How To Fix A Concrete Crack Before The First Frost

A woman went down on the front walk of that school on a Tuesday morning in October, in front of forty children waiting for the doors to open. The lip that caught her toe was a quarter of an inch. I had walked over it twice a day for two years. I was the head custodian at one public school for forty years. Eleven slabs of sidewalk between the parking lot and the front doors, and a district that bought de-icing salt by the pallet. I spread it, I shoveled it, and every April I looked at what it had done. Here is what is in this video. The free test that tells you whether what you have is a repair or a phone call, using four quarters and the number the accessibility rules use. In a lot of American towns that sidewalk is yours, not the city's, and one town puts the liability on the owner in writing. What salt really does, which isn't what everybody thinks. Rock salt has almost no chemical effect on cured cement. It lowers the freezing point, so your slab freezes and thaws more times every winter. But the federal highway people and two state highway departments say calcium chloride and magnesium chloride do attack the cement itself. Go and read the bag in your garage that says safe for concrete. Why the tube matters more than the technique, and the four characters printed on every one of them that decide whether your repair lives. And the one nobody tells you, which is the reason your last repair split. A sealant has to grip two walls of that joint and not three. If it also grips the bottom it cannot stretch, so it tears. That is what the foam rope is for, and it is not filler. There is also one that sounds backwards and is not: you have to open the crack up before you can seal it. Then the part that puts a clock on all of this. Nearly every tube says forty degrees, but one professional product specifies the temperature of the surface, not the air, and in October your slab runs colder than your porch thermometer all day. There is a dew point rule almost nobody knows. And joints are widest in the coldest weather, which means sealing on a cold day is the one thing you should not do. I told people the wrong thing for twelve years about the same joint at the bottom of those steps. #HomeMaintenance #ConcreteRepair #Repair