diff --git a/heatcalc/heatcalc.js b/heatcalc/heatcalc.js
index cf6e319..a348241 100644
--- a/heatcalc/heatcalc.js
+++ b/heatcalc/heatcalc.js
@@ -188,7 +188,7 @@ function draw_table(){
     // display the table
     $("#table_container").append(table);
 
-    $("#hc_table thead").clone().prependTo("#table_container");
+    $("#hc_table thead").clone().css('postition','fixed').prependTo("#hc_table");
 
     //enable highlighting
     $("#hc_table td").on("mouseover", function() {