diff --git a/src/libslic3r/Fill/Fill.cpp b/src/libslic3r/Fill/Fill.cpp
index 9d9962dbc8..aecf658a14 100644
--- a/src/libslic3r/Fill/Fill.cpp
+++ b/src/libslic3r/Fill/Fill.cpp
@@ -808,8 +808,10 @@ void split_solid_surface(size_t layer_id, const SurfaceFill &fill, ExPolygons &n
         return;
     }
 
-    // Expand the normal infills a little bit to avoid gaps between normal and narrow infills
-    normal_infill = intersection_ex(offset_ex(normal_fill_areas_ex, scaled_spacing * 0.1), fill.expolygons);
+    // Expand the normal infills to avoid gaps between normal and narrow infills.
+    // The inner_area was shrunk by scaled_spacing * 0.5, so we need to expand
+    // by at least that amount to ensure proper coverage and avoid gaps.
+    normal_infill = intersection_ex(offset_ex(normal_fill_areas_ex, scaled_spacing * 0.5), fill.expolygons);
     narrow_infill = narrow_fill_areas;
 
 #ifdef DEBUG_SURFACE_SPLIT