diff --git a/src/libslic3r/GCode.cpp b/src/libslic3r/GCode.cpp
index 07af48d86..6d5285883 100644
--- a/src/libslic3r/GCode.cpp
+++ b/src/libslic3r/GCode.cpp
@@ -455,7 +455,7 @@ namespace Slic3r {
                 bool ignore_sparse = false;
                 if (gcodegen.config().wipe_tower_no_sparse_layers.value) {
                     wipe_tower_z = m_last_wipe_tower_print_z;
-                    ignore_sparse = (m_tool_changes[m_layer_idx].size() == 1 && m_tool_changes[m_layer_idx].front().initial_tool == m_tool_changes[m_layer_idx].front().new_tool);
+                    ignore_sparse = (m_tool_changes[m_layer_idx].size() == 1 && m_tool_changes[m_layer_idx].front().initial_tool == m_tool_changes[m_layer_idx].front().new_tool && m_layer_idx != 0);
                     if (m_tool_change_idx == 0 && !ignore_sparse)
                         wipe_tower_z = m_last_wipe_tower_print_z + m_tool_changes[m_layer_idx].front().layer_height;
                 }
diff --git a/src/libslic3r/GCode/WipeTower.cpp b/src/libslic3r/GCode/WipeTower.cpp
index 577ce9e34..33d3960d8 100644
--- a/src/libslic3r/GCode/WipeTower.cpp
+++ b/src/libslic3r/GCode/WipeTower.cpp
@@ -1180,7 +1180,7 @@ WipeTower::ToolChangeResult WipeTower::finish_layer()
 
     // Ask our writer about how much material was consumed.
     // Skip this in case the layer is sparse and config option to not print sparse layers is enabled.
-    if (! m_no_sparse_layers || toolchanges_on_layer)
+    if (! m_no_sparse_layers || toolchanges_on_layer || first_layer)
         if (m_current_tool < m_used_filament_length.size())
             m_used_filament_length[m_current_tool] += writer.get_and_reset_used_filament_length();
 
@@ -1196,7 +1196,7 @@ void WipeTower::plan_toolchange(float z_par, float layer_height_par, unsigned in
 	if (m_plan.empty() || m_plan.back().z + WT_EPSILON < z_par) // if we moved to a new layer, we'll add it to m_plan first
 		m_plan.push_back(WipeTowerInfo(z_par, layer_height_par));
 
-    if (m_first_layer_idx == size_t(-1) && (! m_no_sparse_layers || old_tool != new_tool))
+    if (m_first_layer_idx == size_t(-1) && (! m_no_sparse_layers || old_tool != new_tool || m_plan.size() == 1))
         m_first_layer_idx = m_plan.size() - 1;
 
     if (old_tool == new_tool)	// new layer without toolchanges - we are done