Shareholders of Vancouver-based West Fraser Timber and Toronto-based Norbord have voted to join forces.
The move unites two of Canada's largest producers of wood products, creating a single Vancouver-based firm which keeps the West Fraser name.
It now boasts 10,000 employees.
Officials behind the merger say the new company, which will be owned 56% by West Fraser shareholders and 44% by Norbord investors, aims to be a "one-stop shop" for construction customers.
West Fraser has 45 mills and other facilities across BC, Alberta, and the southern US, while Norbord has an oriented strand board mill in 100 Mile House and operations in Alberta, Ontario, Quebec and several southeastern US states.