Canada accused US producers of Wall Board of "dumping" the product in Western Canada a prices "below cost". The suggestion is that US producers are trying to out price Canadian producers and put them out of business.
"""A new trade dispute has broken out between Canada and the U.S. that threatens to raise prices in Canada’s already overheated housing markets.
The Canada Border Services Agency imposed a provisional tariff as high as 277 per cent on U.S. drywall imports in September after ruling that manufacturers were dumping the product, or selling it below the price in their home market, undercutting local suppliers.
The tariff has raised the price of drywall, or gypsum board as it’s also called, by as much as 30 per cent and is causing “chaos” and delays as contractors scramble for alternative sources.
Some builders say the tariff could add as much as $13,000 to the cost of a new home, which would amount to a $2.6-billion increase to the roughly 200,000 homes built in Canada each year.""" (from Globe and Mail)