Option to upgrade delivery if under certain weight?

We currently have a flat rate for anything over 1KG of £5.99

Anything under that, we will dispatch using Royal Mail.

How can I add the option for anything under 1KG to be upgraded to a courier?

I have tried to edit table.php and added this to line 62:

if ($_SESSION['cart']->TOTAL_WEIGHT < 1) {
$this->enabled = false;
} 

But this makes the shipping page blank.

using it for total_items works fine.

Any ideas?

bump.

Still unable to find a solution to this problem.

bump.

Still unable to find a solution to this problem.

See if using $_SESSION['cart']->weight works for you ...

You should be able to use the code in RED for this:

      // disable only when entire cart is free shipping
      if (zen_get_shipping_enabled($this->code)) {
        $this->enabled = ((MODULE_SHIPPING_FLAT_STATUS == 'True') ? true : false);
      }

      // bof: // disable weight less than 1
      if (!IS_ADMIN_FLAG) {
        if ($_SESSION['cart']->weight < 1) {
          $this->enabled = false;
      }
      // eof: // disable weight less than 1

      if ( ($this->enabled == true) && ((int)MODULE_SHIPPING_FLAT_ZONE > 0) ) {