Let’s Break Down Common Beam Sizes! If you’ve ever looked at a structural steel chart and thought to yourself, “What does 203x133x25 actually mean?” you are not alone. We get asked about beam sizes nearly every day. Here’s a simple explanation.
What do those numbers mean?
Let’s take a universal beam for example and break it down – 203x133x25. The numbers mean: 203 is the depth of the beam in millimeters. 133 is the width of the flanges, and 25 is the weight of the beam in kilograms per meter. Knowing that last number is actually pretty handy for lifting and transporting.
When ordering columns, many people still refer to them as RSJs. Technically, they are called universal beams (UB) and universal columns (UC) now. When ordering it does not matter to us which term you use, we know what you mean.
What are the most commonly used Beam sizes and what do they get used for?
We use smaller beams, such 127x76x13, for lighter work, such as putting in a lintel over a window or a small porch. For most domestic extensions we use beams in the 152 to 203 range. When it’s commercial work, it’s usually 254 or upwards. It can be a lot bigger depending on the spans involved. Ultimately, the engineer is the one that specifies what you need based on the load and the span.
We understand that you’d want to play it safe and order bigger but additional costs and required equipment can make that a hassle. Trust the calculations. Getting the length right Standard length at the mill are 6, 7.5, 9, and 12 meter increments. Most lintels fall between 2 to 4 meter bearings. 254x146x43 and weighing over 200 kg, you’ll want the right equipment to lift and transport it. Locally, our delivery can save you the hassle of lugging it around yourself. And so about tolerances Steel structures aren’t aesthetic. Rust and rough edges, which don’t impact the integrity of the steel, along with some missing mill scale are common occurrences and completely normal. If you want something painted or galvanized, just mention it during the order so we can help. The deviations from what’s standard can vary as well, for dinstance a 203mm beam might actually measure 206mm or 200mm and is still within the specs.
Structural engineers take care of this, but what about second-hand beams? This is something we have to deal with sometimes. Although some reclaimed beams may look cheaper, it is not worth the money you lose with no paperwork, no grade guarantee, and the possibility they have been drilled or notched already. For anything structural that needs building control approval, it is not worth the risk to select reused beams.
How to Place Orders
Please have the sizes and the number of lengths that you need ready when you call. If you have this engineered, it should say something like, “1 No. 203x133x25 UB @ 3.6m long”. That’s all we need to know. We will confirm the price with you, and check stock (or how quickly we can procure the item), then arrange delivery or collection. Most structural sections we stock as standard. If something unusual needs to be ordered in it usually takes a few days. So, check stock before you tell the builder it will be there Tuesday morning.
Leave a Reply