Load Bearing Walls: How Do You Tell Which Are Structural Walls

If you’ve done renovations to your home then chances are that you have considered moving a door or window or removing one of the internal walls. Removing some of the internal walls can really transform your home by creating a large and spacious living space out of a previously separated kitchen, lounge, dining room etc. Unfortunately, in houses and apartments, a number of the internal walls form an integral part of the structure of the house, called load bearing walls and removing them may compromise the integrity of the structure and ultimately lead to sections of walls or the roof collapsing.

Types of Internal Walls

Some internal walls are purely there to divide a room into smaller sections while others are load bearing. The dividing walls which do not support any load can safely be removed without any risk. Load bearing walls may be supporting the ceiling and roof, an upstairs wall, the floor above or all three of these. Before demolishing a wall, it is essential that you find out which of the walls are load bearing and which are not.

Non load bearing walls can be removed without any consideration for the surrounding walls and structure while load bearing walls need to be unloaded by supporting the above weight with props, additional supports and lintels will have to be installed and finally the wall may be removed.

How To Find Out If A Wall Is Load Bearing

Finding out if a wall is load bearing is not a simple as it may seem, it is almost impossible to determine from the outside of the wall whether it is load bearing. There are a number of tests one can do to determine whether a wall or section is load bearing and to determine its function.

You can start by taking the back end of a mallet or hammer and tapping along the section of the wall. If the wall sounds like it has hollow sections with dull sounding sections between them then the wall is most likely a stud partition made from timber and plasterboard. If this wall is non load bearing then it will be really easy to remove and can be taken down without risk of collapse. It is however difficult to determine as some older houses used the timber sections in these walls as structural supports for joists.

Non Continuous Walls

If the wall sounds solid when tapping it then it is probably a brick or building block wall. This in itself is not enough to determine whether it is loading bearing. To find out, you need to look at the section whether the wall goes into the ceiling. If you go into the roof, you should be able to see the top of the wall. If the wall is not supporting a wall above it, a concrete slab or a main truss in the roof then it is likely not a structural wall and you should be able to remove it without any risk. If the wall runs underneath the floor above it, lift some of the floor boards to see how the wall interacts with the floor, if it is not supporting the floor joists or slabs then it should be able to be removed. This is clear when the wall sits in between two floor joists without touching them.

Continuous Walls

If the wall runs up and into the room above it then it is most likely a structural load bearing wall. This doesn’t mean that it cannot be removed however some plan will need to be made, probably within the floor boards, to support the wall above.

Types of Supports

There are three primary supports which can be installed to take up the load which was placed on a structural wall.

Concrete Lintels

These come in a number of standard sizes and are made in a factory by encasing stressed steel wire in concrete to form a strong support.

Concrete Beams

These are the same as concrete lintels in concept but are much larger and usually made on site. Concrete is poured around steel reinforcing rods to create a strong beam.

Steel Joists

Steel joists which are usually in the form of an H or I, commonly known as I-beams are rolled out in a number of sizes and lengths to suite different spans and loads.

It is also important that when the above mentioned supports are installed, they are installed correctly so that the reinforcing rods and wires take up the strain correctly or these too will fail.

The size and type of support to use requires some level of expertise, there are calculations to be done and a number of considerations to take into account.

It is important to consult an expert in the form of an architect, surveyor or structural engineer before proceeding with the removal of any sections of wall in your home. They will be able to give you professional advice on the walls you are able to remove as well as the supports required where structural walls are involved. Do not attempt any structural modifications to your home before consulting an expert and finding out about your local regulations.

Cover Image: House Construction by Chris RubberDragon used under CC BY 2.0