HOW MUCH DOES IT COST TO FIX A BASEMENT LEAK? The cost to fix a leaky basement comes down to the severity of the situation. It also depends on the condition and size of the home in question. "Leaky Basement Repair Cost" » It’s important to have a ballpark idea of cost, since we are in the teeth of winter now. Soon the ground is going to thaw. The average annual precipitation has increased in Canada, with continued change in the earth’s climate. Heavier and more frequent rainfall is a big factor as spring approaches. Web-link: