Sometimes the results of the glazing calculations seem counter intuitive. For example improving the thermal performance of the glazing (using lower U and SHGC values than required) should, you would think, improve compliance. This is not always the case. In some climate zones (eg Climate Zone 6) the calculator looks for some solar heat gain to reduce heating requirements in winter. This is balanced up with reducing the cooling loads from the solar heat gain in summer. So care must be taken when selecting glazing to ensure it is within a fairly narrow performance band. Application Solutions re-runs the glazing calculations for its clients once the glazing has been selected to prove compliance.