Merbau is the hardwood species from South East Asia( paricularly from Indonesia). In the market of China,Merbau is regarded as one of the best quality weathering hardwood for outdoor construction & terrace outdoor wood decking & cladding wood species .
 
It is a fact that a cladding has to stand the pressure of the outside climate. So, if you do not opt for a durable material for cladding , then you need to repurchase materials which will cost you a lot of Money. So, if you are looking for a durable material, try using merbau that is known for its toughness and durability.