Hey Noah, What Are Load Bearing Walls?
As a structural engineer, I seem to be the go-to guy among my friends and family when someone wants to know if a wall in their home is load-bearing or not. When I get that phone call I often think to myself “Do they even know what a load-bearing wall is?”. So first off, I think I should explain what classifies as a load-bearing wall and how they work, and then I can go into explaining some ways I determine if a wall is load-bearing when I am helping out with my friends and family.
Some of the reasons someone would ask this question in the first place would be one of a few things. One reason would be curiosity. If you are like me, you may have that curiosity gene that just wants to learn about how things work and are constructed. The main reason would be that they are doing a renovation at their home or business that requires a wall to be removed or modified to have new door/window openings as they are worried that the structure will collapse. Nowadays it is becoming more trendy to have an open floor concept. That means that people want to get rid of their ugly walls that don’t do much for their space.
A load-bearing wall is any wall that holds up the weight of the structure above and the people/furniture supported by that structure. The floors above, roof structure, people and furniture are the “loads” that the wall has to support. A load-bearing wall transfers load all the way down to the building’s foundation. In a multi-storey building, load-bearing walls usually line up with each other from floor to floor, but this is not always the case. In a house, for example, the floor plans from floor to floor are often not consistent, so where there is a bearing wall on an upper floor there may be an open space on the floor below. You may be asking, “But where does the load go if the wall just disappears?”. Well, I can tell you that load doesn’t just magically disappear, it needs to be able to make its way down to the building’s foundation somehow. In these cases, a transfer beam or lintel is installed below the bearing wall to carry the load to each side of the opening at the lower floor. There can also be situations where a load-bearing wall sits on the floor joists which transfer the load to adjacent walls and beams.
Other than transferring load, the role of a wall in a building include:
- To separate rooms and spaces
- To provide acoustic separation and prevent sound travel
- To prevent fire from spreading from one space to another
- To provide aesthetics to a space
- To provide shelter
- To enclose conduits and plumbing
- To provide security (can’t we all just get along?!)
So now that you know what a load-bearing wall is, it’s time for some tips on how to determine if a wall is load-bearing or if it is just a partition wall that can be moved or altered with so major structural implications. It is not always easy to determine if a wall is load-bearing without having access to the ceiling or attic space to visually inspect the framing.
If you are able to see the floor framing or roof framing, you first want to locate the floor joists or roof trusses. If the wall in question is parallel to the joists/trusses, it will likely not be load-bearing. An example of a non-load bearing partition wall can be seen on the left.
When joists/trusses are perpendicular to the wall and bear on the top of the wall, that wall is bearing wall. An example of a load bearing wall call be seen on the right.
Joists are rarely continuous over the top of a wall, instead, they are often spliced over the top of the wall as dimensional lumber only available in specific lengths. For an idea of the standard lengths of dimensional lumber click here.
If you don’t have access, it is safe to say that all exterior walls are load-bearing. Exterior walls resist wind loads as well as roof and floor loads. If there is an interior wall that is continuous and in line with a wall above or below, there is a better chance that it is a bearing wall compared to section of short walls that jog in and out. If you only have access to the wall framing and not the ceiling/attic space to see the joist/truss direction, then tightly spaced or deeper wall studs could be a sign that it is load-bearing since a heavily loaded wall would require more studs and a larger stud area to resist the applied loads.
Floor joists that frame into an exterior wall will need to be supported at the opposite end by a bearing wall or beam. The joist span depends on the wood species/grade, applied load and joist depth/spacing but a good rule of thumb would be that a joist will span between 10 and 20 feet (3 and 6 m). So if a wall is a distance away from an exterior wall that is within this range then there is a better chance that it is bearing compared to a wall that is only a few feet away from the exterior wall. Roof trusses can span much longer distances than joists, so if you have a gable roof there is a good chance that it can span between exterior walls and not require an interior bearing wall for support. This means that at the top floor of a house, the interior walls may not be supporting the weight of the roof structure and the weight of snow. For an idea of the standard spans for roof trusses given the snow load, truss member pitch, size and spacing, click here.
How to Remove a Load Bearing Wall?
Now that you know how to determine if a wall is load-bearing, you may be wondering what is required if you are wanting to remove one.
When removing a bearing wall in a residential home, a beam or lintel is required to replace the wall and carry the load to each side of the opening. A beam can either be dropped and have the floor joists sit on top of it, or the beam can be in the same plane as the joists having the joists frame into the side of the beam.
Flush framing joists into the side of the beam is a more expensive option as it can involve cutting the joists and installing joist hangers at the ends of the joists. This option, however, can eliminate the need for a bulkhead that would be required if the beam was dropped, which leads to a cleaner look. The size of the beam and posts required is a function of the amount of weight that the beam will support and the width of the opening. Sometimes, installing a beam and posts may not be all that is required when removing a bearing wall. The structure below the bearing wall will need to be looked at as well. If there is a bearing wall below, a post will need to be added to continue the load down to the foundation. If there is a beam below, it may need to be reinforced depending on where the post is located along the span of the beam.
But wait, there’s more… The foundation needs to be assessed to make sure it can handle any additional loading that may be introduced as adding an opening in a bearing wall alters the load path. If the foundation cannot handle the increased load, reinforcing of/or adding to the foundation will be required which can be very messy and costly.
It is critical to shore the floor joists prior to removing the wall. Shoring in this case involves temporarily supporting the weight of the floor structure that was originally intended to be supported by the wall being removed. This can be done by installing temporary beams and posts (shown on the left), or by building a temporary stud wall.
If a bearing wall is removed without installing shoring beforehand, this could lead to a collapse of the structure and would create a safety hazard.
Most jurisdictions require permits for the removal of a bearing wall, so If you are wanting to remove a wall in your home, it is highly recommended to consult with a professional structural engineer. But now that you know which walls could be bearing and what is involved in their removal, it will hopefully help you in the planning and budgeting stage of your next home renovation project. If you have any questions or comments on the content, feel free to leave a message in the comment section below!
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I have been wondering if I can remove a wall in my kitchen. It is good to know that I will want to check if there are any joints sitting on the frame. It might also be smart for me to inspect if the roof trusses would lose support by removing the wall. I might want to get a contractor to help me figure out if I can remove the wall.
wow, Noah, that’s a great article and helped me or you can increase my knowledge on wall bearing.
Your article along with this article
https://www.buildingsolutionpk.com/cost-to-remove-load-bearing-wall/
has really helped me.
Kiddos to you both.
I have a situation where I want to remove a closet that is next to a furnace that are side by side in the middle of my small home. I have already done one remodel, removing a wall between a bedroom and kitchen. I remember the contractor had to add a giant beam up in the ceiling where the old wall was. Now I want to extend that, so I would imagine another beam for load bearing will have to be done. The wall that goes the opposite direction, will it need a beam as well?? How can I tell without ripping the wall out, myself? I am pretty good at ripping drywall out, that’s for sure! Should I just go for it? Or have my contractor tell me my dreams aren’t gonna happen???
Hi Peggy. Thanks for the post. The best way to tell if a wall is load bearing is to go in the attic/ceiling space to see if there is any framing (joists/rafers/trusses) supported by that wall. If it is a small home, usually roof framing is in one direction only (North/South or East/West).
Hey Noah,
Your article is very impressive I must say This is going to help me in removing load bearing walls of house.
Thanks
My house has a truss roof. The trusses run from front to back. I assume that means that the front and back exterior walls are holding up the trusses and are load bearing. I wonder about the exterior walls on the sides that run parallel to the trusses? My house has a brick exterior and wooden stud exterior walls. I would like to run an exhaust fan from my microwave/range hood directly out through the exterior side wall of the house. There is a stud in the way (of course). I would like to cut the stud out of the way to make room for the vent duct. I would not be removing the wall, just cutting one stud. I am able to get into the attic and inspect the area at the top of the wall. Thanks for any advice!
Hi Noah,
Your article on load bearing walls was very informative, I never thought about the foundation so I'm glad I read it.
Our home was built in 1955 and removing load bearing walls in our home is something we would like to do in the future so we're able to have that open concept main floor and basement as much as possible.
Having an engineer visit our home to tell us what we can and cannot do would be ideal. Not sure if Crosier Kilgour & Partners works with residential renovation clients or if they only work with commercial clients?
Thank You.
Excellent article. I do have a question regarding the widening of an opening in a wall and if it is load bearing or not. I looked in the attic and they appear to be engineered trusses and the wall with the opening is running below these. The wall in question is not directly over the steel beam that runs the length of the basement, and appears to be 18in to 24in; off to the side of this.
Based on this, I assume it is not a load bearing and could be opened up… do you agree or is there something else to check.
Look forward to hearing from you.
Nick. Winnipeg.
Hi Nick. Thanks for your interest in the article. Bearing walls don’t always line up with the beams supporting the main floor. Sometimes they are slightly offset from the beam and sit directly on the floor joists. I would hire a structural engineer to confirm if this wall is bearing or not. Feel free to reach out to me at info@structuralengineeringbasics.com if you have any more questions.
Noah