Floor Joist Support in a Crawl Space

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Though you don’t likely think about them on a daily basis, the structural integrity of the floor above your home’s crawl space depends on the joists that support it from below. Unfortunately, there are many instances in which crawl space floor joists need more support in order to continue functioning properly. In this article, we’ll cover the basics of floor joists, the reasons they fail, and some of the ways to add support to your joists to ensure they remain intact.

What is a Floor Joist?

Before we go any further, let’s ensure that you have a clear idea of what a floor joist is. Simply put, a joist is nothing more than a piece of lumber that is typically about two inches wide with a variable length. Most standard floors consist of a series of joists that run parallel to one another.

If you notice the floor above your crawl space is sagging, it may be because your joists need support. Read here to learn why this happens and how to fix it.

The flooring you walk on rests on top of the joists and depends on them for support. The joists themselves rest on beams, which are typically thicker and run perpendicular to the joists. This construction method is incredibly reliable, which is why it is so common. However, as the next section will show, there are plenty of issues that can go wrong with floor joists.

Why Crawl Space Floor Joists Fail

In anticipation of our discussion of the best ways to provide additional support to crawl space floor joists, let’s cover some of the main ways that these structural elements can fail. Below is a list of some of the most common causes of floor joist failure:

  • Rot: Over time, moisture can permeate the lumber that comprises your floor’s structure, causing it to rot. Once rot has begun, your joists will quickly lose their structural integrity.
  • Inadequate structural material: At times, there is nothing wrong with your joists at all. Instead, the issue is that there are not enough joists, or they are spaced too far apart from one another to be effective.
  • Settling and shifting soils: Shifting soils and uneven settling can cause a wide range of issues for your crawl space and the rest of your home. At times, those issues include compromising the ability of your joists to support the floor above.

For many homeowners, it can be quite difficult to determine the cause of their joist failure on their own. A better approach is to seek the support of a crawl space expert in your area who can accurately diagnose your problem and lead you toward the solution that is best for you.

Reinforcing Floor Joists

Now that the basics of floor joists and their main reasons for failure are out of the way, it’s time to dive into the main ways to resolve this issue. Remember, reinforcing floor joists is something that a professional should take care of. However, it can help you to understand some of the tactics that those professionals may use, many of which we have described in the sections below.

Add More Joists or Beams

Earlier, we mentioned that one of the reasons floor joists can fail is that there are simply not enough of them. Sometimes, the simplest solution for this problem is to install additional joists in the spaces between your existing joists. Adding these joists boosts the overall strength and rigidity of your floor and may be the quickest way to remedy any sagging or sloping you notice.

Similarly, we also mentioned that your floor joists rest on larger beams. There are cases in which the amount of flooring beams in your crawl space is simply not enough. Adding more beams is another straightforward way to fix this problem and add strength to your floor.

Incorporate Cross Bridging

Another relatively quick fix for floor joists that need more support is to add cross-bridging. Cross bridging consists of small pieces of wood that form an X shape between your joists, connecting one joist to another. Typically, a contractor will add cross-bridging to every space between your joists to ensure they are all equally capable of providing structural support.

If you notice the floor above your crawl space is sagging, it may be because your joists need support. Read here to learn why this happens and how to fix it.

Build Support Columns

Before we mentioned that your floor rests on joists, which rest on beams, what we did not note is that the beams in your crawl space usually depend on some sort of support columns that connect them to the ground and are responsible for holding the weight of the rest of your home.

If there is an issue with one of these columns, or there simply are not enough of them, adding additional columns can be a great approach. Support columns often consist of concrete or masonry and are an effective way to strengthen and support your entire crawl space.

Support Your Crawl Space with Piers

When your crawl space joists begin to fail due to differential settlement, you’ll need to take immediate action to level and strengthen your foundation. Often, this involves excavation and the installation of piers. These piers come in several forms, but they all tend to serve the same purpose, which is to make your home level once again and hold it in place better than before.

Signs Your Joists Need More Support

Before we conclude this article, we thought it would be helpful to share some of the signs that your crawl space floor joists need more support. If you notice any of the indicators in the list below, there is a chance that your joists are in need of reinforcement:

  • Cracked or sunken floorboards
  • Sagging floors
  • Sloping floors
  • Cracks in your walls
  • Jammed doors
  • Stuck windows

Sign Your Joists Need More Support

The signs above don’t necessarily mean that your joists need support. Instead, each of them can point to a different structural problem with your home. The best way to find out what that problem is is to seek the assistance of an expert on the topic.

Find Professional Help for Your Joist Support

Any type of structural damage or inefficiency in your crawl space is nothing that you should allow to go unaddressed. Such issues worsen over time, which can lead to costly repairs.

If you are in the Eastern North Carolina area and you have worries about the structural integrity of your crawl space, reach out to our team at Regional Foundation & Crawl Space Repair. We are happy to answer any questions you may have and provide you with a free estimate for your crawl space.