Removing a Load-Bearing Wall in a Two-Storey or Split-Level

Removing a load-bearing wall in a two-storey house is usually possible, but what the wall carries, and where the new posts have to land, changes a lot depending on which floor the wall is on. A main-floor wall in a two-storey typically carries the second floor and sometimes part of the roof, so it needs a larger beam and solid posts down to new or existing footings in the basement. A second-floor wall usually carries less, but its posts have to travel through two floors to reach the ground. Split-levels add stepped foundations and half-storey offsets that make the load path harder to read. Every case needs a design and, in almost every Ontario municipality, a building permit.

This post walks through how the job differs by floor and house type. For the general sequence (design, permit, shoring, removal, beam, inspection), see our step-by-step guide to removing a load-bearing wall and installing a beam.

Why the floor matters

Every load-bearing wall is one link in a chain that runs from the roof to the footings. When you take a wall out, the beam that replaces it collects the same load and drops it onto two (or more) points instead of spreading it along a line. Those points then need a continuous path down to the soil.

Three things change with the floor the wall is on:

• What the beam carries. Floors, walls, roof and snow above the wall all come down onto the beam. The higher the wall, the less there is above it.
• How far the posts travel. A post at the end of a basement beam sits on a footing a few metres below. A post at the end of a second-floor beam has to pass through the main floor and the basement first.
• How much finish gets opened. Every floor the load path crosses is another ceiling, wall or floor that may need to come apart and go back together.

Removing a load-bearing wall on the first floor of a two-storey

This is the most common version: opening the kitchen to the living room, or the dining room to the family room, on the main floor of a two-storey home.

What the beam carries. A main-floor bearing wall in a two-storey usually supports the second-floor joists, and often there is another bearing wall stacked directly above it on the second floor carrying ceiling joists or roof load. If so, the new beam carries the second floor plus whatever that upper wall delivers. Our post on the steel beam size to support a second floor explains how the Ontario Building Code tables handle a beam carrying one floor versus a floor plus the roof, and when the tables stop applying.

Flush or dropped. A dropped beam sits below the joists and is simpler to install. A flush beam sits in the same depth as the joists, with the joists hung from it, so the ceiling stays flat. Flush beams are popular in open-plan kitchens, but they need more temporary shoring and more careful connections. Steel is common here because it carries more load in less depth than wood; see steel beam vs LVL for the comparison.

Where the posts land. The posts at each end come down inside the walls at the ends of the opening and bear on the basement below. That usually means one of three things in the basement:

• The post lands on an existing foundation wall, which is the easy case.
• The post lands over an existing basement beam, and the designer checks whether that beam and its posts can take the new point load.
• The post lands in the middle of the basement floor, and a new column and footing go in under it. The basement slab isn't a footing, so it's cut open and a proper footing is poured. Our post on lally column footing requirements covers what that footing involves.

Removing a load-bearing wall on the second floor

Second-floor bearing walls usually support ceiling joists, and in older homes they may also carry struts or knee walls from the roof framing. The beam that replaces them is often smaller than a main-floor beam, because there's no occupied floor above.

The catch is the load path. The posts at the ends of a second-floor beam carry their load down through:

1. The second-floor framing, where solid blocking under each post keeps the load from crushing the joists or subfloor.
2. A wall or post on the main floor directly below, which may not exist yet.
3. The basement, to a footing or foundation wall.

If the main floor below the post is an open area, a new post has to go there too, or the second-floor beam has to be arranged so its ends land on walls that already carry load down. That's the main design puzzle on second-floor removals.

Beam in the ceiling or the attic. On a top floor, there's sometimes the option of putting the beam above the ceiling in the attic and hanging the ceiling joists from it, so nothing shows in the room below. Whether that works depends on the roof framing, attic access and insulation, and it's a call for the designer.

Bungalows: ceiling, roof and trusses

In a one-storey house, the main-floor walls carry the roof and ceiling directly, so the question is how the roof is framed.

• Rafter-framed roofs (common in older bungalows) often rely on a central bearing wall to support the ceiling joists, which may also act as ties for the rafters. Some have struts running from the roof down to that wall. Removing it changes how the roof works, not just the ceiling.
• Trussed roofs are designed to span from exterior wall to exterior wall, so most interior walls under them carry no roof load. The exceptions are girder trusses and truss layouts designed with interior bearing points. The truss drawings, or an inspection of the truss tags and layout, settle it.

Because a bungalow beam carries roof and snow load rather than floor load, its size depends heavily on the snow load for your location. Basement posts and footings follow the same rules as in a two-storey.

Split-level homes

Split-levels (backsplits, sidesplits and true split-levels) are where wall removals get unpredictable. Common features:

• Walls at the level changes often carry the ends of the upper floor's joists. The wall between a half-level family room and the kitchen above it is frequently load-bearing even when it looks like a simple partition.
• Foundations step. The lower level and the upper level sit on foundations at different heights, and a bearing wall may sit on the top of a short foundation wall. Posts from a new beam can land on the stepped wall, on a footing at the lower level, or on framing that has to be reinforced.
• Opening a wall can create a drop. Removing a wall between two levels may leave an open edge where the floors differ in height. Under Article 9.8.8.1 of the 2024 OBC, a guard is required where the difference in elevation is more than 600 mm, so the design may need a guard or half-wall along part of the opening.

Split-levels also tend to have ducts and plumbing running through the walls at the level changes, so services planning matters as much as the beam.

Who designs it and what to expect

On any floor, a load-bearing wall removal needs a design showing the beam, posts, connections, blocking and footings, and a building permit before work starts. Part 9 span tables can cover some simple cases, but beams carrying point loads, flush beams, long spans and split-level framing usually go to an engineer. Our post on whether you need a structural engineer to remove a wall explains where the line falls, and permits for load-bearing wall removal in the GTA covers the permit side.

The order on site is roughly the same whatever the floor: temporary shoring on both sides of the wall (and on the floors below where needed), wall removal, posts and footings, beam, connections, inspection, then finishing. For what can go wrong when that sequence is skipped, see the risks of DIY load-bearing wall removal.

A few planning tips that apply to multi-storey removals:

• Trace the wall down before you design the beam. Find out what's under each end of the future opening on every floor down to the basement.
• Check for stacked walls. A wall directly above or below the one you're removing usually means more load, or a load path you can reuse.
• Expect to open more than one room. Posts and blocking often mean temporary holes in finished walls or ceilings on the floors below.
• Plan access for the beam. A steel beam for a main-floor opening has to come in through a door or window. Our post on lifting a steel beam into a house without a crane covers the options.

Steel beams and posts for your opening

We fabricate steel beams and HSS posts with welded cap and base plates, holes for your connections, and splice plates where your engineer has detailed a splice, all to your designer's or engineer's drawings. We can supply and install basement beams and posts, and deliver across the GTA and Ontario. Send us your drawings for a quote, or see the beams and posts we fabricate.