Red cedar lumber grades

It is difficult to fully explain the grading of red cedar lumber in one minute, so I can only give a simple summary here.

First, let's imagine we want to process a batch of red cedar logs. Before processing, we need to know:

1. There are three standards for plate grading

A) NLGA

NatioThe standard grading rules for Canadian lumber issued by the nal lumber grades authority;

B) PLIB

Export R-LIST issued by Pacific Lumber Inspection Bereau;

C) Commercial standards: The factory combines market conditions or customizes the products after consultation with customers.

2. The grading of boards is often based on the purpose of the target product.

In the first stage, after the logs are processed into boards, the grades can be divided into three categories:

1. Grades of knot-free materials and those that can be reprocessed to produce knot-free materials

A little more detail:

Knot-free lumber is called "industrial clear" in NLGA and is divided into three types: "B&Btr/C-clear/D-clear";

In R-list it is called "R-llist clear",

There are two types: "#2clear/#4clear also known as 401clear";

There are many commercial standards, such as "straight grain grade"/"85/15clear" and so on.

2. Sectional material - the later products can be used in "whole length"

Because many materials are still semi-finished products at this stage, they are temporarily classified into:

• Primum knotty--no limit on live knots, few dead knots, and very small knots. It is also called appearance knotty or commonly known as landscape grade. This product is the raw material for producing various products with STK (select tight knotty) potential.

• Performance knotty is also called No2 and better structure. It has certain structural strength but the surface status allows missing edges and dead knots, including sel structure/#1/#2structure.

3. Knotty material - basically needs to be reprocessed before it can be used

• Utility level

• Economy Class

• Chop grade (50% short, knot-free wood can be cut)

• Cutstock/trim ends/trim blocks etc. can only be used to process very short (e.g. 20-30cm to 7 feet) grades of material.

In the second stage, the above boards or squares or flitches are processed by various reprocessing factories to achieve different target products and are re-classified. For example:

1. Outdoor terrace

In NLGA, there are only two types: "select patio" and "commercial patio".

In actual commercial use, the no-section can be divided into

“Architect clear”/“custom clear”; those with knots can be divided into “architect knotty/custom knotty”.

2. Indoor and outdoor wall panels including bevel panels

Quality from best to worst includes:

• Clear VG heart (straight grain without knots or white edges)

• Clear heart (no knots or white edges)

• C and better clear

• Proprietary

• Standard and better

• Rustic (grade defined by the rough sawn surface, with the rough side facing outwards)

• Select knotty

• Architect knotty

• Various finger-joined and spliced ​​products

3. Beams and timbers with a certain load-bearing capacity

• D and Better clear (refer to NLGA for details)

• appearance knotty

• No2. And better structure

• Standard (for load-bearing purposes only and not for exposed surfaces)

4. Materials that still have certain utilization value after the following processing, such as:

• utility and better (with NLGA Grade 3 as the lower limit)

• 3-6 feet of short clear

• Shorter trim blocks from 8 inches to 3 feet (blocks can be customized to 100% knotless, 80% knotless, etc.)

• Chop grade - for long materials over 8 feet, more than 50% of the clear materials over 8 inches can be taken

• Processing of various cutstock from one length of product to the next

The above is just a brief overview of the grading of red cedar, without a detailed description of each grade.