How soon should I see moisture levels improve after grading?

Question

An inspector showed me several spots in my basement where I have excessive moisture levels in the drywall along the exterior walls in the basement, and along parts of the exposed concrete block exterior walls in a few places. This seemed to be related to grading and downspout issues.

I have just had a grading company install drainage and re-grade around these problem areas. They appear to have done a nice job, but I am eager to know if it is solving the problem. I am very allergic to mold so I want to act quickly and decisively.

I will continue using a moisture meter to take readings, but how soon can I expect to see an appreciable change? Is there a particular measurement strategy you would use? I have been marking a few spots on my wall with painters tape with the moisture level written on it.

Or: at what point or under what conditions can I be reasonably sure that it hasn’t worked?

Answer 1

The first thing you want to do is check the drywall that was determined to have excessive moisture. There could be mold building up between the walls and drywall. You should also try to air out the basement and not wait for the moisture to naturally dissipate. As far as how fast you can expect improvement, it will depend on the amount of rainfall over the next few weeks/months since that's what was causing the problems in the first place. If, after you've had a few good rainfalls, the readings start to increase to the levels you're at now, then the problems still exist. If the reading start to drop, then you've solved the problem. Continue to monitor the the levels and see what happens. Cleaning the basement with a mold inhibitor would be a good idea too.