node_t *node, bspbrush_t::container &container)
+{
+    if (node->is_leaf) {
+        container.push_back(node->volume);
+        return;
+    }
+
+    GatherLeafVolumes_r(node->children[0], container);
+    GatherLeafVolumes_r(node->children[1], container);
+}
+
 /*
 ===============
 ProcessEntity
@@ -529,10 +540,17 @@ static void ProcessEntity(mapentity_t &entity, hull_index_t hullnum)
 
     if (map.is_world_entity(entity)) {
         // debug output of bspbrushes
-        if (qbsp_options.debugbspbrushes.value() && (!hullnum.has_value() || hullnum.value() == 0)) {
-            bspbrush_t::container all_bspbrushes;
-            GatherBspbrushes_r(tree.headnode, all_bspbrushes);
-            WriteBspBrushMap("first-brushbsp", all_bspbrushes);
+        if (!hullnum.has_value() || hullnum.value() == 0) {
+            if (qbsp_options.debugbspbrushes.value()) {
+                bspbrush_t::container all_bspbrushes;
+                GatherBspbrushes_r(tree.headnode, all_bspbrushes);
+                WriteBspBrushMap("first-brushbsp", all_bspbrushes);
+            }
+            if (qbsp_options.debugleafvolumes.value()) {
+                bspbrush_t::container all_bspbrushes;
+                GatherLeafVolumes_r(tree.headnode, all_bspbrushes);
+                WriteBspBrushMap("first-brushbsp-volumes", all_bspbrushes);
+            }
         }
 
         // flood fills from the void.
@@ -545,10 +563,17 @@ static void ProcessEntity(mapentity_t &entity, hull_index_t hullnum)
             BrushBSP(tree, entity, brushes, tree_split_t::PRECISE);
 
             // debug output of bspbrushes
-            if (qbsp_options.debugbspbrushes.value() && (!hullnum.has_value() || hullnum.value() == 0)) {
-                bspbrush_t::container all_bspbrushes;
-                GatherBspbrushes_r(tree.headnode, all_bspbrushes);
-                WriteBspBrushMap("second-brushbsp", all_bspbrushes);
+            if (!hullnum.has_value() || hullnum.value() == 0) {
+                if (qbsp_options.debugbspbrushes.value()) {
+                    bspbrush_t::container all_bspbrushes;
+                    GatherBspbrushes_r(tree.headnode, all_bspbrushes);
+                    WriteBspBrushMap("second-brushbsp", all_bspbrushes);
+                }
+                if (qbsp_options.debugleafvolumes.value()) {
+                    bspbrush_t::container all_bspbrushes;
+                    GatherLeafVolumes_r(tree.headnode, all_bspbrushes);
+                    WriteBspBrushMap("second-brushbsp-volumes", all_bspbrushes);
+                }
             }
 
             // make the real portals for vis tracing