# MGP10 vs MGP12: Grade Is One Part of the Specification Understand machine-graded pine labels and why grade, section, treatment and approved design must be checked separately. - Canonical HTML: https://www.chippy.tools/building-codes/au/framing/mgp10-vs-mgp12/ - Publisher: Chippy Tools - Updated: 2026-09-06 - Market: au - Code edition / reference: Timber grade guide; check the project design - References: AS 1684.2 - Scope: Australian housing framing: reading plans, references and product details. No permitted member spans are supplied. - Source text checked: 2026-09-06 - Review scope: Public source text checked for this explanatory guide. No licensed span-table values or project design are verified. ## MGP10 and MGP12 are timber grades MGP means machine-graded pine. MGP10 and MGP12 describe grades with different structural properties. They do not describe the timber’s size or treatment. Choose the grade shown in the design, then check the rest of the product details. ## What changes with the grade? [WoodSolutions’ in-grade testing guide](https://www.woodsolutions.com.au/resources/standards-codes/quality-control-1/grade-testing) explains how tested pine properties form the MGP grades. Strength describes resistance to failure. Stiffness describes how much timber bends under load. Both matter in a frame. MGP12 is a higher grade, but it does not promise a fixed increase in span. A member may be limited by bending, deflection or another part of the design. Do not multiply a span by the ratio of the grade numbers. | Check | MGP10 | MGP12 | |----------------|----------------------------------|----------------------------------| | Strength grade | Match the MGP10 design entry | Match the MGP12 design entry | | Section size | Read the size on the plan | Read the size on the plan | | Treatment | Check the separate product mark | Check the separate product mark | | Permitted span | Depends on the whole design case | Depends on the whole design case | A grade choice is not a choice of timber size. Nor is it proof of outdoor or ground-contact suitability. ## Read the mark, not the paint colour [WoodSolutions’ grading guide](https://www.woodsolutions.com.au/resources/standards-codes/quality-control-1/machine-stress-grading) describes machine grading and grade marks. Use the mark and supplier records to identify the grade. Appearance alone is not a reliable check. An F-grade is a different grade designation; do not invent an MGP equivalent from its number. ![Four separate order fields: MGP grade, section size, treatment and use, and design member mark.](https://www.chippy.tools/building-codes/au/framing/mgp10-vs-mgp12/workflow.svg) **Diagram labels:** READ THE TIMBER ORDER; CHIPPY TOOLS; READ THE TIMBER ORDER; 1; Grade: MGP10 or MGP12; Use the grade specified in the design; 2; Section size; Check depth and width separately; 3; Treatment and use; Match the site exposure and product; 4; Member mark; Link the timber to the plan and order *Chippy Tools timber-label checklist. Grade context: WoodSolutions machine grading and in-grade testing guides. Labels are not a span table.* ## Check a proposed swap Suppose the plan lists MGP12 and the delivery contains MGP10. Set the mismatch aside and ask the supplier to resolve it. Send a photo of the grade mark and the plan item. Do not install it on the basis that the dimensions match. The reverse swap still needs a check. A pack of MGP12 could have a different section or treatment from the specified MGP10 product. Ask the designer to accept the full product change. Keep the response with the order. ## Make the timber order easy to check Record the member mark, grade, section, length, treatment and quantity on one line. Keep the supplier’s product code alongside them. Check the docket and timber marks at delivery. Raise missing or unclear marks before cutting the stock. Use the [AS 1684 input guide](https://www.chippy.tools/building-codes/au/framing/as-1684-span-tables-explained/) when comparing a design entry. For Queensland work, also check the [species guide](https://www.chippy.tools/building-codes/au/qld/construction-timbers-queensland/). The [Chippy Tools code-check sheet](https://www.chippy.tools/building-codes/printables/#code-check) gives you a place to record the reference and open questions. ## Sources - [WoodSolutions: in-grade testing and MGP grades](https://www.woodsolutions.com.au/resources/standards-codes/quality-control-1/grade-testing) - [WoodSolutions: machine grading and grade marks](https://www.woodsolutions.com.au/resources/standards-codes/quality-control-1/machine-stress-grading) Publisher links identify the standards. This review did not inspect or reproduce their licensed span tables. - [AS 1684.2:2021 publisher catalogue](https://store.standards.org.au/product/as-1684-2-2021) Content adapted from the National Construction Code 2022, provided by the Australian Building Codes Board under the CC BY 4.0 licence. This page is general information for tradespeople and is not compliance, engineering or legal advice. Requirements are subject to state and territory variations and adoption timing. Always confirm requirements with your building certifier and relevant state authority. ## Frequently asked questions ### Is MGP12 always better than MGP10? MGP12 is a higher grade, but the right product is the one that matches the design. Size, treatment, supports, connections and loads still matter. A higher grade alone does not approve a longer span. ### Does MGP12 mean the timber is treated? No. MGP is a strength grade. Check treatment and intended use separately on the product details and plans. ### Can I replace MGP12 with MGP10 of the same size? Get the change checked against the design before installation. Equal dimensions do not mean equal structural properties. ### Can I identify the grade by paint colour? Use the grade mark and supplier records. Colour or appearance alone is not a reliable way to confirm the grade. ## Source-check references - [WoodSolutions: in-grade testing and MGP grades](https://www.woodsolutions.com.au/resources/standards-codes/quality-control-1/grade-testing) - [WoodSolutions: machine grading and grade marks](https://www.woodsolutions.com.au/resources/standards-codes/quality-control-1/machine-stress-grading)