Ceiling Insulation Penetrations

When a Star Rating has been done it may still require more insulation than that nominated in the Rating. This is because of the new requirement to compensate for the loss of insulation due to such things as down lights & exhaust fans.
To avoid having to increase the ceiling insulation minimise the diameter of of these items and try to keep down lights to a minimum (say 16) or be prepared to add extra ceiling insulation.