Will Sistering a Floor Joist Help with Uneven Floors?

When the floor joists in a home have problems, sistering them is a popular solution. However, if your floor is uneven, sistering the problematic joist shouldn’t be the only solution. 

What Sistering Does 

Sistering a floor joist refers to the act of attaching a healthy wooden beam to the failing floor joist. This can be done by nailing the pieces of wood together or by using an adhesive. The idea behind sistering a floor joist is to provide the failing joist with support from a healthy piece that is capable of supporting more weight than the original joist. This avoids having to replace the original floor joist while also preventing it from deteriorating further. 

Sistering a floor joist is one of the most popular floor joist repair solutions among homeowners because it’s something many can do themselves. All that is needed is a wooden beam, a strong adhesive, or some nails. Despite the popularity of the method, sistering a floor joist will not help you even out your floor. This is because the method focuses on temporary stabilization instead of leveling. 

Why Sistering Doesn’t Help 

Sistering a floor joist is a good way to temporarily provide the joist with some stability. After sistering, however, your floor will remain uneven because this solution fails to address the problem at hand. It’s a temporary solution because the healthy beam will eventually begin to fail like the original one after some time. This solution also fails to actually lift the floor back to its original position, so it’s not a good method to use on its own if your floors are uneven. 

In order to permanently stabilize your floor and lift it so that it’s back to its original position, structural support jacks must be used. Structural support jacks are made of steel, so they will not deteriorate the same way a wooden beam would. Apart from their longevity, support jacks are capable of lifting the floor so that it can be even once more.