Why foundation cracks in your home shouldn’t be ignored

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Homeowners and home buyers may not notice a small crack in their foundation, but that tiny flaw could lead to serious problems if it’s not addressed. While every homeowner would certainly be aware of a major flood in their home, any penetration of water into a home has the potential to create an issue for the property and the people in it.

We asked two specialists for advice: Scott Reid, an exterior home expert at Angi, a home-services company formed by the merger of Angie’s List and HomeAdvisor, and Tim Tracy, a corporate sales trainer with Groundworks Companies, a national foundation services company based in Virginia Beach. They responded via email and their comments were edited.

Q: Why is water penetration in a foundation so dangerous for a home?

Reid: Water penetration in a foundation is a common issue that can cause cracks, bowed walls and uneven or sagging floors in your home. Water that creates bug infestations, mold and musty odors can also shift your foundation, causing doors or windows to get stuck or stop opening and closing easily. While some of these issues are annoying, others can pose real risks to you and your home. Bowing can cause walls to separate and weaken your home’s structural integrity. Cracks can lead to standing water, constant moisture or potential floods that can invite black mold, which is a major health risk for anyone living in your home, particularly those suffering from respiratory conditions.

Tracy: Your foundation is more vulnerable to damage than you might think. If you live in an area that sees heavy precipitation, your home may readily fall victim to the effects of hydrostatic pressure. Hydrostatic pressure forces the materials supporting your foundation to rapidly expand and contract. To compensate for those rapid changes in size, your foundation can crack, allowing unwanted moisture into your home. That moisture can cause your home to settle prematurely, to sink at an unusually quick rate or to otherwise crack and fail to support your home.

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If you think something may be wrong in your home, you’ll want to conduct an inspection or reach out to professionals in your area for guidance.

While exploring your basement or crawl space for foundation water damage, you’ll want to keep an eye out for:

Musty smells. The more moisture makes its way into your home, the worse your crawl space or basement is going to smell. These unpleasant smells crop up as that moisture makes its way into your home’s more porous materials, including your furniture, wooden supports and drywall. If it turns out that you do have a leak on your hands, you’ll not only need to see that leak patched but also any materials that took on water damage replaced as soon as possible.

Mold clusters. While mold spores don’t enter your home with unwanted moisture, they will take advantage of its presence. Mold growths in your basement or crawl space often indicate the location of a foundation leak. Do not try to remove mold from your home without professional guidance. At a minimum, you should have safety materials, like gloves and a mask, on hand if you want to try to remove these clusters from your home.

Popping floor joists. Your floor joists help keep the upper floors of your home in place. If your home is suffering from foundation damage, these joists can begin to either rot or rust. In turn, they can weaken your floors and cause them to sag, bounce or otherwise become unsafe to walk on.

Bowing walls. Much like your floors, your walls can start to pull away from their structural supports if exposed to excessive moisture or standing water. Keep a wary eye out for bowing walls, gaps between your wall and the floor or for drywall that looks unstable to the touch.

Q: What are the prime reasons a foundation gets damaged by water?

Reid: Water damage can be traced back to many different sources. Plumbing and gutter leaks, clogged drains, cracks in floors and windows, and condensation on basement walls should quickly alert you to a problem; while a shifting foundation, deteriorating sewer line, worn waterproofing, broken sump pump and poor initial foundation design can all remain hidden for some time.

Where you live also influences your home’s susceptibility to water damage. If your home is downslope from the land around it, water will naturally flow toward your home instead of away from it. Homes near water — like a river, lake or ocean — are also more likely to experience water damage in their foundation or basement. And last, areas that get hit by heavy rainfall or frequent storms are more prone to experience water damage, as they simply must deal with more water more frequently.

Q: Does homeowner’s insurance cover those costs? Or flood insurance?

Reid: Who covers the costs of water damage will depend on what caused the damage in the first place. Homeowner’s insurance should cover water damage if it’s caused by unexpected issues with appliances or fixtures, but most policies do not cover damage caused by other things like sewer backups, natural disasters or floods.

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Flood insurance is a separate policy from homeowner’s insurance and your options and costs will depend primarily on where you live and whether your home is in a high-risk flood zone. You’ll get this policy either through the National Flood Insurance Program policies in certain areas or certain private insurers. If you’re in a high-risk area, you were likely required to purchase flood insurance when you bought your home. Flood insurance will cover damage caused directly by flooding, but it’s important to talk to your agent about exactly what this means, because it can be confusing.

Tracy: When you apply for insurance, the underwriting process will assess the risk of your property. Many aspects of your home will be considered, including its location and construction, and the results will determine your eligibility and insurance rates.

Foundation and water problems are two of the biggest insurance risks, and if an inspector finds signs of damage, your home may be deemed uninsurable. This is why it is important to have a foundation expert do an inspection to help you prepare for insurers, learn about potential solutions and secure your home.

Q: What steps can homeowners take to prevent foundation damage?

Reid: Before a big storm hits, go over your foundation and plug any holes, fill in cracks in the walls, caulk windows, window wells and doors, and apply a waterproof coating to prevent moisture from sneaking in. If you’ve noticed water damage or flooding in the past, you may also want to consider investing in improved drainage and/or a sump pump to better handle pressure and runoff that come with heavy rains.

As you’re going over your foundation, if you find large holes or cracks, or it seems like the walls, ceilings or floors have already started to shift, bring in a local professional to look over the space and make recommendations on how best to repair and waterproof your foundation. It’s best to fix anything that has already started to shift and prevent any further damage from happening.

Tracy: To protect your home before a storm, take these steps:

Invest in a sump pump: They can remove more than 2,000 gallons of water per hour from your home during a storm. Buy a backup battery sump pump in addition to a standard sump pump in case the power goes out.

Inspect your gutters and drains: Make sure the gutters are not clogged. If they become clogged, you risk sending water straight from your roof down to your perimeter, where it can more readily put stress on your foundation.

Use smart water sensors: Sensors will alert you when water enters your home.

Install backflow drain valves: These valves protect your home if your sewer threatens to overflow.

Elevate your utilities and belongings: It’s always a good idea to keep your more important belongings off the ground during a storm, including your utility systems. Consider installing new shelving units to elevate these systems so they don’t short out in the middle of bad weather.

Install a flood vent to help take the pressure off your walls and foundation during the middle of a storm.

Invest in an interior drain: They are designed to keep your home dry and they intercept leaking water from the walls and floor, directing it to a sump pump system.

Install an exterior drain curtain: These curtains are often designed to resemble loose gravel and can be placed over your drain without obstructing it to prevent larger objects from clogging your drain.