Before the 30-day pause of sweeping U.S. tariffs on Canadian goods was announced Monday, the chief operating officer of Freeman Lumber didn't know which American customers the company would still have going forward. 

"It's been chaotic to say the least," said Marcus Zwicker, with the Greenfield, N.S., sawmill business. "A significant number of customers on the other side of the border … couldn't afford to pay" the tariff. 

More than half of the products Freeman Lumber makes are sold to clients in…