Central Texas is well known for its soil movement underneath. The soil is expansive clay, which means it swells when moist and dries up when it is dry. This movement affects things above it, including your roof.

Homeowners often overlook their roof as being affected by soil movement, and soil movement is one of the most important things to consider when assessing the longevity of your roof. Understanding how soil movement affects your roof will help protect it by spotting problems early.

The Relationship Between Soil and Your Home’s Structures

Every house is built to rely on its foundation's sitting level. The soil under that foundation expands and lifts. It then contracts and drops. Such changes result in minute tilting or settling across the home's base. The roof sits on the walls, which need to be straight, and the supports, which have to be aligned. So, any shift below the roof is bound to cause a shift in the roof. Perhaps you do not notice this at first. A window might begin to drag, or a door might stick a little. The same shifts can transfer stress all the way to the rafters, trusses, and roof decking. Gradually, the framing that once had perfect lines starts to flex, and that flexing affects shingles, underlayment, and flashing.


Central Texas Clay Soils and How They Cause Structural Stress

Soils that are mostly clay are what make up the Central Texas region. Soils that are primarily clay are highly hydrophilic and will expand and balloon after heavy rainfall. Clay soils are typically extremely dry during the Texas summers after a prolonged drought. This consistent cycle will exude a tug-of-war mannerism with the structure of the house. The initial stress of the foundation cracking or rising unevenly will transfer to the walls. The walls will then experience a twisting of the forces. When the foundation shifts, the roof support beams will be tilted to such a great extent that it will create irritating gaps or pressure points. Structural designs of the houses will be underprepared for these volatile soils, especially houses built a long time ago.

Soil Movement Causing Issues with Roof Decking

Roofing composites, for instance, depend on a stable circulation of vaulted framing. As framing circulation moves laterally, the vault decking may not have lateral support, leading to warping and pull-away from the support beams. This lateral movement relative to the support beams manifests itself on the vault surface as soft spots, unevenness, or great surface variation. This topside surface warping creates gaps as the heads of the fasteners lose grip and the shingles populate gaps that are otherwise vertical. Large gaps exposed to the great, ranging, horizontal winds and lateral rain of thunderstorms exacerbate the problem with fast-track condensation and moisture.

Why Soil-Related Shifts Cause Roof Leaks Over Time

The default assumption when seeking a source of a roof leak is old shingles and faulty flashing; a worn roof is always assumed to be the cause of a leak. However, this is not always the case. Movement in the structure is often the root cause. Wall movement will allow flashing to lose its seal, while angling of rafters will allow shingles to become unaligned. Roof valleys, where two planes of a roof meet, are often points of concern and can become unsealed and adjusted. All of these minor issues can add up and, over months or even years, can create a substantial gap, and roof leaks will occur in the seals around chimney bases, skylights, and roof vents/plumbing pipes. Homeowners are often confused by these leaks, as shingles can appear to be in perfect condition from the ground. The cause of the leak is not the materials; it's the structure. To catch this kind of leak early, a professional inspection or at least regular attic checks after major weather events are needed.

Signs of Soil Movement Affecting Your Roof

You can notice some early signs without being a contractor. Some signs can be seen from the inside of the house. Stress on the foundation can be indicated by cracks on top of the door frames, some sudden sticking of the interior doors, or cracks in the walls that are diagonal. Outside, be on the lookout for stair-step cracks in the bricks, gaps around the window frames, or changes in the slope of the roofline. Indoors, check the attic to see if there are sagging rafters or if there is daylight coming through the roof boards. In cases of significant soil movement, the gutters may be detached, or the fascia boards may become warped. All of these signs indicate the roof is most likely under strain as a result of the home's structure being misaligned.


How Experts Tackle Roofer Issues Due to Soil Expansion

A roof removal and installation or repairs can fix issues with fastened decking or warped shingles as a surface covering. These repairs can be superficial if the problem is deeper and related to the soil. However, many homeowners in Central Texas must first get foundation leveling or pier installation to stabilize the house, as roof repairs are often not done properly and are almost guaranteed to fail. A roofer's approach may include framing reinforcement, flashing re-securing, and ventilation additions to mitigate the temperature-induced stress. A seasonal cycle of monitoring is sometimes recommended to see if the repairs hold. The essential premise is that stability must be restored to the base of the home, as repairs to the roof alone will not be successful.

What Homeowners Can Do To Reduce Risk

Homeowners can mitigate the effects of soil movement in numerous ways, and one of the most important is to draw attention to the importance of sustaining consistent soil moisture around the foundation. To mitigate rapid shrinkage during dry spells, use a soaker hose on a timer. To enhance proper grading so that water does not pool in one location and cause excessive soil expansion, clean gutters regularly to prevent water from flooding the foundation, and allow the soil to dry.

Annual roof inspections help you address minor problems before they develop into something major. Working in conjunction, a roofer and foundation specialist provide homeowners with the finest defense against soil movement in the Central Texas area.