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Signs Your Home Might Need Crawl Space Support Posts

Table of Contents

1. What Is A Crawl Space?
2. What Are Crawl Space Support Posts?
3. What Causes Floors Above A Crawl Space To Sag?
4. Signs Your Crawl Space Might Have A Problem
5. Crawl Space Repair Options
6. How To Prevent Problems In Your Home’s Crawl Space

Searching for information about crawl space support posts? If so, you’ve landed on the right page because that’s what we’re going to review in this article. You’ll learn what crawl space support posts are, why the floors above crawl spaces sometimes sag, signs your crawl space might need support posts, repair options, and more.

What Is A Crawl Space?

In a house with a crawl space foundation, the crawl space is the area – from 1.5-3 feet high – under the house. It’s just big enough to crawl around in but not stand up. Crawl space foundations have been popular for decades because they provide easy access to plumbing, electrical wiring, and HVAC systems.

What Are Crawl Space Support Posts?

Crawl space support posts (also called piers) are vertical columns – generally made of steel, wood, or concrete – that support houses with crawl spaces. Crawl space support posts hold up the girders (also called beams), and the girders hold up the floor joists. The crawl space support posts are installed vertically, perpendicular to the ground, and strategically located throughout the crawl space area. The entire structure supports the weight of the main floor. However, crawl space support posts can weaken over time for various reasons.

What Causes Floors Above A Crawl Space To Sag?

Floors above crawl spaces can sag for various reasons, including the following:

  • The crawl space support posts have settled – If the dirt floor in the crawl space is soggy, the crawl space support posts can settle into the ground and become non-vertical. The sogginess might be caused by a high groundwater table, rainwater leaking into the crawl space or a plumbing leak.
  • Damage from termites or other wood-eating pests – A crawl space is the perfect environment for termites and other wood-eating pests. As they eat away at the wooden structures in the crawl space, the floors above can weaken and sag.
  • Moisture in the crawl space – Open crawl space vents allow warm, humid air to flow in and condense on cooler surfaces. This can lead to excessive moisture buildup and wood rot, eventually weakening the wooden structures in the crawl space and causing the floor to sag.
  • The floor joists aren’t big enough – If the floor joists aren’t big enough for the distance they span, the floor will eventually start to sag.
  • There aren’t enough crawl space support posts – Sometimes, there are an insufficient number of support posts in the crawl space.

Signs Your Crawl Space Might Have A Problem

Signs you might have a problem in your crawl space include the following:

  • Sagging floors – One of the most apparent signs of a problem in your crawl space is sagging floors. They might bounce when you walk on them. Furniture might even shake when you walk by.
  • Cracks in the walls – If you notice cracks in the walls of your home, it could be a sign there’s a problem in your crawl space. The cracks occur when the weakened foundation exerts pressure on the walls, causing them to crack.
  • Musty odors – Some of the air from the crawl space flows into your home’s living area; if the crawl space is full of mold, you will smell it.
  • Standing water – Standing water in the crawl space indicates a drainage problem. This can lead to mold growth and, as we’ve noted above, can cause issues like settled support posts.
  • Visible damage – Sometimes, the damage to your crawl space is visible. This indicates the issue has progressed significantly.

For more information, see Repairing A Crawl Space Foundation.

Crawl Space Repair Options

The chosen crawl space repair option will, of course, depend on the specific problem:

Check out our Crawl Space Foundation Repair Video!

  • Replace the settled support posts – If the support posts have settled, they can be replaced. However, if they settled because the ground was soggy, this must be remedied so the new support posts don’t suffer the same fate. We’ll talk about how to prevent crawl space problems in just a bit.
  • Replace the deteriorated screw jacks – Over time, screw jacks can become corroded, causing them to be less effective or even fail. The solution is replacing them with screw jacks with an anti-corrosive coating. If the screw jacks became corroded because of excess moisture in the crawl space, this must be fixed.

Additional crawl space repair options can include replacing damaged insulation and encapsulating the crawl space. Encapsulating the crawl space is the best way to prevent problems.

Check out our Crawl Space Beam, Girder, and Problems and How to Repair!

How To Prevent Problems In Your Home’s Crawl Space

Because most crawl space problems are caused by excess moisture, the best way to prevent trouble is to get groundwater around the foundation under control. Here are some ways to do that:

  • Re-grade the yard around your home – Re-grading the yard ensures groundwater will drain away from the house and not toward the foundation.
  • Clean gutters regularly – Gutters are designed to collect rainwater and direct it away from your home’s foundation. However, if gutters become clogged with leaves and debris, they won’t be able to do their job correctly. This can result in water accumulating around your foundation, leading to foundation issues.
  • Use downspout extensions – These extensions attach to your downspouts, taking water several feet away from the foundation before release. The typical length for a downspout extension is around six feet, though some are even longer.
  • Keep trees away from the foundation – Trees can be a beautiful addition to your yard. However, they can cause significant foundation damage. The roots of trees can penetrate the foundation, causing it to become unsteady. Trees too close to your home should be removed or transferred to another location to prevent damage.
  • Install a drain tile system – Installing a drain tile system is an excellent solution for preventing foundation problems. A drain tile system consists of a perforated drainage pipe installed around the perimeter of the foundation at the footing level. The drainage pipe is connected to a sump pump that pumps water out and away from your home. The drain tile system is very effective in preventing the accumulation of water around your home’s foundation.

If you think your home might have a problem with the crawl space support posts, contact Bay Area Underpinning today to schedule a crawl space evaluation and receive a repair estimate.

Steve Egloff

Steve Egloff

Founder of Bay Area Underpinning

Steve is the Founder of Bay Area Underpinning, a foundation repair company serving the San Fransisco Bay Area, California. Bay Area Underpinning was founded in 2005 with the goal of providing a cost-effective, engineered solution to foundation settlement problems with an emphasis on educating customers to make them feel comfortable with the various methods of foundation repair.

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