A steel beam is far stiffer than an LVL beam of the same depth, so for the same span and load, steel does the job with a much shallower section. Steel's modulus of elasticity is about 200,000 MPa, while common LVL grades sit around 12,000 to 14,000 MPa, which makes steel roughly 14 to 17 times stiffer as a material. LVL (laminated veneer lumber) closes the gap by being deeper and wider. Which one is right for your opening comes down to how much depth you can give up, the loads involved and who is doing the install.
This article compares the two on strength, stiffness, span and depth. If your main question is price, see our companion post on steel beam vs LVL cost. Either way, the beam in a house is sized by a designer or engineer, not picked from a comparison.
What LVL is, and how each beam gets sized
LVL is an engineered wood product made from thin wood veneers glued together with the grain running in the same direction, then cut into beams and headers. Because defects are spread out through many thin layers, it's more uniform and stronger than sawn lumber of the same size. It's typically sold in 1-3/4 in (about 45 mm) thick plies that are nailed or bolted together into two-, three- or four-ply beams.
A steel beam in Ontario homes is usually a wide-flange W-shape such as a W200x27, named by nominal depth in millimetres and mass in kilograms per metre. Our guide on how to read steel beam sizes explains the naming.
The two are sized in different ways:
| Steel W-beam | LVL beam | |
|---|---|---|
| Ontario code span tables | Yes: Table 9.23.4.3 (floors) and Tables 9.23.4.3.-A to -J (roof and floor) in the 2024 OBC | No: proprietary product |
| How it's sized | From the OBC tables when the job fits them, otherwise engineered | From the manufacturer's load tables or software, or by an engineer to CSA O86 |
| Material standard | Grade 350W steel to CSA G40.21 for the OBC tables | Manufacturer's grade and published design values |
The 2024 Ontario Building Code requires wood structural members to conform to CSA O86, "Engineering design in wood," and its built-up beam tables cover sawn lumber only. So when someone asks for "LVL vs steel beam span tables", the honest answer is that only the steel side has a table in the code. The LVL side comes from the manufacturer whose product is on site.
Stiffness: why steel stays shallower
In house framing, beams are usually governed by deflection (how much they sag under load) before they run out of strength. Floors that bounce, cracked drywall and doors that stick are deflection problems. Deflection depends on two things: the material's stiffness (E) and the section's shape (its moment of inertia, I). Their product, EI, is the bending stiffness.
That makes for a useful like-for-like comparison. The table below lines up common W-shapes against LVL beams of roughly the same bending stiffness. The steel values use CISC section properties and E = 200,000 MPa; the LVL values assume 45 mm plies and E between 12,000 and 14,000 MPa.
| Steel beam | Steel depth | LVL of similar bending stiffness | LVL depth | LVL width |
|---|---|---|---|---|
| W150x22 | 152 mm | 2-ply 11-7/8 in | 302 mm | about 89 mm |
| W200x27 | 207 mm | 4-ply 11-7/8 in | 302 mm | about 178 mm |
| W250x33 | 258 mm | 3-ply 16 in | 406 mm | about 134 mm |
| W310x39 | 310 mm | 4-ply 18 in | 457 mm | about 178 mm |
The pattern is consistent: to match a steel beam's stiffness, an LVL needs to be roughly one and a half to two times as deep, or much wider at the same depth. In a basement with limited headroom, or a wall opening where the ceiling has to stay flat, that difference often decides the question.
Treat the table as an illustration of the gap, not as a substitution chart. It compares stiffness only. Real sizing also checks bending strength, shear, bearing, lateral stability, long-term load effects (wood creeps under sustained load, steel does not in any practical sense), point loads and vibration, and each manufacturer's LVL grade has its own values.
Span: where each one runs out
For the same depth, steel spans further. For the same span, steel is shallower. In practice:
- Short to moderate spans with a uniform floor load are well within LVL's range, and a multi-ply LVL often fits where the floor joists are deep enough to hide it.
- Longer spans push LVL deeper and wider, and at some point it no longer fits in the joist depth or it starts eating headroom.
- Steel's span range in the OBC tables runs well beyond typical residential LVL headers. Table 9.23.4.3, for example, lets a W310x39 carrying one storey span 11.4 m with a 2.4 m supported joist length. Our steel beam span tables guide walks through how to read it.
Removing a basement post is a common example. Taking out one post roughly doubles the span of the beam it supported, and the beam over that doubled span also carries more load, so the required stiffness goes up sharply. That's where steel usually takes over, because a deep multi-ply LVL would hang well below the joists.
Depth, headroom and flush beams
Depth is where the comparison becomes practical:
- Dropped beams hang below the joists. Every millimetre of beam depth is a millimetre off the headroom underneath, which matters in basements and under main-floor openings.
- Flush beams sit in the same plane as the joists, with joists hung from the beam's sides. A flush beam has to be no deeper than the floor framing if you want a flat ceiling. A W200 or W250 often fits inside a floor built with 2x10 or 2x12 joists, where an equally stiff LVL may not.
- Width matters in walls. A four-ply LVL is about 178 mm wide, wider than a 2x6 wall, so it may need to be furred out or set in a deeper pocket. A steel beam's flange widths are fixed by the section, so check them against the wall.
Steel beams supporting wood joists normally get a wood nailer bolted to the top flange so the joists and subfloor can be fastened. When joists hang from the side of a steel flush beam, the connection is detailed on the drawings.
How much weight can an LVL beam support?
It's one of the most searched questions about LVL, and there isn't a single answer. The capacity of an LVL beam depends on:
- Depth and number of plies. Depth has the bigger effect, because stiffness rises with the cube of depth.
- Span. Doubling the span reduces the load a beam can carry far more than half.
- Grade. Each manufacturer's grades carry their own published design values.
- Load type. A uniform floor load is different from a post or wall bearing at mid-span.
- Bearing length. Wood can crush at its supports, so LVL beams carrying heavy loads need adequate bearing length, set out in the manufacturer's tables.
Manufacturers publish load tables showing what each size can carry over a given span, and many offer sizing software through lumber dealers. Those tables are the right tool for checking an LVL, and an engineer is the right person when the load path is unusual. The same applies to steel: OBC tables cover simple cases, and anything with concentrated loads is engineered.
When steel makes sense and when LVL does
Neither material is better in every case. Here's how the decision usually breaks down:
| Situation | Usually favours |
|---|---|
| Long clear span, such as removing posts in a basement | Steel |
| Headroom is tight or the ceiling must stay flat | Steel |
| Concentrated loads from posts or walls above | Either, engineered; steel often shallower |
| Moderate span inside a wood-framed wall or floor | LVL |
| Framer installing during framing, no heavy equipment | LVL |
| Limited access where one long piece won't fit | LVL plies, or steel with a designed splice |
| Beam supports another beam or a point load from a roof | Engineered either way |
Installation is part of the picture. LVL goes in one ply at a time and is fastened with nails, screws or bolts by a framing crew. A steel beam is heavier per piece and needs a plan for getting it into place, but it arrives cut to length with holes, plates and connections already done. Our post on cost to install a steel beam in a basement covers what that job involves.
Have it designed before you choose
Whether the beam is steel or LVL, it's a structural member. Replacing, adding or upsizing a beam, or removing a post or wall, needs a qualified designer or engineer and, in GTA municipalities, usually a building permit. The designer sizes the beam for the real loads, specifies the bearing and posts, and makes sure the footings under those posts are adequate. If you're comparing options, ask your designer to size both, so you're comparing like with like on depth and on what each needs at the supports.
Getting a steel beam priced
If your design calls for steel, or you want a steel option to compare against an LVL, send us your drawings or beam schedule. We fabricate W-beams cut to length with plates, holes and connections ready for install, along with the posts that go under them. See our steel products for what we supply.
Frequently asked questions
Is a steel beam stronger than an LVL beam?
For the same depth, yes, by a wide margin. Steel is roughly 14 to 17 times stiffer than common LVL grades, so a steel W-beam can carry the same load over the same span with much less depth. An LVL can match a steel beam, but it has to be deeper, wider or both.
How much weight can an LVL beam support?
There is no single number. An LVL's capacity depends on its depth, number of plies, grade, span, bearing length and the type of load. Manufacturers publish load tables and sizing software for their own product, and those, or an engineer, give the answer for your beam.
Are there LVL span tables in the Ontario Building Code?
No. The 2024 OBC has span tables for sawn lumber, built-up wood beams and steel W-beams, but LVL is a proprietary product. It is sized from the manufacturer's published tables or software, or designed by an engineer to CSA O86.
Can I swap an LVL on my drawings for a steel beam?
Only with the designer's approval. The two are not interchangeable piece for piece: the steel section, its bearing, connections, lateral support and post loads all have to be checked, and the change usually needs to be reflected on the permit drawings.
