Mine subsidence can damage your home’s foundation, leaving you with big repair bills, unsafe property, and the need to find other shelter for your family. While early detection can help professionals protect your home’s foundation, too many homeowners don’t know how to recognize mine subsidence damage when it first starts to show its effects. Instead, it’s dismissed as settling, superficial wear due to the property’s aging, or otherwise dismissed or treated as a low-priority issue. Subsidence damage compounds over time, and many owners don’t even know their home is at risk. Too often, by the time a homeowner understands they need professional foundation help, the damage has escalated to the point where their property is in imminent danger of serious structural failure.
Welcome To Mining Country
When something subsides, it drops to a lower level. Headaches, inflation, and blood pressure are all things you want to subside. Your property’s land is nowhere on the list. Mine subsidence happens when the land underneath your property begins to sink due to former mining activity. Unlike landslides which result from sloping, subsidence causes vertical movement as the earth drops to fill in voids created during exploration and active mining operations. This is especially true with “pillar and room” mines which were popular in coal country.
With this style of mining, rooms are carved from rock and coal is removed with high-carbon coal pillars left intact to support the roof of the mine. While this was considered safe enough to keep the mine going from room to room, excavating as the workers went, it isn’t a structurally stable support indefinitely. Eventually, these pillars or the walls of the rooms collapse, creating a void that gravity seeks to fill, shifting the land’s elevation by eight feet or more. While some mines were buttressed with man-made supports, the Earth is undefeated when it comes to reclaiming its space, and most experts agree that these mines will eventually collapse, whether this year or 100 years from now.
Other mining practices, like “long-wall mining,” uses machines to pull out an entire seam of coal in a deep mine that’s hundreds of feet underground. When the coal and machinery are withdrawn, the mine collapses. Due to the depth of the mine, there’s no way to predict the amount of mine subsidence that will reach the surface, which is undeveloped at the time of mining. Years later, with property now built on ground that’s presumed settled and stable, the effects finally reach the surface.
To compound the severity of the issue, known mines that are potentially leading to mine subsidence are too unsafe to be properly surveyed and assessed to determine a potential timeline for disaster and plan for mitigation. In some cases, the mining company that sank a shaft is long out of business with no responsible party left overseeing their former sight of operation. Further, there are mine shafts for which no documentation survives, laying under the surface without property owners, realtors, or city planners being aware of the dangers as they consider new construction, property upgrades, or home sales to new owners.
Spotting The Signs Of Mining Subsidence
Before we get into the major indicators of mining subsidence damage, it’s important to note that early on, symptoms can appear that are attributable to a wide range of property issues. In many cases, the differentiating factor is the rapid development and worsening of the issue. While the land may naturally shift over time, subsidence from a mine collapse tends to move more earth faster, leading to greater stresses on the structures above the impacted area. While this still is not a sure sign that mine subsidence is to blame, in most cases, professional help will be needed to prevent further damage, whatever the root cause.
- Foundation and Basement Wall Cracks – Cracks in your foundation, basement walls, or garage floor are always something to keep an eye on. When they appear and start rapidly expanding day by day, there’s a major problem that needs to be addressed immediately.
- Deep and Continuous Cracks Around The Home – Long and deep cracks that keep going in straight lines indicate the land under your home is experiencing a significant amount of stress due to shifting to fill in empty spaces. It’s common to see smaller signs similar to this as the land rehydrates after an extended drought, but larger cracks in straight lines point to a larger space that’s filling in.
- Rapid Shifts In Window or Door Frame Alignments – As houses settle, it’s not uncommon for a door to stick a bit or a window to be tough to open. When multiple doors open and shut on their own, are wedged shut, won’t close, or windows are cracking and breaking on their own, it points to a more dramatic shift in your home’s foundation.
- Excessive Popping and Groaning From The Structure – Noises from older homes are common. If the frequency, severity, and volume suddenly increase, however, your property is trying to tell you something.
- Structural Separation From The Foundation – Mine subsidence can shift the stable land under your home, which was constructed to balance on the packed earth excavated by your home’s builder. As this shift happens, stresses transfer through the foundation and structural support members, pulling and pushing your home apart at the seams.
Protecting Your Home From Mine Subsidence Damage
Our team of professional foundation repair experts has proudly helped homes affected by mine subsidence for years. When you schedule your free inspection, we’ll schedule a visit to evaluate your property and foundation, assess any damage, and determine the root cause of the issues. Once we identify the factors putting your home at risk, we go to work tailoring a mitigation and foundation repair plan that puts your property back on a solid footing. Every case of mine subsidence damage is different, but they all have a real family behind them, trying desperately to save their home. We’re ready to help. Request a free home visit from A.M. Wall Anchor & Waterproofing today.