House Jacks2026-11-02T14:57:10-06:00

Fix Sagging Floors with House Jacks in [Target Location]

Sagging, uneven or bouncy floors often signal that the support system beneath your home needs attention. When crawl space support posts settle or floor framing weakens over time, the fix is more than simply lifting the floor; it means restoring long-term structural support.

House jacks, also called crawl space jacks or floor support jacks, are engineered to strengthen and stabilize your home's floor support system. At NV Waterproofing and Foundation Repair, every repair begins with a thorough structural inspection to pinpoint what's causing the problem. From there, we'll recommend a customized floor stabilization solution built to support weakened floor joists, reinforce your crawl space and help protect your home for years to come.

What Are House Jacks?

House jacks are adjustable steel support posts designed to stabilize sagging floors by reinforcing weakened floor joists and beams from beneath your home. Installed in a crawl space or basement, they transfer structural loads to a stable foundation beneath your home.

Unlike temporary jack posts or wood supports, engineered house jacks serve as a long-term structural repair. They help reduce floor movement, improve stability and, in many cases, lift sagging floors closer to their original position.

Every home is different, which is why the right repair starts with a thorough inspection. We'll assess your floor framing, crawl space conditions and structural supports to determine whether house jacks are the best solution for your home.

What Causes Crawl Space Structural Damage?

Crawl space structural damage usually develops gradually as moisture, shifting soils and aging materials weaken the floor support system beneath your home. Excess humidity, poor drainage, freeze-thaw cycles and older vented crawl spaces can all contribute to wood deterioration, settling support posts and unstable soil. Over time, these conditions may leave floor joists and beams without adequate support, resulting in sagging, uneven or bouncy floors.

Our Crawl Space Support Solution

Every sagging floor has an underlying cause, so every repair begins with a thorough structural inspection. If weakened floor supports are the source of the problem, we’ll recommend a permanent solution designed to stabilize your home’s floor system for the long term.

  • For stabilizing crawl spaces and sagging floors

    SmartJack® House Jack System

    The SmartJack® House Jack System is NV Waterproofing and Foundation Repair‘s engineered solution for stabilizing sagging floors and strengthening weakened crawl space support systems. Adjustable galvanized steel support posts are installed on a stable base to deliver permanent support beneath floor joists and beams, helping reduce floor movement while improving floor levelness.

    Every home is unique, which is why every SmartJack® installation starts with a comprehensive structural inspection. We’ll evaluate your crawl space, floor framing and support system to determine the right placement and number of supports needed for lasting performance. The result is a repair that’s designed specifically for your home’s needs, not a one-size-fits-all fix.

    • Stabilizes sagging and uneven floors permanently
    • Reinforces weakened floor joists and beams
    • Adjustable design helps improve floor levelness
    • Heavy-duty galvanized steel stands up to corrosion
    • Installed on a stable, engineered base
    • Tailored to your home’s structural needs
    • Backed by NV Waterproofing and Foundation Repair‘s written warranty
How It Works

Our SmartJack® Installation Process

Here’s how we inspect, design and install a customized SmartJack® support system to stabilize sagging floors and strengthen your home’s crawl space.

Symptoms

Signs Your Home Could Need a SmartJack® System

Sagging floors rarely get better on their own. If you’re noticing changes in how your floors feel or other signs of structural movement, your crawl space support system may need attention. A professional inspection identifies the underlying cause and determines whether SmartJack® is the right solution.

Common Signs Include:

  • Floors that sag or slope
  • Floors that feel bouncy underfoot
  • Floors that feel soft or unstable
  • Squeaky floors that are getting worse
  • Gaps forming between floors and baseboards
  • Crawl space support posts that are leaning, rotting or failing
Benefits

Why choose the team at NV Waterproofing and Foundation Repair for foundation piers

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What To Expect

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An expert will inspect the problem area and surrounding conditions, including soil movement, drainage, structural integrity, and any related concerns.

Clear explanation
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We’ll walk you through what we’re seeing in easy-to-understand language so you know the root cause of the issue, not just the symptoms.

Review recommendations

If repairs are needed, we’ll outline your options, pricing, and timeline so you can make the best decision for your home.

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Before & after photos

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    After assessing the situation, we replaced their old sump pump with a state-of-the-art TripleSafe Sump Pump system. This advanced system includes three levels of protection: a primary pump, a secondary pump for heavy water flow, and a battery backup to ensure the basement stays dry even during power outages. The homeowner now has peace of mind knowing their basement is fully protected, no matter the weather.

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    Seeking an effective solution, the homeowner reached out to our team for a professional assessment. We identified the main cause of settlement: soil erosion under the slabs—a common issue in Manassas due to its clay-rich ground and fluctuating moisture. To address both the immediate hazards and prevent future damage, we recommended our two-part approach: the cutting-edge PolyLevel® concrete leveling system and NexusPro® Joint Sealant.

    The repair process began with drilling small holes into the affected concrete slabs, allowing us to inject high-strength PolyLevel® polyurethane foam beneath the surface. As the foam expanded, it filled voids, stabilized the soil, and gently lifted the slabs back to their original positions. The process was quick, clean, and minimized disruption, giving the pool deck a level, safe surface once again. PolyLevel® foam is waterproof and lightweight, reducing the risk of future settling and ensuring long-term durability, even in a wet poolside environment.

    To provide further protection, we sealed all cracks and joints with NexusPro® Joint Sealant. This flexible, weather-resistant sealant prevents water from seeping beneath the slabs, protecting the soil and concrete from additional erosion. The result was a clean, finished appearance that not only improved the look of the deck but also safeguarded it for years to come.

    Thanks to modern concrete leveling technology, the homeowner’s pool deck was transformed from a liability into a safe and attractive outdoor gathering space. The project was completed in a single day, with minimal mess and immediate results, giving the homeowner peace of mind and renewed pride in their backyard. If you’re facing similar issues with your pool deck in Manassas, VA, the PolyLevel® system and NexusPro® Joint Sealant offer a fast, effective, and lasting

Our service area

Proudly Serving Northern Virginia, D.C., and Suburban Maryland

Frequently Asked Questions

How much do house jacks cost? 2026-10-02T09:45:48-05:00

The cost of installing house jacks varies based on the size of your home, the number of supports needed, crawl space accessibility and existing structural conditions. Because every repair is customized, there’s no one-size-fits-all price. A free professional inspection lets us provide an accurate recommendation and estimate for your home. 

How do I know if my home needs house jacks or another repair solution? 2026-10-02T09:45:21-05:00

The only reliable way to know is through a professional structural inspection. Sagging or uneven floors can result from several issues, including weakened floor framing, failing support posts, foundation settlement or moisture damage. We’ll pinpoint the root cause and recommend the repair that’s best suited for your home, not simply install a product. 

Will house jacks continue to be adjusted over time? 2026-10-02T09:44:55-05:00

SmartJack® support posts are adjustable, which allows for precise installation and, if needed, minor future adjustments. Depending on your home’s condition and repair plan, we may recommend additional adjustments as the structure settles and responds to the new support system. 

How long does house jack installation take? 2026-10-02T09:44:27-05:00

Most house jack installations wrap up in one to two days, though larger or more complex projects may take longer. Your timeline depends on the size of the crawl space, accessibility, the number of supports required and whether additional structural repairs are needed. Your inspector will walk you through what to expect before work begins. 

Can house jacks level uneven floors? 2026-10-02T09:43:59-05:00

In many cases, yes. House jacks can help lift and stabilize sagging floors, improving floor levelness and reducing bounce. However, every home is different, and the amount of correction depends on factors such as the condition of the framing, how long the floors have been sagging and the home’s overall structural condition. 

Are house jacks a permanent solution? 2026-10-02T09:43:26-05:00

Yes, when installed correctly. Professionally installed house jacks are built as a long-term structural repair, not a temporary fix. When installed on a properly prepared base and paired with the right repair plan, they provide lasting support for weakened floor systems while addressing the underlying cause of the problem. 

How do house jacks fix sagging floors? 2026-10-02T09:42:40-05:00

House jacks stabilize sagging floors by transferring the load of your home’s floor system to a stable, engineered base beneath the crawl space. This added support reinforces weakened joists and beams, helping reduce floor movement and, in many cases, improving floor levelness. Each system is customized to your home’s specific structural needs. 

What are house jacks? 2026-10-02T09:41:53-05:00

House jacks are adjustable steel support posts engineered to reinforce weakened floor joists and beams from beneath your home. Installed in a crawl space or basement, they deliver permanent structural support where existing supports have settled or deteriorated. Professionally engineered house jacks help stabilize sagging floors and shore up your home’s floor system for long-term performance. 

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Service Areas

NV Waterproofing has locations throughout Northern Virginia, D.C., and Suburban Maryland.

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At NV Waterproofing, we pride ourselves on providing permanent solutions, and stand behind our work with industry-leading, fully transferable warranties and guarantnees.

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