frost line

noun

1. the deepest point in the ground to which frost will penetrate
2. the limit towards the equator beyond which frosts do not occur

frost line

1. In regions where there is no permafrost, the maximum depth to which frost penetrates the ground in the winter.
2. The lower limit of permafrost.
3. In tropical regions, the elevation below which frost never occurs.

Example Sentences

“Our water lines are not buried beneath the frost line. They’re not insulated. And they’re old,” she said.

From Seattle Times

“Our water lines are not buried beneath the frost line. They’re not insulated. And, they’re old,” she said.

From Seattle Times

Pipes are initially buried under the ground, below the frost line, before the final section of the pipe then rises vertically.

From BBC

Your local building department can advise you on the frost line in your area.

From Seattle Times

Some, such as Limes Germanicus, the former site of a Roman wall on the Empire’s frontier in Germany, are now just trees and grass, recalling the Robert Frost line, “Whose woods these are I think I know.”

From Washington Post