SMARTec™ Durability Doorsets SMARTec™ Durability timber doorsets have been tested to the relevant clauses of DD171 and can be categorised into medium, heavy and severe duty ratings. Visit ASSA ABLOY Opening Solutions Door Group homepage - Severe DutyDescription: Our Severe Duty high performance timber doo… - Heavy DutyDescription: Our Heavy Duty high performance timber doors… - Medium DutyDescription: Our Medium Duty high performance timber door…