diff --git a/src/Element/GridStart.php b/src/Element/GridStart.php
index 0c2f687..527e963 100644
--- a/src/Element/GridStart.php
+++ b/src/Element/GridStart.php
@@ -98,9 +98,9 @@ protected function getResponse(Template $template, ContentModel $model, Request
             $template->gridClasses .= ' '.$model->cp_grid_halign;
         }
 
-        $template->gridClasses .= $this->generateGapClass('mobile', $model->cp_gap_mobile);
-        $template->gridClasses .= $this->generateGapClass('tablet', $model->cp_gap_tablet);
-        $template->gridClasses .= $this->generateGapClass('desktop', $model->cp_gap_desktop);
+        $template->gridClasses .= ($model->cp_gap_mobile)  ? $this->generateGapClass('mobile', $model->cp_gap_mobile) : '';
+        $template->gridClasses .= ($model->cp_gap_tablet) ? $this->generateGapClass('tablet', $model->cp_gap_tablet) : '';
+        $template->gridClasses .= ($model->cp_gap_desktop) ? $this->generateGapClass('desktop', $model->cp_gap_desktop) : '';
 
         return $template->getResponse();
     }
@@ -121,21 +121,21 @@ private function getConfigInfo(ContentModel $model): string
             '%s: %s %s, ',
             $GLOBALS['TL_LANG']['tl_content']['cp_grid_mobile'][0],
             $GLOBALS['TL_LANG']['tl_content']['cp_grid_options'][$model->cp_grid_mobile],
-            $this->formatGapOption($model->cp_gap_mobile)
+            isset($model->cp_gap_mobile) ? $this->formatGapOption($model->cp_gap_mobile) : ''
         );
 
         $configInfo .= \sprintf(
             '%s: %s %s, ',
             $GLOBALS['TL_LANG']['tl_content']['cp_grid_tablet'][0],
             $GLOBALS['TL_LANG']['tl_content']['cp_grid_options'][$model->cp_grid_tablet],
-            $this->formatGapOption($model->cp_gap_tablet)
+            isset($model->cp_gap_tablet) ? $this->formatGapOption($model->cp_gap_tablet) : ''
         );
 
         $configInfo .= \sprintf(
             '%s: %s %s, ',
             $GLOBALS['TL_LANG']['tl_content']['cp_grid_desktop'][0],
             $GLOBALS['TL_LANG']['tl_content']['cp_grid_options'][$model->cp_grid_desktop],
-            $this->formatGapOption($model->cp_gap_desktop)
+            isset($model->cp_gap_desktop) ? $this->formatGapOption($model->cp_gap_desktop) : ''
         );
 
         $configInfo .= '</span>';