Repair or replace: how to decide on an old foundation

A foundation replacement is a big job and a big bill. If a wall can be repaired and kept sound for many more years, that is the right answer. Brian Lee Smith does both kinds of work, so there is no reason for him to push you one way.

But the reverse is true too. Repairing a wall that is past saving means paying for patches that will not hold. The trick is being honest about which one you have.

Almost every repair or replace call comes down to the same four things.

• How much of the wall has failed: one corner, or the whole length?
• Is it still moving: bowing more each year, cracks growing?
• How much water comes through, and can the source be fixed?
• What is the house doing: floors settling, walls cracking upstairs?

If the wall is straight and the trouble is local, repair it. That covers a lot of old Hoopeston foundations: mortar that has washed out in places, a few loose stones near a downspout, a crack in block that opened once and stopped. Repointing the joints, resetting stones and fixing the water source outside can put that wall back in good order.

Repair also makes sense when the wall has an old, stable bow that has not changed in years and the house above is sitting fine on it. Stable is the key word.

If the wall is bowing and getting worse, if the stones are loose all along it, if mortar has turned to sand through the whole wall, or if the house has started settling into the foundation, the wall is done. Patching sections of it buys a year or two at best, because the parts you did not touch keep failing.

That is where Brian's main work comes in: taking out the old foundation and replacing it with modern materials, so the house sits on a footing below the frost line and a solid wall.

It is common for a house to need both. One wall, usually the one that takes the roof water or sits in the low side of the yard, is too far gone and gets replaced. The other walls are sound enough to repoint and keep. That can cost a lot less than replacing everything, and it is a fair way to handle an old house.

A few things push the decision one way or the other. If you are planning to finish the basement, a dry, solid wall matters more than it does in a basement you only walk through. If you are adding on or putting weight on the house, like a new second story or a heavy masonry chimney, the foundation needs to handle it. And if you plan to sell soon, a buyer's inspector will look hard at a bowed wall, so the decision may get made for you.

Cost factors matter too, in plain words: how long the wall is, how deep, how easy it is to dig along the outside, what is in the way inside, and how much of the house is sitting on the bad section.

Send Brian photos of each foundation wall, the worst spots up close, and the outside of the house showing the ground and downspouts. Tell him what you have noticed upstairs. Text them with your town to (217) 549-2230 and he will tell you which way he sees it going, and why.