Concrete Pieces Chipping Out in Cold Weather

Tommy in AR


I have a concrete patio that, whenever it gets covered in snow or ice, gets spots about the size of a quarter that crack and pop out. I'm including a picture here. What’s causing this and can it be repaired?

Great question, Tommy. It’s not so much the concrete as it is what’s inside it! It sounds like the company who mixed the cement for the patio used an aggregate that was fairly porous. They may have used ironstone, coal, shale or limestone. These materials will hold moisture and, when they freeze, especially near the surface, they expand and “pop out” as you have observed. The good news is that this is a cosmetic defect and doesn’t really affect the structural integrity of the slab. Small patches can be made by cleaning out the loose particulates in the hole and use a concrete patch material. But, if you’ve got an over abundance of these pop outs, you need to consider re-surfacing. I would take a look at some of the products from Quikrete. They’ve been tackling these issues for a while and have some good solutions for both re-surfacing and patching.