Often when considering a renovation, homeowners wonder if a particular wall in their home is a structural load-bearing wall or not. When you are still in the early planning stage of your project, it would be prudent to consider the possibility that your wall is load-bearing. It is an important thing to know because if it isn't load-bearing, then removal can be fairly straight forward and not particularly costly. On the other hand, removal of a structural load-bearing wall, while often possible, will require structural changes such as installing a beam, columns or wall reinforcement in order to transfer the load from the wall to other structural elements. Needless to say, if you decide to remove a load-bearing wall you will need to plan for additional costs and seek professional advice.
Caveat: this information is intended to guide homeowners living in a typical newer, professionally built, North American style wood frame house. If your home is very old and/or has been subject to numerous additions and alterations over the years, or is built from other less-common materials, this information should still be helpful, but you may have an unusual existing structural condition beyond the scope of this article.
So then, how can one tell if a wall is load-bearing or not. First, let's agree on what the phrase "load-bearing" means. Simply put, it means "it is responsible for carrying the weight (load) of any other part of the house other than itself" Anything that is not bolted down or fixed to the building does not count, such as furniture, appliances, etc.
Structural engineers generally define the following types of building "loads":
The "dead load" is the total weight of all the structural components, the fixtures and permanently attached equipment of a building, including its foundations.
The "live load" is the weight that is superimposed on the structural components of a building by the use and occupancy of the building such as furniture, appliances and people (and the activities of people). This will be different for different rooms. For example, your living room (unless it's on a concrete slab on grade) is probably not designed to carry the weight of your car, while the garage floor is.
There is also a "snow load" that engineers take into account in certain regions. The snow load is stipulated by the local building code and ensures that the roof structure is capable of carrying the weight of snow in addition to its own "dead load".
Your house will have been designed to carry its own dead load, the anticipated live load, and perhaps a snow load of some kind.
So back to the original question. It may seem like common sense, but it pays to remember that buildings are built from the ground up. Starting with the footings and foundation, then the first floor level, first floor walls, second floor level, second floor walls and then the roof (or some variation of this depending on the configuration of the house). Load-bearing structural elements carry, in addition to their own weight, the weight (dead load) of something above it. Which is where you need to look things such as:
Floor joists from the floor above
A wall above
Roof trusses above
A column above
1. Floor joists from the floor above. If there is a floor above the wall you want to remove, you will need to uncover the floor joists above the wall (either from above or below) and determine if any of the joists bear on the wall you want to remove. This can be determined by a visual inspection. Do the joists appear to end at, and rest on, the wall? Or do you see a longer joist running the over wall and ending further away at another (possibly exterior) wall? If the joists end on the wall you want to remove, then your wall is definitely load-bearing.
2. Wall above. Is there a wall located directly above the wall you want to remove, on the floor above? If there is, then your wall is almost certainly load-bearing. To determine this without doing any demolition, simply locate the walls by measuring from common elements on each floor such as a stairway opening or exterior wall.
3. Roof trusses above. If the wall you want to remove is on the top floor of your house, with only the roof or unoccupied attic space above, you will need to verify if it is helping to support any part of the roof structure. If your roof structure is made from factory manufactured roof trusses as most modern roofs are, it will likely bear on your exterior walls. Or your roof could be stick-built, meaning completely cut and constructed piece by piece on site. Either way, it is possible that the wall you want to remove contributes, in some way, to carrying part of the weight of your roof. To determine if this is the case, you will need to get into the attic space and locate the wall below. Similar to items 1 and 2 above, is there anything bearing on your wall, such as ceiling joists, columns or a wall within the attic space? If not, then your wall is probably not load-bearing.
4. Column above. If there is a column bearing on your wall, then there should be a column buried in the wall you want to remove, and the load of that column should be transferred to a column under it right down to the foundation. If this is the case, you may be able to remove the wall, but not the column embedded within the wall.
Also consider the possibility that the wall you want to remove contains plumbing pipes, ductwork (especially return ducts or small vents), or electrical wiring that may need to be rerouted. There items alone could make removing the wall more hassle than its worth.
These are some of the more common conditions to look for when evaluating the load bearing possibility of any wall being considered for removal. This should be done early in your project while you are in the planning stage. If you find out that your wall is load bearing, you will need to be creative and find another way to achieve what you are looking for, or else consult an expert and plan for additional costs. It is always possible to work within the structural limitations we have been given, so I encourage you to consider other ways to achieve the result you want. Oftentimes, when we are forced to rethink our original idea, we come up with a better, more economical and easy to construct solution.
This advice is intended as a general guide only and cannot substitute for an in-person visual inspection of your home. Prior to beginning any demolition you must satisfy yourself as to the structural design of your home. If you are uncertain about the particular condition of your house, please consult an expert such as architect, engineer or an experienced and qualified house framer.
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