To determine if a sticking window is caused by foundation settlement rather than seasonal humidity, we recommend performing a few diagnostic checks focused on the frame’s alignment and surrounding structural cues:

• Check for uneven gaps: Use a tape measure to compare the gap at the top of the window sash to the gap at the bottom. A tapering clearance that narrows at the top often indicates the wall is being pulled inward by foundation movement. A difference of 1/8 inch or more in frame plumbness is a significant warning sign.
• Identify binding locations: Slowly open and close the window to feel for resistance. If the window binds or rubs specifically at the top corner, it suggests the frame has been torqued out of square by differential settlement.
• Look for accompanying signs: Structural movement rarely occurs in isolation. Check the area around the window for diagonal drywall cracks radiating from the corners or stair-step cracks in the exterior brick mortar. The presence of multiple symptoms, such as gaps between walls and ceilings or persistent jamming that does not resolve during dry weather, strongly points to a foundation issue.

In Colorado, our expansive clay soils frequently cause these structural shifts. While minor sticking can be seasonal, persistent operational problems warrant a professional evaluation. We recommend consulting a licensed structural engineer for a definitive diagnosis and design recommendations.

All information is for general purposes and may be updated without notice; estimates are preliminary and not binding until confirmed by an on-site inspection.

• Sticking Doors and Windows: Signs of Foundation Settlement