function change_nieuwbouw(element){
	var element1 = document.forms[0].ligging1
	var element2 = document.forms[0].ligging2
	var element3 = document.forms[0].ligging3
		element1.disabled =element.checked;
		element1.readOnly = element.checked;
		element2.disabled =element.checked;
		element2.readOnly = element.checked;
		element3.disabled =element.checked;
		element3.readOnly = element.checked;
		if(element.checked){
			element1.checked= true;	
			element2.checked= true;	
			element3.checked= true;	
		}
else {
			element1.checked= false;
			element2.checked= false;
			element3.checked= false;
		}
	return true;
}