MGP10SpanTables
MGP10 timber span tables, decoded

Size MGP10 framing the right way.

What the grade means, how to read the span tables correctly, and a builder that assembles your exact lookup for floor joists, bearers, rafters and lintels.

Open the Span Spec BuilderHow to read the tables
Diagram of a timber beam spanning between two supports under loadSpan (L)Load ↓  ·  Deflection (δ) · Support reactionsThe span is the clear distance a member bridges between supports

Important: this is an independent educational guide, not engineering advice. Allowable spans must be read from the current AS 1684 tables for your exact situation and verified by a qualified engineer or building certifier. Nothing here replaces professional design or building approval.

Span Spec Builder

Build your exact span-table lookup

Answer a few questions and we assemble a clean specification to take to the official AS 1684 tables or your engineer. This tool does not output an allowable span — that figure must come from the current tables for your exact situation.

Before you cut — confirm every item

    Not an allowable span. Read the maximum span from the current AS 1684 tables (or a manufacturer's published tables) for these exact parameters, and have your design verified by a qualified structural engineer or building certifier. Compliance with the National Construction Code is your responsibility.

    The fundamentals

    Three things that make span tables click

    📐

    Know the inputs

    A span lookup turns on a handful of variables: member, size, spacing, single vs continuous, load width and wind class. Learn them once and the tables stop being scary.

    ⚖️

    Strength and stiffness

    Timber can be strong enough and still sag. Span tables build in deflection limits, which is why you size to the table value — not to what 'feels' solid.

    ✅

    Verify, then build

    We help you assemble the right lookup, then point you to the official AS 1684 tables and a qualified engineer. Safe sizing is checked sizing.

    Guides

    Everything you need to size with confidence

    A length of pine stamped with the MGP10 stress gradeMGP10Machine Graded Pine — every piece is stamped with its stress grade

    What Is MGP10? Machine Graded Pine Explained

    MGP10 is a machine-graded pine stress grade used across Australian timber framing. Here is what the grade means, how it compares to MGP12, MGP15 and F-grades, and where it is used.

    Diagram of a timber beam spanning between two supports under loadSpan (L)Load ↓  ·  Deflection (δ) · Support reactionsThe span is the clear distance a member bridges between supports

    How to Read MGP10 Span Tables (Step by Step)

    MGP10 span tables look intimidating but follow a clear logic. Learn the inputs you need — member, size, spacing, span type, wind class, load width — and how to find the right value.

    Floor joists laid across two bearers at regular spacingFloor joists span across bearers, set out at regular spacing (e.g. 450 or 600 mm)

    MGP10 Floor Joist Spans

    How MGP10 floor joist spans work — the role of spacing, single vs continuous span, deflection and load, plus why decks are a different case. A practical orientation, not a number to copy.

    A bearer on posts carrying floor joists, showing floor load widthFloor Load Width (FLW)Bearers carry the joists; their span depends on Floor Load Width and post spacing

    MGP10 Bearer Spans and Floor Load Width Explained

    Bearers carry the joists, and their span depends heavily on floor load width. Learn how bearers, joists and posts work together and how to approach an MGP10 bearer span lookup.

    Roof rafters spanning from a ridge under roof loadRafters span from ridge to wall; sizing depends on Roof Load Width, roof mass & wind

    MGP10 Rafter and Roof Member Spans

    Roof members add roof load width, roof mass and wind into the mix. Learn how MGP10 rafter and roof beam spans are determined and which inputs you must get right.

    A lintel spanning over a wall openingOpening (door / window)A lintel carries the load above an opening across to the supports each side

    MGP10 Lintels and Beams

    Lintels carry the load above doors and windows. Learn how MGP10 lintel spans are approached, why point loads change everything, and when you need an engineered beam instead.

    Browse all 10 guides →

    Kit out the job

    Accurate set-out and clean cuts start with the right tools. See our hand-picked framing tools and reference recommendations.

    See tools & reference