Why Do Your Doors and Windows Stick? The Slab Foundation Connection in San Antonio

Doors and windows that suddenly stick are one of the earliest signs of slab foundation movement in a San Antonio home. When the concrete slab beneath your house shifts, the frames anchored to it move out of square, and openings that worked fine for years start to drag or refuse to latch. Humidity plays a part too, so the pattern of the sticking is what tells you whether the cause is seasonal or structural.

Humidity or Foundation? How to Tell

A door that sticks only during the most humid weeks of summer and then works again in winter is usually reacting to moisture in the wood. Foundation movement behaves differently. It shows up as a door that drags on one corner year round, a gap that widens at the top or bottom of a frame, or a deadbolt that no longer lines up with its strike plate. When several doors and windows on the same side of the house stick at the same time, that points to the slab rather than the weather.

What Slab Movement Does to Your Frames

A slab foundation sits directly on the ground with no crawl space underneath. When San Antonio's expansive clay soil swells with moisture and then shrinks during drought, the slab lifts and settles unevenly. Because your walls and frames are fixed to that slab, they tilt with it. A frame that was once a clean rectangle becomes a slight parallelogram, and the door or window inside it binds against the new angle. These shifts are often only an inch or two, but that is enough to throw the opening out of alignment. This is why planing a door or shimming a window rarely holds. The opening keeps moving as long as the slab does.

The Signs That Usually Travel Together

Sticking openings rarely appear alone. If the slab is moving, you tend to see diagonal cracks from the upper corners of door frames, gaps opening between the wall and the ceiling, floors that feel uneven underfoot, and cracks in exterior brick. Any one of these can be minor. Two or three together on the same part of the house is a reason to have the foundation measured, and in San Antonio's swell and shrink climate, catching it early usually means fewer piers and a smaller repair.

At Risen Foundation Solutions, we measure before we recommend anything. Our foundation expert uses an electronic measuring device called an altimeter to record elevation across your entire slab, referenced to a fixed point in your home. That data shows exactly where the slab has dropped and by how much, so any slab foundation repair targets the real cause. If a repair is not necessary, we tell you that, because an honest assessment is the point of the visit. Our proprietary steel pier system, fabricated in house, lifts the slab back toward level, and the frames around your stuck doors and windows come back into square as a result.

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