Foundation Corner Cracks

October 1, 2016

Mitchell writes and asks, “Why are the corners of the foundation of my house cracked? Is something wrong with my foundation?”

That’s a great question! You’re buying an existing home and some of the corners are cracked, or you’ve bought a brand new home and notice in the first year that a corner or two are already cracked! What?! Is something wrong with my foundation?

These cracks in the corners of the foundation are as common as a humid day in Houston, and are commonly called “Corner Pops” or “Corner Wedge Cracks.” There is really no need to fear when you see a corner pop. Unless the crack is severe and the rebar is exposed, then it’s really just a cosmetic issue. If it bothers you too much to see the crack, they can be patched very easily.

Brick, mortar, and concrete have different thermal expansion properties with hot and cold temperatures. Brick expands due to thermal expansion and water absorption. A concrete slab foundation is partially underground, has less exposure, is less porous than the brick, and is less expansive than the brick. Concrete and bricks have different characteristics of compressive strength and tensile strength. Stress is developed between the brick mortar below the bottom bricks and the top of the concrete. As the brick expands, the concrete slab foundation is trying to resist this expansion. The forces caused by this difference in expansion can easily cause the corner to wedge crack or pop off.

In most cases, the problem is merely cosmetic causing no structural damage to the foundation. It does not affect the performance of the foundation. If the crack or chip is extensive and/or rebar or tension cabling is exposed, I would recommend you have a foundation specialist or qualified handyman evaluate and repair as may be necessary. Minor cosmetic repairs to corner pops can be performed by most anyone with a bucket of parging material and a trowel. This minor repair not only makes an aesthetic improvement to the home, it also helps prevent water penetration which also prevents the cosmetic crack from possibly growing into a damaging one. There is also a miracle concrete epoxy that you can get in a regular style caulking tube.

Corner pops should be monitored to make sure they don’t get any worse. If you’re ever concerned, you can always contact a professional structural engineer for an evaluation. A great website with a lot of helpful information about soils and slabs in the Houston area is www.houstonslabfoundaitons.com

It’s our pleasure to help you with any inspection / building related question. Whether you’re looking to buy a home in a newly developed area or a home in an older established neighborhood, or just stay in the home you’re in now, please send us your question on any home related topic. Stay informed my friends.

Lee Rushing

Lee Rushing (TREC #21601) is licensed with the Texas Real Estate Commission as a Professional Real Estate Inspector with ProVantage Inspections, PLLC.