Everything you need to know about softwood lumber in Quebec

 In Floor joists, Roof trusses

Want to know more about softwood lumber? You’ve come to the right place!

Here is everything you need to know about this type of wood produced in large quantities right here in Quebec.

Short definition of softwood lumber

Softwood lumber is a primary wood product suitable for all non-heating uses. The 2 x 4s used extensively in Quebec in the construction sector are a good example of this.

Softwood lumber is available in various types, grades and sizes. These characteristics will influence its performance and therefore its use.

In Quebec, softwood lumber is also commonly referred to as “sawn softwood lumber” or “dimensional softwood lumber”.

3 main categories of softwood lumber

Softwood lumber can be classified into three main groups based on its dimensions.

Softwood lumber boards

Pieces of softwood lumber with a narrow side measuring less than 38 mm are considered boards.

Dimensional softwood lumber

Softwood lumber sections with a narrow side measuring between 38 and 102 mm are classified as dimension softwood lumber.

Large softwood lumber

To be considered heavy softwood lumber, a piece of softwood lumber must have a narrow side of at least 114 mm.

Softwood lumber classifications in Quebec and Canada

In Quebec, the Canadian National Lumber Grades Authority (NLGA) is responsible for drafting and enforcing the classification rules for softwood lumber from Canadian forests. Its work is largely based on the CSA O141 standard – Softwood lumber. For Canadian softwood lumber to be used in the United States and vice versa, these classification standards were established in collaboration with the American Lumber Standard (ALS).

The softwood lumber design values are published in the CSA O86 Standard – Design Rules for Wood Framing. These values vary according to wood type, moisture content, visual classification and mechanical grading.

All softwood lumber produced in Quebec and destined for the commercial construction sector is stamped, indicating its origin, species group, wood type and moisture content when planed.

Softwood lumber classification by wood type

Softwood lumber’s mechanical properties vary according to its type. The CSA 086 standard therefore requires that it be identified according to the wood from which it is made.

However, since some species have similar characteristics and can be used for the same kind of applications, they can be grouped in the same class.

Douglas Fir – Larch North (D Fir-L (N))

  • Douglas fir
  • Western Larch

Hemlock – Fir (Hem-Fir (N))

  • Western Hemlock
  • Amabilis fir

Spruce-Pine-Fir (S-P-F)

  • White Spruce
  • Englemann Spruce
  • Black Spruce
  • Red Spruce
  • Lodgepole Pine
  • Jack Pine
  • Alpine Fir
  • Balsam Fir

Northern Species (N. Species)

  • Western Red Cedar
  • Red Pine
  • Ponderosa Pine
  • Eastern White Pine
  • Silver Pine
  • Trembling aspen
  • Big-toothed poplar
  • Balsam poplar

Softwood lumber classification by moisture content

Wood is a material that reacts to water and ambient humidity fluctuations. The amount of moisture it contains therefore influences its behaviour and mechanical properties. This is the main reason why it is important to know whether the softwood lumber is dry or wet before using it as timber or for other purposes.

Wood is considered dry if its moisture content is less than or equal to 19% and green if its moisture content is greater than 19%.

To be officially dry, however, softwood lumber must be certified as KD (kiln-dried) or S-DRY (air-dried).

Visual softwood lumber classification

Softwood lumber can also be sorted according to its visual defects:

  • Holes
  • Nodes
  • Wood grain deviations
  • Warping
  • Colour
  • Etc.

Many sawmills are equipped with scanners that accurately measure these defects and their location on the softwood lumber. A large knot in the middle of a board will affect its strength more than a small knot in a corner.

Following this visual evaluation, the wood can be graded Select Structural, Select Structural, No 1, No 2, No 3 or Stud (Select Structural being the category with the fewest defects).

Mechanical softwood lumber classification

Softwood lumber can also be graded by mechanical stress using equipment that measures the stiffness of the pieces and their resistance to bending. In this case, it is known as MSR (Machined Stressed Lumber).

This method is governed by NLGA’s Special Products Standard (SPS) 2. Grades are appointed based on two values:

  • Allowable bending stress (Fb in lb/in²)
  • Average modulus of elasticity (E in millions of lb/in²)

The most common mechanical grades are 1650Fb-1.5E, 2100Fb -1.8E and 2400Fb -2.0E.

Because of their high density, certain species from Quebec’s boreal forest (especially slow-growing ones) are ideal for producing high-quality MSR wood. Not surprisingly, this wood harvested right here is used to manufacture machined structural components such as prefabricated roof trusses and floor joists.

The price of softwood lumber

As is the case for many goods, the price of softwood lumber tends to fluctuate according to supply and demand. For example, when production slows down or housing start increases, prices will tend to rise.

At UsiHome, we are proud to showcase Canadian and Quebec softwood lumber

As suppliers of prefabricated structural wood products, Usihome is proud to use local softwood lumber to create solid products that are designed for easy installation.

Contact us to find out how we can contribute to the success of your next construction project!

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