What Is An RSJ Beam? The Essential Guide
What Is An RSJ Beam? The Essential Guide
You’ll also hear an RSJ called a universal beam or an I-beam, they’re the same family of product, just different names depending on who’s talking and where. What matters for your project isn’t the name, it’s getting the right profile and size specified correctly, because an undersized beam is a structural problem, not a cosmetic one.
I-Beam Or H-Beam: What’s The Difference
Both are RSJs. An I-beam has a narrower flange (the top and bottom horizontal sections) relative to its depth, which makes it efficient for spans where the load comes straight down. An H-beam has a wider flange closer to the depth of the web, giving it more resistance to loads from the side as well, which is why you’ll see H-beams used more often as columns than as horizontal beams. Your structural engineer will specify which one your project needs, this isn’t something to guess at.
When You Actually Need One
The most common trigger is knocking through a load-bearing wall to open up a living space. Take the wall out without replacing its support and the floor above has nothing holding it up, the RSJ takes over that job. Other common uses:
- Spanning a new opening for a bifold or patio door
- Carrying floor and roof loads through a loft conversion
- Replacing a failed or undersized timber lintel over a wide span
- Forming the skeleton for a new steel-framed extension or outbuilding
If you’re not sure whether a wall is load-bearing, don’t guess. A structural engineer can confirm it and calculate the exact beam size and type your span and load need, sized to Australian Standard AS 4100 for steel structures. Skipping that step is how you end up with a beam that’s either an expensive over-spec or, worse, not strong enough.
Standard Sizes Versus Custom-Cut
If your engineer specifies a common length and profile, you can usually buy it ready-made. For anything non-standard, we work with fabricators to cut it to size, which adds lead time, so get your measurements locked in early rather than at the last minute. Once it’s fabricated, we handle delivery to site, see our RSJ Steel Australia page for current stock and delivery areas.
Sourcing RSJ Beams Through AST
We supply RSJ beams to builders, renovators and trades across the country, whether that’s a single beam for a wall removal or a full steel package for a new build. We’re rolled from the same structural steel family as universal beams and columns, so if you need help figuring out which profile fits your project, get in touch and we’ll talk it through rather than just taking an order.
Get High-Quality RSJ Beams For Your Project
At Australian Steel Traders, we’ve been helping source and supply steel to the construction industry for years. There’s no project too big or too small for our team, whether you need a single RSJ beam or an entire steel structure.
Get in touch with our team if you have questions or would like a quote. We’re always happy to help, so call or email us today!