Exterior CLS Treated Timber

"CLS" stands for Canadian Lumber Standard.

In the UK, the term "CLS Timber" generally refers to timber with these characteristics:

• kiln-dried
• planed smooth faces
• eased/rounded edges
• softwood

It's commonly used for stud walls, partitions, framing and other internal construction work.

It is usually made from spruce, pine or fir ("softwood").