Load bearing wall assessment - before the sledgehammer

What is load bearing wall assessment?

A load bearing wall carries weight from above - floor joists, a wall on the storey above, a roof member, or a concentrated point load - and passes it down through the structure to the ground. Working out whether a particular wall does that means tracing the load path: what is directly above it, which way the joists run and where they bear, and whether anything concentrated lands on it. Removing one is entirely routine work when it is engineered. What most often blows the budget is not the beam - it is the plumbing stack, ducts or electrical panel living inside the wall.

Signs you need load bearing wall assessment

• You are planning an open-plan kitchen, a wall between kitchen and living room, or removing a wall to make one large room
• The wall runs perpendicular to the direction the floor joists above it run
• A wall on the storey above sits directly over it, or nearly so
• There is a beam, a post or a column somewhere below it - in the basement or crawl space - roughly in line
• The wall sits near the middle of the house rather than at the edge of a room addition
• A contractor has already given you a price to remove it and you would like a second view before you commit
• You are adding weight above rather than removing a wall - a new bathroom, a heavy tub, a stone counter, a converted attic

Seeing something not on this list? Browse structural repair problems by symptom →

How load bearing wall assessment actually works

1. 1

   Trace what is above, not what the wall looks like

   The determination starts upstairs and below, not in the room you want to open. Which direction do the floor joists run, and do they bear on this wall or pass over it? Is there a wall above, and does it line up? Is a roof member, a strut or a purlin landing here? Is there a post, a beam or a column below it? Load arrives from above and has to continue to the ground, and the question is always whether this wall is part of that route.

   Watch forA judgement made from inside the room. Without looking above and below, nobody is tracing anything - they are guessing from the wall's position and thickness.

2. 2

   Understand why the internet tests are unreliable

   The common rules of thumb - perpendicular joists, interior versus exterior, wall thickness, whether it sounds hollow, whether it runs the length of the house - are generalisations that describe common construction, not rules your house obeys. Renovations move load. Walls get added and removed. Original bearing walls get replaced by beams by previous owners, and non-bearing walls get pressed into service when someone puts a post on them. Any of these makes the rules of thumb wrong, and the tests give no warning when they are.

   Watch forTreating a confident answer from a video as a determination. The tests are right often enough to feel reliable and wrong often enough to matter, and there is nothing in them that tells you which case you are in.

3. 3

   Add the case nobody covers - the point load

   A wall can be carrying almost nothing along most of its length and taking a large concentrated load at one spot, where a post, a girder truss, a roof member or a beam from another part of the house lands. Point loads do not look like anything from below and they do not follow the rules of thumb. They are also the reason a header sized on general assumptions can be wrong on an otherwise ordinary-looking wall.

   Watch forA quote for a header issued without anyone going into the attic. Point loads live where you cannot see them from the kitchen.

4. 4

   The engineer's specification, and what it actually contains

   For a bearing wall the deliverable is a specification: the replacement beam or header sized for what it carries and how far it spans, the posts or columns at each end sized to take that load, and the load path from those posts continuing down to something adequate - often requiring work below at a beam, a post or a footing. Every one of those numbers comes from the engineer. Where a permit is needed, this usually appears as a sealed drawing or letter.

   Watch forA beam size given verbally on site. That number determines whether your ceiling holds, and it should exist on paper with a professional's name on it.

5. 5

   The load path below the wall you are removing

   Load concentrated into two posts has to go somewhere. Frequently the beam, the post or the footing beneath the new post positions was never sized for a concentrated load, and the specification includes work in the basement or crawl space. This is the part homeowners are least expecting and it is very often unavoidable - the ceiling opens up beautifully, and the bill includes a new footing under the floor.

   Watch forA scope that stops at the beam and says nothing about what is under either end. The load did not stop there.

6. 6

   Temporary support during removal

   Before the wall comes out, temporary walls or shoring take the load on both sides, and they need a route down to something that can carry it - on both floors, if there is a floor between them and the ground. The temporary work is genuinely structural, it is where accidents on this job happen, and it is worth as much of your attention as the permanent beam.

   Watch forTemporary support on one side only, or shoring set on a floor with nothing beneath it. Ask what the shoring bears on, floor by floor, down to the ground.

7. 7

   The hidden services - where the budget actually goes

   This is the point of the page. Open a bearing wall in a kitchen and you routinely find a plumbing stack, supply and waste runs, an HVAC duct chase, several circuits, and occasionally the electrical panel itself. Relocating a stack means opening floors and ceilings and coordinating trades, and it frequently costs more than the structural work. The honest version of this conversation happens before you sign, not when the drywall is off.

   Watch forA quote with a small allowance for "any services found". That allowance is doing an enormous amount of work. Get the wall opened up exploratorily, or get the allowance defined properly.

8. 8

   Permit, inspection, and closing out

   Removing a bearing wall is structural alteration and generally requires a permit and inspection, with the engineer's sealed documentation supporting it. Inspections happen at the points where the beam, its supports and the connections are visible - which is before the drywall goes on. Then get the engineer back for a verification letter before it is all closed up.

   Watch forA remodeller offering to do it without a permit because it is "part of a kitchen job". Unpermitted removal of a bearing wall is one of the worst findings a buyer's inspector can hand your future buyer.

What does load bearing wall assessment cost?

Two very different numbers hide behind one job. The engineering and the beam are often the smaller part; the larger part is relocating a plumbing stack, ducts or a panel, plus new posts and footings below. Get structural work and services relocation quoted as separate lines.

See the full load bearing wall assessment cost guide - by material, size and region →

If the number is the problem, here are the ways people pay for it →