Removing the Middle Post: A Structural Engineer’s Solution to Open Concepts

Many older Ontario homes have a common frustration: a load-bearing post right in the middle of the living room or basement. While these posts block your open-concept renovation plans, they serve a critical purpose.

Removing them isn’t cosmetic work—it’s a major structural change. Here is how we engineer a safe solution without sacrificing headroom.

The Structural Physics: Why is the Post There?

In older homes, builders used standard lumber (like built-up 2x10s) for beams. This wood is relatively weak and can only span about 8 to 10 feet before it starts to sag.

To prevent sagging, builders added a middle post. This post cuts the span in half and sends the weight down to the foundation. If you remove the post, you double the span. The original beam is not strong enough to handle that gap alone. 

The Engineering Solution: Steel vs. Engineered Wood

To bridge that gap without a middle support, we need a material that is significantly stronger and stiffer than the original wood. Once we calculate the Tributary Area (how much floor and roof load is resting on the beam), we select a material that can handle the stress. The deciding factor is almost always Headroom.

To remove a post, the beam has to work much harder. If we use a material that isn't strong enough, it will require massive depth (height) to stay stiff, which lowers your ceiling height.

Structural Solutions for Removing the Middle Post

Two common approaches to provide safe and open-concept layouts:

1. Steel Beams

   Steel has a very high strength-to-depth ratio. A steel beam (W-shape) can carry massive loads across a long span while remaining relatively shallow (often 8 to 10 inches deep). This allows the contractor to install "flush beams" hidden inside the ceiling joists or minimize the size of the bulkhead, keeping your ceilings high and open.

1. Engineered Wood Beams

   Laminated Veneer Lumber (LVL) or Glulam beams are stronger than old-fashioned wood, but it has limitations compared to steel.

   
   

   1. The Depth Issue: To span a large room without a middle post, an LVL beam might need to be 16 to 24 inches deep. In a basement or living room, this would create a very low bulkhead that ruins the "open concept" feel.

   2. The Bungalow Exception: Engineered wood is often the perfect solution for bungalows. Since the beam is supporting the roof, we can often push a deep LVL beam up into the attic space. The depth doesn't matter because it is hidden in the attic, allowing for a flat ceiling below without the cost of steel.

The Hidden Challenge: The Load Path

The most critical aspect of removing a post—and the one most often overlooked by non-professionals—is the Load Path Transfer.

When a middle post is removed, the weight that used to sit in the center of the room is shifted entirely to the ends of the new beam. This creates massive concentrated point loads at the bearing points. 

Furthermore, the structure must be temporarily supported during this transition. If temporary shoring isn't placed correctly to handle these loads while the post is being removed, the house can shift or crack before the new beam is even installed.

A comprehensive design includes:

• Shoring Design: A plan for temporary supports, ensuring the contractor can safely hold up the house during construction.

• Beam Specification: Precise sizing of the new Steel or Engineered Wood (Multi-ply LVL or Glulam) member.

• New Columns: Sizing vertical supports, typically HSS steel or solid wood posts to carry the concentrated loads.

• Load Path Verification: Determining exactly where the new columns land below, whether onto a foundation wall, a structural beam on the lower level, or an isolated footing.

• Foundation Capacity: Verifying that the existing concrete footing is wide and thick enough to handle the new point loads, or if any upgrade is required.

Final Thoughts

Removing a load-bearing post can completely transform a home, but it must start with a structural design, not a guess.

At Parsways Inc., we make the process simple. We calculate the loads, design the most efficient beam for your space, and provide the permit-ready structural drawings you need to start construction with confidence.