Unseen Foundation Cracks Endanger Expensive Basement Renovations and Indoor Air Quality
Since the new homeowner believes he is protected, there is no reason for him to postpone renovation of the basement into an expensive, state-of-the-art home theater center. After all, didn’t his contractor obey local code by installing a waterproof sealant on the exterior walls of his home’s foundation? And isn’t there a warranty on that protective membrane? Yes, on both counts.
Yet what this homeowner and many others just like him don’t know is that cracks will inevitably develop on the interior surface of any concrete basement wall. Experienced basement pre-finishing waterproofing contractors know that about 90 percent of those cracks will be superficial and present no risk of allowing moisture to seep into the basement. Yet somewhere among the remaining fissures is a homeowner’s nightmare: a slow developing crack that leads to serious water damage or health problems – or both.
If he could, Troy Murrell, owner and operator of Murrell’s Waterproofing in Atlanta GA., says he would seal all the cracks that naturally develop in the basement walls of new homes. But, generally, the cost is prohibitive – except for those homeowners who intend to spend tens of thousands of dollars on a renovation. In that case, a contractor would be wise to advise filling each and every crack, even if they are not yet leaking. Why? After a basement is finished, it is often not possible to detect a crack which is now leaking. Murrell believes crack injection may be the best water-damage insurance a homeowner can buy.
“If you see larger cracks, you definitely need to seal them with epoxy and polyurethane foam injections and stay on top of them. Once they leak, they’ll only get worse. If you see any sign of moisture, address it immediately,” he says.
The larger, more insidious problem is the small crack that may develop over time – after the foundation sealant warranty has passed and an expensive renovation has completely covered the walls. Murrells knows that you cannot fix what you do not see.
“The sad thing is these leaks don’t leak much water. It doesn’t even get your carpet wet, but you’ve got moisture with no air flow and that creates a breeding ground for unseen mold spores. These airborne mold spores can cause chronic respiratory and other health problems. Suddenly, the people who live in the home aren’t feeling very well and need medical attention and they don’t know why. A minor leak can end up doing many thousands of dollars worth of damage because it went undetected. There’s nothing a homeowner can do if the wall is covered up. They can’t monitor it. So before they renovate, I tell them to go ahead and invest in crack injection of existing cracks for insurance.”
The other scenario would be the more obvious outcome: flooding that severely damages furniture, costly electronic components and priceless belongings. Contractors can help homeowners avoid both depressing outcomes by advising them about the adverse affects of doing too much too soon after moving into a new home. He can also discuss the usage of battery back-up pump systems for his sump system.
Also, sometimes it is not a leaky crack that causes the problem. The holes left in the foundation walls for the eventual installation of water and sewer lines may be the culprit. Since the pipes aren’t put in until long after the foundation sealer has been there, a plumber will be expected to do the honors. But often an ineffective material may be used to plug gaps around pipes. “The plumber is not going to guarantee that it is not going to leak because he doesn’t know any better,” says the Atlanta-based contractor.
Murrell repairs foundation cracks with low-pressure injection using epoxy and polyurethane foam materials. Epoxies and polyurethane foams are the best, he says, because they adhere to the concrete, preventing concrete from further erosion due to moisture. Also, the materials holds a strong seal, even while concrete expands and contracts.
“There’s no way of knowing. It’s just one of those things. Until it leaks, you’re in the dark. So I would encourage all contractors to be frank. Say to the new homeowner, if you’re spending a lot of money on your basement, spend some more to repair all the cracks as an insurance policy.”