How To Install Crawl Space Support Jacks: Fix Sagging Floors

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Crawl space floor support jacks are essential for stabilizing sagging or bouncy floors in crawl spaces, preventing further structural damage.

These jacks provide a cost-effective and reliable solution to reinforce your crawl space, ensuring your home’s overall stability.

To install crawl space support jacks for fixing a sagging or bouncy floor, assess the affected areas, create a stable base with concrete pads or blocks, and position jacks under sagging beams. Raise and level jacks for even weight distribution.

Installing crawl space floor support jacks

Stay tuned as I am going to share with you the step-by-step guide on crawl space support jack installation in detail.

What Is A Crawl Space?

A crawl space is a low, unfinished area beneath your home, typically ranging from 1 to 3 feet in height.

It serves as a buffer between your living space and the ground, providing access to essential home systems like plumbing, electrical wiring, and HVAC ducts.

Crawl spaces are prevalent in homes without basements and can be found in both older and newer constructions.

Learn how to prevent crawl space moisture issues and maintain a dry foundation with our guide on proper sump pump drainage system installation.

The Role of Floor Joists and Crawl Space Supports

Floor joists are horizontal beams that span the width of your home and provide structural support for the floors above.

They are essential for distributing the weight of your home evenly and preventing sagging or bouncing in your floors.

The Role of Floor Joists and Crawl Space Supports

Crawl space floor support jacks, also known as crawl space floor jacks, are crucial for reinforcing and stabilizing these floor joists.

Signs You Might Need Crawlspace Floor Support Jacks

  • Sagging Floors

Noticeable dips or slopes in your floors may indicate weakened floor joists in the crawl space.

  • Bouncy Floors

If your floors bounce excessively when you walk on them, it could be a sign of inadequate support.

  • Visible Cracks

Cracks in your walls or ceiling can result from floor joists shifting due to insufficient support.

  • Uneven or Sloping Floors

Floors that are not level may require additional support to prevent further settling.

  • Door or Window Misalignment

Difficulty opening or closing doors and windows may occur when the foundation settles unevenly.

  • Pest Infestations

Gaps in crawl space supports can allow pests to enter your home, necessitating repairs.

  • Musty Odors or Moisture

Dampness or musty smells in your crawl space indicate potential moisture issues that can weaken supports.

  • Increased Energy Bills

Poorly supported floors can lead to gaps, causing heat or cool air loss, resulting in higher energy bills.

  • Crawl Space Cracking

Visible cracks in the crawl space’s walls or supports may signal structural problems requiring attention.

  • Previous Foundation Repairs

If you’ve had foundation repairs in the past, it’s wise to monitor for any recurring issues that may warrant additional support.

Find out how a French drain system can complement your crawl space support jacks to effectively manage water drainage beneath your home.

Best Crawl Space Floor Support Jacks

1. Akron Adjustable Floor Jacks

I chose Akron Adjustable Floor Jacks for my crawl space project because of their reliability and durability.

These jacks provided a custom fit, ensuring that they snugly supported my floor joists without any lateral displacement.

Their deep-embossed top and bottom plates prevented any movement or sagging, offering the stability I needed.

The double carriage lock added an extra layer of safety, making them the ideal choice for both temporary and permanent support in my crawl space.

These jacks truly exceeded my expectations, providing peace of mind and structural stability throughout the project.

2. BISupply Support Beam Basement Jack Post

As a reliable alternative choice, you can also use the BISupply house jacks for your crawl space leveling needs.

Their impressive weight capacity of up to 9,700lb at any height extension gives peace of mind, ensuring stable support during renovations.

BISupply Support Beam Basement Jack Post

The adjustable design, ranging from 12 to 16 inches, allows you to customize the height with ease using the turning bar and screw bolt, making them a versatile choice for both home and industrial applications.

These jacks served as a dependable solution to secure weak floors, making them an excellent addition to your construction toolkit.

Ensure easy access for inspections and maintenance by installing a well-sealed crawl space access door – an important component of your crawl space improvement plan.

Bouncy And Sagging Floor Joist Repair: Crawl Space Support Jacks

Bouncy And Sagging Floor Joist Repair: Crawl Space Support Jacks

Over time, weakened floor joists lead to bouncy or sagging floors.

Repairing this issue requires the installation of additional support, often in the form of crawl space floor jacks. Here’s a step-by-step guide on how to do it:

Step 1: Gather Tools and Materials

Before you begin, gather the necessary tools and materials:



Step 2: Safety First

Put on your safety gear, including 3M Virtua CCS protective eyewear and 3M worktunes connect hearing protector. Safety is paramount when working in confined spaces.

Step 3: Evaluate the Situation

Inspect your crawl space to identify the areas with sagging or bouncing floors. Measure the distance between the existing floor joists to determine the size of the new joists you’ll need.

Step 4: Cut New Joists

Using a DEWALT 20V MAX 7-1/4-Inch circular saw, cut pressure-treated lumber to the appropriate length to replace or reinforce the weakened floor joists.

Cut New Joists

Ensure that the new joists match the dimensions of the existing ones.

Enhance your crawl space’s environment and protect against moisture-related problems by considering the benefits of a crawl space dehumidifier installation.

Step 5: Sister the Joists

Sistering involves attaching the new joists alongside the existing ones.

Place the new joists directly next to the weakened ones and secure them together with Gorilla heavy duty construction adhesive and Newborn 930-GTD drip-free caulking gun and 16D nail fasteners, or screws.

Sister the Joists

This process effectively doubles the strength of the floor joists, providing additional support.

Step 6: Place Crawl Space Floor Support Jacks

It’s imperative to position Akron crawl space floor support jacks strategically. They should be spaced approximately 6 feet apart and, crucially, at girder beam joints.

Place Crawl Space Floor Support Jacks

Girder beam joints are critical points in your crawl space’s structural framework, and placing jacks here ensures that both sides of the girder beam have support and are level – not a step up or down.

Place the jacks directly under the girder beams, supporting them evenly from both sides.

This strategic placement helps distribute the load evenly and prevents any unevenness or sagging in the floor above.

Go through the importance of a vapor barrier for dry crawl space – an essential element for long-term structural integrity.

Step 7: Secure Crawl Space Floor Support Jacks

Fasten the crawl space floor support jacks to the joists using nails or screws, ensuring a secure connection. Double-check the level of support and adjust the jacks as needed.

Step 8: Test the Support

Gently bounce on the repaired floor to ensure it no longer sags or feels bouncy.

Make further adjustments to the crawl space floor support jacks if necessary, fine-tuning their height for optimal support.

Step 9: Monitor Regularly

Periodically check the crawl space and floor joists for any signs of movement or damage. Make adjustments or repairs as needed to maintain structural integrity.

Find out if crawl space vents should be open or closed in winter.

Final Thoughts

By following this detailed guide on how to install crawl space support jacks to fix bouncy or sagging floor, you can effectively get rid of unevenness in your floors by providing the necessary support for your floor joists.

This ensures a sturdy and safe foundation for your home while maintaining a level and stable living space.

Regular maintenance and inspections will help prevent future issues and preserve the structural integrity of your crawl space.

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