diff --git a/include/light/light.hh b/include/light/light.hh
index 7bf81cf9..041e5375 100644
--- a/include/light/light.hh
+++ b/include/light/light.hh
@@ -392,6 +392,7 @@ public:
     setting_bool lightgrid;
     setting_vec3 lightgrid_dist;
     setting_bool lightgrid_force_cube;
+    setting_bool lightgrid_force_pot;
     setting_enum<lightgrid_format_t> lightgrid_format;
 
     setting_func dirtdebug;
diff --git a/light/light.cc b/light/light.cc
index a03a8d2b..a6f2e9b1 100644
--- a/light/light.cc
+++ b/light/light.cc
@@ -317,6 +317,7 @@ light_settings::light_settings()
       lightgrid{this, "lightgrid", false, &experimental_group, "experimental LIGHTGRID bspx lump"},
       lightgrid_dist{this, "lightgrid_dist", 32.f, 32.f, 32.f, &experimental_group, "distance between lightgrid sample points, in world units. controls lightgrid size."},
       lightgrid_force_cube{this, "lightgrid_force_cube", false, &experimental_group, "force lightgrid to be a cube"},
+      lightgrid_force_pot{this, "lightgrid_force_pot", false, &experimental_group, "force lightgrid to be a power of 2"},
       lightgrid_format{this, "lightgrid_format", lightgrid_format_t::OCTREE,
         {{"cluster", lightgrid_format_t::CLUSTER}, {"uniform", lightgrid_format_t::UNIFORM}, {"octree", lightgrid_format_t::OCTREE}}, &experimental_group, "lightgrid BSPX lump to use"},
 
diff --git a/light/lightgrid.cc b/light/lightgrid.cc
index 5618215c..11c67172 100644
--- a/light/lightgrid.cc
+++ b/light/lightgrid.cc
@@ -501,6 +501,15 @@ static aabb3f MakeCube(const aabb3f &input)
         centroid + qvec3f(new_size / 2));
 }
 
+static qvec3i MakePOT(const qvec3i& input)
+{
+    float x = static_cast<float>(input[0]);
+    x = log2(x);
+    x = ceil(x);
+    x = exp2(x);
+    return qvec3i(static_cast<int>(x));
+}
+
 void LightGrid(bspdata_t *bspdata)
 {
     if (!light_options.lightgrid.value())
@@ -531,6 +540,26 @@ void LightGrid(bspdata_t *bspdata)
         ceil(world_size[2] / data.grid_dist[2])
     };
 
+    if (light_options.lightgrid_force_pot.value()) {
+        const auto old_grid_size = data.grid_size;
+
+        logging::print("before making power of 2: data.grid_size: {}\n", data.grid_size);
+        data.grid_size = MakePOT(data.grid_size);
+        logging::print("after: data.grid_size: {}\n", data.grid_size);
+
+        // adjust the grid mins to preserve the old center point
+
+        qvec3f old_maxs = data.grid_mins + (old_grid_size * data.grid_dist);
+        // should always be >= old_maxs on each component
+        qvec3f new_maxs = data.grid_mins + (data.grid_size * data.grid_dist);
+
+        qvec3f delta = (new_maxs - old_maxs) / 2;
+
+        logging::print("shifting by -{}\n", delta);
+
+        data.grid_mins -= delta;
+    }
+
     data.grid_result.resize(data.grid_size[0] * data.grid_size[1] * data.grid_size[2]);
 
     data.occlusion.resize(data.grid_size[0] * data.grid_size[1] * data.grid_size[2]);