How do I know if a crack in my foundation is serious?

Crack width is the primary severity indicator. Hairline cracks under 1/16 inch are typically cosmetic results of normal concrete curing. Cracks between 1/16 and 1/4 inch warrant quarterly monitoring. Cracks wider than 1/4 inch, any horizontal crack in a basement wall, or cracks showing lateral displacement across the crack face indicate active structural movement and require professional evaluation. See the foundation cracks page for a full identification guide.

What is the shrink-swell cycle and how does it damage foundations?

The shrink-swell cycle occurs when clay soil absorbs water and expands, then dries and contracts. Expansion exerts lateral pressure against foundation walls, while contraction pulls bearing support away from footings. Each seasonal cycle advances cumulative movement. In the Kansas City and Des Moines metro areas, rainfall varies dramatically through the year, driving repeated expansion and contraction that progressively shifts foundations. The soil science page covers the mechanics in detail.

Does Des Moines have clay soil that damages foundations?

Des Moines sits on glacial till deposited during the Wisconsin glaciation, and much of the metro area has clay-rich soil with moderate to high shrink-swell potential. The Des Moines Lobe till contains significant clay content that expands and contracts with moisture changes. While not as extreme as Kansas City's Wymore-Ladoga complex, Des Moines clay soil generates enough seasonal movement to produce foundation settlement, wall cracking, and frame distortion in homes throughout the metro area.

Is foundation repair worth the cost?

Foundation repair protects both the structural integrity and the market value of the home. Unrepaired foundation problems are progressive — they worsen with every seasonal cycle. The cost of repair increases as movement advances because more piers, more wall stabilization, or more extensive excavation becomes necessary. Homes with unresolved foundation issues sell for significantly less than comparable homes with stable foundations or completed repairs with transferable warranties. For cost details, visit the cost and economics page.

Why is the frost depth deeper in Des Moines than Kansas City?

Des Moines has a deeper frost line (42 inches) than Kansas City (36 inches) because central Iowa experiences colder and more sustained winter temperatures. The frost depth is the maximum depth to which ground freezes in winter, and building codes require footings to extend below this line to prevent frost heave. Deeper frost lines mean deeper footings, more excavation for repairs, and greater exposure to seasonal soil movement along the full depth of the foundation wall.

Sticking Doors & Windows: Foundation Movement Indicators

Doors and windows that stick, jam, or refuse to latch are among the earliest interior signs of foundation movement. When a foundation settles unevenly, the structural frame above it shifts out of square. Door frames become parallelograms. Window frames warp from rectangles into rhombuses. The gaps change, the contact points change, and hardware that once aligned perfectly no longer meets. A sticking door is not a door problem — it is a frame racking indicator that reveals what is happening at the foundation level.

The critical diagnostic question is whether the sticking is caused by foundation movement or by seasonal humidity changes. Both produce similar symptoms, but the causes are fundamentally different and require different responses. Foundation-caused sticking is year-round, progressive, and worsens over time. Humidity-caused sticking is seasonal, reversible, and returns to normal when moisture levels drop. Identifying which mechanism is at work determines whether you need a foundation evaluation or a dehumidifier.

What Does Foundation-Related Door and Window Sticking Look Like?

Foundation-driven sticking produces consistent, directional binding that corresponds to the direction of structural frame distortion. A door that sticks at the top on the latch side, for instance, indicates the door frame has racked so the top latch corner has moved closer to the jamb. The binding point is not random — it maps directly to the geometry of the frame distortion, which in turn maps to the direction of foundation movement below.

Examine the gaps around a closed door for the clearest visual evidence of frame racking. In a properly squared frame, the gap between the door edge and the jamb is uniform — roughly 1/8 inch on all three sides. In a racked frame, the gap is wider on one diagonal and tighter on the opposite diagonal. A gap that measures 1/4 inch at the top hinge side and nearly zero at the top latch side reveals that the frame has shifted into a parallelogram shape.

Windows exhibit similar distortion patterns. A double-hung window in a racked frame will bind on one side and gap on the other. The sash may tilt visibly when raised. Casement windows may fail to seat flush against the frame when closed, leaving a visible gap along one edge. Sliding windows may derail or become extremely difficult to move as the track shifts out of parallel. In each case, the binding pattern reveals the direction and approximate magnitude of the frame distortion.

Latch alignment shift is another reliable indicator. If a door latch no longer aligns with the strike plate — requiring you to lift or push the door to engage the latch — the frame has moved. Check the strike plate for wear marks. Fresh scraping or a new contact point above or below the latch hole confirms progressive frame movement. Deadbolts that no longer align with their receivers provide especially clear evidence because the tight tolerances of a deadbolt mechanism amplify even small frame shifts.

Why Does Foundation Settlement Make Doors and Windows Stick?

Foundation settlement transmits upward through the structural frame as a chain of displacement — the footing sinks, the wall above tilts, the floor system slopes, and the wall frames above the floor rack out of square. A house is a connected structural system. Movement at the base propagates to every element above. The door and window frames, being precisely fitted rectangular openings in those wall frames, are among the first elements to show visible distortion because even small frame changes produce noticeable operational problems.

Differential settlement is the specific mechanism — one section of the foundation sinks while adjacent sections remain stable. Uniform settlement (the whole foundation dropping equally) would lower the home without racking the frames. Differential settlement creates angular distortion. A door frame sitting over the boundary between a settled section and a stable section experiences the most racking because one side of the frame drops while the other holds. The soil science page explains the soil conditions that drive differential settlement in Kansas City and Des Moines.

Header deflection above doors and windows can compound the problem. Headers are structural beams that span openings in load-bearing walls. When foundation settlement redistributes structural loads, headers may carry more weight than originally designed for. The resulting header deflection pushes the top of the frame downward, compressing the gap above the door or window and creating binding at the top of the opening. Header deflection combined with frame racking produces sticking at multiple points around the opening.

How Do You Tell If Sticking Is from Foundation Movement or Humidity?

Des Moines homeowners must distinguish between humidity-related swelling — common in Iowa's humid summers with 36 to 39 inches of annual rainfall — and foundation-driven frame racking. Foundation-caused sticking is year-round and progressive. It gets worse over months and years. It does not resolve when the weather changes. Humidity-caused sticking is seasonal and reversible. Doors that stick in July but work fine in January are responding to wood swelling from moisture absorption, not structural frame distortion.

Track the pattern across seasons to make the distinction. Foundation-driven sticking worsens during the dry season (when clay soil contracts and settlement advances) and does not return to normal during the wet season. Humidity-driven sticking worsens during the wet season (when wood absorbs moisture and swells) and resolves during the dry season. If a door has stuck consistently for 12 or more months and the problem is getting gradually worse, foundation movement is the likely cause.

Check multiple doors and windows throughout the home to distinguish localized from structural causes. Humidity affects all wood doors relatively equally. Foundation settlement affects doors and windows in a pattern that corresponds to the settlement geometry. If three doors on the east side of the home stick but doors on the west side work fine, the pattern points to foundation movement on the east side. Random, scattered sticking with no directional pattern is more consistent with humidity or individual door issues.

Door Plumb Measurement

A 4-foot level held against the hinge-side jamb provides a quick plumb measurement that quantifies frame distortion. In a square frame, the jamb is plumb — the level's bubble centers. In a racked frame, the jamb leans. Measure the gap between the level and the jamb at the point of maximum deviation. Any deviation greater than 1/4 inch over the height of the door opening indicates meaningful frame distortion that is almost certainly structural rather than humidity-related. Humidity swells the door, not the frame.

Window Binding Pattern Analysis

Windows provide additional diagnostic value because they contain glass, which does not absorb moisture like wood. If a window binds, it is a frame issue, not a material swelling issue. Double-hung windows are particularly useful diagnostic tools. If the lower sash binds on the left side when raised, the left side of the window frame has shifted inward. Check the window frame for square by measuring the diagonals — equal diagonal measurements mean the frame is square; unequal diagonals confirm frame racking.

Sticking doors and windows from foundation movement almost always appear alongside other settlement symptoms. The frame distortion that binds doors also cracks drywall, separates trim, and creates gaps between structural elements. Checking for these companion symptoms helps confirm whether you are dealing with foundation movement or isolated door and window issues.

Look for these related symptoms throughout the home:

Sloping floors — the same settlement that racks frames also tilts floor systems
Foundation cracks — stair-step, diagonal, or horizontal patterns in basement or crawl space walls
Drywall cracks radiating from the upper corners of doors and windows
Gaps between the wall and ceiling on the settling side of the home
Gaps between baseboards and the floor, especially on the high side of a sloped floor
Chimney separation from the main structure

A single sticking door with no other symptoms may be an isolated issue — a hinge problem, seasonal wood movement, or a settling interior wall. Multiple sticking doors, especially when combined with sloping floors and foundation cracks, form a pattern that points strongly to foundation settlement as the root cause. The more symptoms present, the more confident the diagnosis.

What Should You Do About Sticking Doors and Windows?

Document the problem systematically before contacting any professional. Record which doors and windows stick, where they bind (top, bottom, latch side, hinge side), how severely they bind, and how long you have noticed the problem. Photograph the gap patterns around affected doors. Use a level to check jambs for plumb. This documentation helps any professional you contact understand the scope and pattern of the issue before they arrive.

Rule out humidity as the cause by tracking the sticking pattern through at least two seasons. If you first notice sticking in summer, note whether it resolves by mid-winter. If the sticking persists through all seasons, or worsens during the fall and winter dry season rather than the summer wet season, foundation movement is the more likely cause. A indoor humidity monitor (hygrometer) costing under $15 can help correlate sticking episodes with actual humidity levels inside the home.

Do not plane, sand, or trim doors to compensate for frame distortion caused by foundation settlement. Trimming a door to fit a racked frame treats the symptom and destroys your diagnostic indicator. If the foundation continues to settle, you will need to trim again — and you have lost the ability to measure the original frame distortion as a baseline. Leave sticking doors intact as measurement tools until you have determined the cause and whether the movement is ongoing.

If the sticking pattern points to foundation movement — year-round, progressive, affecting multiple doors in a directional pattern — schedule an evaluation with a structural engineer. An engineer will measure floor elevations, check wall plumb readings, inspect the foundation, and correlate interior symptoms with structural movement. Their report provides an independent diagnosis that you can use to evaluate repair options. For cost information on evaluations and repairs, see the cost and economics page.

Inspect the basement or crawl space beneath the affected area for visible foundation damage. Look for wall cracks (especially stair-step or horizontal patterns), gaps between the sill plate and the foundation wall, water stains indicating drainage problems, and any visible displacement of support posts or beams. Foundation symptoms visible from below often confirm what the sticking doors are suggesting from above. Document these findings with photographs and measurements to share with any professional you consult.

Frequently Asked Questions About Sticking Doors and Windows

How do I know if a crack in my foundation is serious?: Crack width is the primary severity indicator. Hairline cracks under 1/16 inch are typically cosmetic results of normal concrete curing. Cracks between 1/16 and 1/4 inch warrant quarterly monitoring. Cracks wider than 1/4 inch, any horizontal crack in a basement wall, or cracks showing lateral displacement across the crack face indicate active structural movement and require professional evaluation. See the foundation cracks page for a full identification guide.
What is the shrink-swell cycle and how does it damage foundations?: The shrink-swell cycle occurs when clay soil absorbs water and expands, then dries and contracts. Expansion exerts lateral pressure against foundation walls, while contraction pulls bearing support away from footings. Each seasonal cycle advances cumulative movement. In the Kansas City and Des Moines metro areas, rainfall varies dramatically through the year, driving repeated expansion and contraction that progressively shifts foundations. The soil science page covers the mechanics in detail.
Does Des Moines have clay soil that damages foundations?: Des Moines sits on glacial till deposited during the Wisconsin glaciation, and much of the metro area has clay-rich soil with moderate to high shrink-swell potential. The Des Moines Lobe till contains significant clay content that expands and contracts with moisture changes. While not as extreme as Kansas City's Wymore-Ladoga complex, Des Moines clay soil generates enough seasonal movement to produce foundation settlement, wall cracking, and frame distortion in homes throughout the metro area.
Is foundation repair worth the cost?: Foundation repair protects both the structural integrity and the market value of the home. Unrepaired foundation problems are progressive — they worsen with every seasonal cycle. The cost of repair increases as movement advances because more piers, more wall stabilization, or more extensive excavation becomes necessary. Homes with unresolved foundation issues sell for significantly less than comparable homes with stable foundations or completed repairs with transferable warranties. For cost details, visit the cost and economics page.
Why is the frost depth deeper in Des Moines than Kansas City?: Des Moines has a deeper frost line (42 inches) than Kansas City (36 inches) because central Iowa experiences colder and more sustained winter temperatures. The frost depth is the maximum depth to which ground freezes in winter, and building codes require footings to extend below this line to prevent frost heave. Deeper frost lines mean deeper footings, more excavation for repairs, and greater exposure to seasonal soil movement along the full depth of the foundation wall.