function updateArea()
{
	roomWidth = document.form1.roomWidth.selectedIndex;
	roomLength = document.form1.roomLength.selectedIndex;
         curRows = document.getElementById('areaTable').rows.length;

         floorArea = roomWidth * roomLength;
	
         //alert("cur rows: " + curRows + " width: " + roomWidth + " length: " + roomLength + " area: " + floorArea );

	doRow=curRows;

         if(curRows==5)
	{
              if(floorArea>0)
              {
                  //add row1
                  var x = document.getElementById('areaTable').insertRow(doRow);
                  var a = x.insertCell(0);
                  a.innerHTML="<center><span class='middle-normal-text'><b>Your Floor Area is:</b></span></center>";

                  doRow++;

                  //add row2
                  var y = document.getElementById('areaTable').insertRow(doRow);
                  var b = y.insertCell(0);
                  b.innerHTML="<center><span class='middle-normal-text'><b><span id='areaText'>" + floorArea + "</span>&nbsp;square metres/feet</b></span></center>";
              }
	}
	else if(curRows==7)
	{
              document.getElementById('areaText').innerHTML = floorArea;

              if(floorArea==0)
              {
                  while(doRows!=5)
                  {                  
                       //delete rows
                       var x = document.getElementById('areaTable');
                       x.deleteRows(doRow-1);
                       doRow--;
                  }
              }
              else
              {
                  document.getElementById('areaText').innerHTML = floorArea;
              }
	}
}