Technical Papers

Stow, The Soil Under Your House Might Not Be As Solid As You Thought

Tuesday, June 30th, 2020 by Mary Lowe

Is Your Home on Solid Ground?

This isn’t a metaphorical question; we’re being quite literal here: is your home on solid ground? Your first reaction is probably, “Of course it is!” Your second reaction is probably, “What a dumb question!” And, you wouldn’t be alone. Most people assume their homes are built on what we’ve come to call “solid ground.” After all, who would build a home or any other structure on anything but?

The answer may surprise you. That’s because the soil under and around our homes is often not as stable as we might think. In fact, the ground beneath your home is actually made up of many different layers of soil, each with its own properties, such as moisture content, density, and material type (clay, sand, etc.). Over time, these layers can wash out, soften as they are wetted, or shrink as they dry out.

Softening Soil
Think about stepping into some mud. That mud “squishes” underneath the weight of your body, and you sink into it, right? The same thing happens — only on a much larger scale — when certain types of soil become saturated with rainwater or snowmelt and the massive weight of a home and its contents causes the entire structure to sink or settle. When this happens, it can cause a whole host of foundation problems throughout the house, including uneven floors, sticking doors and windows, and ceiling gaps.

Soil Washout
Sometimes a large quantity of water, either from a broken pipe or severe weather event, can cause portions of the soil beneath your home to wash out completely, leaving empty space that can’t support the weight of the structure above it. This, too, can cause the home’s foundation to settle and sink.

Shrinking Soil
Just as too much moisture can be a problem, too little moisture can also cause issues with your home’s foundation. During prolonged drought conditions, clay soils can dry out and shrink, leaving voids that are unable to support the weight of your home. As with moist or washed-out soil, this can also lead to foundation settlement.

Poor Fill Soil Compaction
When your neighborhood was created, the developer likely moved soil around, removing it from hilltops and placing it in valleys to create flat, buildable lots. That soil — known as fill soil — needs to be adequately compacted to support the weight of the homes built on it. If it isn’t, those structures can, over time, sink into this poorly compacted fill soil.

What About Your Concrete?

Your house isn’t the only thing on your property. Your driveway, patio, pool deck, sidewalk, and walkways — all made of heavy concrete slabs — can all suffer from issues relating to poor soil.

Concrete is amazing stuff. It’s strong, durable and can be made into just about anything. But it’s heavy. And if the soil underneath it can’t support its weight for any of the reasons mentioned above, it can settle, sink and crack. When that happens, it doesn’t just create an eyesore that potentially lowers your property’s value, it can also create serious tripping hazards that you could be liable for as the homeowner.

So, now that you know a little more about the “solid ground” beneath your home and its concrete, it might be wise to ensure that it’s stabilized permanently. A reputable foundation and concrete contractor can achieve this in a variety of ways, including employing piers and anchors for foundations and basements and polyurethane foam to lift and stabilize uneven concrete slabs.

But before any of that can happen, you need to have your home’s foundation and concrete inspected by someone who has the expertise and experience to identify potential issues and customize a solution to address them.