This is built on the same Australian Standards engineering method I use day to day (AS 1720 timber design, AS 1170 loads). It's deliberately a rough guide only — not a design, and definitely not a certificate. Use it to understand your project, then let me check it properly.

Tell me about your opening

Your project

Don't worry if you're not sure on a number — leave the sensible default and the Desktop Review will confirm everything.

Tiles are much heavier than metal sheeting — it makes a real difference.
The clear distance the beam has to span across the gap.
beam / lintel opening width
The gap the beam must cross — measure the clear opening, not wall-to-wall.
2.4 m
Roughly, the distance from this wall to the next wall (or support) that shares the load. If unsure, leave it — bigger is safer.
tributary width your wall (the beam) support support
About half the distance to the support on each side rests on your wall — that shaded width is what to enter.
4.0 m
Indicative result only

Typical size — an example, not your final spec
Opening width
Estimated load carried
Estimated bending demand
Rough estimates from typical values — your real numbers will differ. This is why a proper review matters.

⚠ Please read — this is not a design or a certificate

This free tool makes a lot of safe assumptions and cannot see your actual house. It does not account for:

  • The real loads, wall above, point loads from other beams or trusses, or whether the wall is actually load-bearing
  • Connections, supports, bearing at the ends, propping during the work, and what the beam sits on
  • Wind, the timber grade actually available, deflection of brittle finishes, and council/NCC requirements

Any size shown is an indicative example of what similar openings often use — it is not a recommendation for your specific opening. Do not order materials or start work from this result. A registered structural engineer must review your specific situation.

Ready for a real answer?

Three simple steps — start small, upgrade only if you need to. Each step's cost comes off the next one.

Step 1 · Start here

Desktop Review + Call

$149
  • You upload photos & a few measurements
  • A registered engineer will review it
  • A short phone call to talk it through
  • A written preliminary opinion
Request a Desktop Review
Step 2 · If needed

Site Inspection

🔒 Price shown after your review
  • I visit and check the actual structure
  • Confirm what's load-bearing
  • Priced by your site's location
  • Your $149 review fee comes off it
Book after your review
Step 3 · To build & certify

Engineering Certificate

🔒 Price shown after your review
  • Signed, council-ready beam design
  • The document your builder/certifier needs
  • Earlier fees credited
Issued after inspection