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Insulated garage doors will obviously give you a warmer garage if they are installed and specified correctly in the first place.
By their very nature insulated doors are always twin walled in construction and therefore also offer higher levels of panel strength whether in steel or aluminium. It is quite often the strength of the door panels which is more important and the insulation is a bonus. Panel strength also equates to higher security against attempted forced entry.
The highest levels of insulation come from the sectional type garage doors and the insulated roller doors generally do not have a specified 'U' value for insulation levels as they have too many areas where draughts and gaps are present. The best way to make sure an insulated roller door at least gives you a good level of insulation is to order the widest guides and a full hood cover to reduce the levels of air entering the garage. Some sectional garage door maufacturers now offer an upgrade on the standard frame mechanism to give even better levels of insulation for garages where it is important, i.e. rooms above, integral garage with rooms to the sides and back or where a lot of people nowadays are using the garage for a workshop, gym, office, playroom or other purpose.
Hormann offer the LPU42 as their insulated sectional door models and is 42mm thick. Carteck have recently introduced a range of stylish insulated side hinged garage doors, all made to measure with high quality hinges, locking and weatherseals and we think these offer excellent value for money for the specification. They are delivered with everything factory fitted including a fixing steel sub frame and for long term stability are head and shoulders above other types of side hinged doors.