diff --git a/conf/config.php b/conf/config.php
index 86b0870..4cc610e 100644
--- a/conf/config.php
+++ b/conf/config.php
@@ -29,6 +29,7 @@
 # show load averages and used memory on overview page
 $CONFIG['showload'] = true;
 $CONFIG['showmem'] = false;
+$CONFIG['showroot'] = false;
 
 $CONFIG['term'] = array(
 	'2hour'	 => 3600 * 2,
diff --git a/inc/html.inc.php b/inc/html.inc.php
index 01e7328..01a5a12 100644
--- a/inc/html.inc.php
+++ b/inc/html.inc.php
@@ -235,13 +235,58 @@ function host_summary($cat, $hosts) {
 			if (isset($rrd_info_mu[$info]) && isset($rrd_info_mf[$info]) && isset($rrd_info_bf[$info]) && isset($rrd_info_ca[$info]) ) {
 				$percent_mem =	$rrd_info_mu[$info] * 100 / ($rrd_info_mu[$info] + $rrd_info_mf[$info] + $rrd_info_bf[$info] + $rrd_info_ca[$info]);
 
-				$class = '';
+				$data_val = '<td>'.(int)$percent_mem.'%</td>';
 				if ($percent_mem > 90)
-					$class = ' class="crit"';
+					$data_val = '<td class="crit"><a href="#" class="tooltip">'.(int)$percent_mem.'%<span><img src="graph.php?p=memory&c=&pi=&t=memory&h='.$host.'"></span></a></td>';
 				elseif ($percent_mem > 70)
-					$class = ' class="warn"';
+					$data_val = '<td class="warn"><a href="#" class="tooltip">'.(int)$percent_mem.'%<span><img src="graph.php?p=memory&c=&pi=&t=memory&h='.$host.'"></span></a></td>';
 
-				printf('<td%s>%d%%</td>', $class, $percent_mem);
+				print($data_val);
+			}
+		}
+
+		if ($CONFIG['showroot']) {
+			if ($CONFIG['version'] == 4) {
+				$rrd_info_df = $rrd->rrd_info($CONFIG['datadir'].'/'.$host.'/df/df-root.rrd');
+
+				# ignore if file does not exist
+				if (!$rrd_info_df)
+					continue;
+
+				if (isset($rrd_info_df["ds[free].last_ds"])) {
+					$total_disk = $rrd_info_df["ds[used].last_ds"] + $rrd_info_df["ds[free].last_ds"];
+					# We assume 5% is allocated only for root because this is the default setting.
+					$percent_disk = ( $rrd_info_df["ds[used].last_ds"] + 5 * $total_disk / 100 ) * 100 / $total_disk;
+
+					$data_val = '<td>'.(int)$percent_disk.'%</td>';
+					if ($percent_disk > 90)
+						$data_val = '<td class="crit"><a href="#" class="tooltip">'.(int)$percent_disk.'%<span><img src="graph.php?p=df&t=df&ti=root&h='.$host.'"></span></a></td>';
+					elseif ($percent_disk > 70)
+						$data_val = '<td class="warn"><a href="#" class="tooltip">'.(int)$percent_disk.'%<span><img src="graph.php?p=df&t=df&ti=root&h='.$host.'"></span></a></td>';
+
+					print($data_val);
+				}
+
+			} elseif ($CONFIG['version'] == 5) {
+				$rrd_info_dff = $rrd->rrd_info($CONFIG['datadir'].'/'.$host.'/df-root/df_complex-free.rrd');
+				$rrd_info_dfu = $rrd->rrd_info($CONFIG['datadir'].'/'.$host.'/df-root/df_complex-reserved.rrd');
+				$rrd_info_dfr = $rrd->rrd_info($CONFIG['datadir'].'/'.$host.'/df-root/df_complex-used.rrd');
+
+				# ignore if file does not exist
+				if (!$rrd_info_dff || !$rrd_info_dfu || !$rrd_info_dfr)
+					continue;
+
+				if (isset($rrd_info_dff["ds[value].last_ds"]) && isset($rrd_info_dfu["ds[value].last_ds"]) && isset($rrd_info_dfr["ds[value].last_ds"])) {
+					$percent_disk = ($rrd_info_dfu["ds[value].last_ds"] + $rrd_info_dfr["ds[value].last_ds"]) * 100 / ($rrd_info_dff["ds[value].last_ds"] + $rrd_info_dfu["ds[value].last_ds"] + $rrd_info_dfr["ds[value].last_ds"]);
+
+					$data_val = '<td>'.(int)$percent_disk.'%</td>';
+					if ($percent_disk > 90)
+						$data_val = '<td class="crit"><a href="#" class="tooltip">'.(int)$percent_disk.'%<span><img src="graph.php?p=df&pi=root&t=df_complex&h='.$host.'"></span></a></td>';
+					elseif ($percent_disk > 70)
+						$data_val = '<td class="warn"><a href="#" class="tooltip">'.(int)$percent_disk.'%<span><img src="graph.php?p=df&pi=root&t=df_complex&h='.$host.'"></span></a></td>';
+
+					print($data_val);
+				}
 			}
 		}
 
diff --git a/layout/style.css b/layout/style.css
index 3d5c94b..3564acd 100644
--- a/layout/style.css
+++ b/layout/style.css
@@ -43,6 +43,35 @@ a:hover {
 	text-decoration: underline;
 }
 
+a.tooltip {
+    border-bottom: dotted 1px blue;
+}
+
+a.tooltip > span {
+    opacity: 0;
+    visibility: hidden; position: absolute;
+    -webkit-transition-property: opacity, visibility;
+    -webkit-transition-duration: 0.4s, 0.4s;
+    -webkit-transition-timing-function: ease-in-out, ease-in-out;
+    -moz-transition-property: opacity, visibility;
+    -moz-transition-duration: 0.4s, 0.4s;
+    -moz-transition-timing-function: ease-in-out, ease-in-out;
+    -o-transition-property: opacity, visibility;
+    -o-transition-duration: 0.4s, 0.4s;
+    -o-transition-timing-function: ease-in-out, ease-in-out;
+    transition-property: opacity, visibility;
+    transition-duration: 0.4s, 0.4s;
+    transition-timing-function: ease-in-out, ease-in-out;
+}
+
+a.tooltip:hover > span {
+    opacity: 1;
+    text-decoration: none;
+    visibility: visible;
+    overflow: visible;
+    display: inline;
+}
+
 table.summary th {
 	width: 300px;
 	font-weight: normal;