Résumé
Architects face nowadays the challenge of raising buildings edifices matching functionality of structural design,sustainable raw materials, thrifty energy consumption and aesthetic integration within surrounding environmentinfluenced by human culture and civil engineering heritage considerations. They often specify wood for variousreasons: cost, ecological issues, design versatility, construction facilities, etc. To improve timber structures,material engineers develop innovative wood products allowing to overcome dimensional and mechanical limitsimposed by trees with e.g. longer span capabilities, higher dimensional stability, or higher strength to weightratio.In all these aspects, the question of life expectancy of wood based materials and timber structures is of majorimportance for building safety and one of the major obstacle in people's mind for investment. Wood materialachievements have to be designed with an expected long term viability that englobes several topics such asdetailing construction considerations or even durability issues of termites and fungi resistance as well asaesthetic issues on colour changes in wood due to weathering – but, as a first step, the longevity of woodinherent mechanical performance.