How To Create A Moisture-Free Basement?

roboman

Greetings all. New guy to the forum here. I will try and keep this short and sweet for the sake of brevity

Long story short, I currently have a finished basement. The previous owners were, to be honest, idiots. The home is built on ledge and as a result the landscape is graded poorly. Because of this, the home used to have a serious problem with water flowing inside the foundation. By serious problem I mean that it was like a river running through certain spots.

For reasons unknown to me, the previous owners thought it would be a brilliant idea to finish the basement, even with the water problems. I have since taken care of the water problems by installing an interior drain system.

My biggest task now though is to gut the finished area and rebuild it once again. My #1 goal is to make sure the basement is not moist in the least. I want a nice comfortable area that I can enjoy without having to worry about mold or funky odors taking over the place.

My question is, what steps do I need to take to make sure that this happens? My plan is to rip down the current crappy 1970 insulation and have spray foam installation professionally installed. After that I plan to buy a "top of the line" Santa Fe dehumidifier (one of those big bastards) and have it set up to take care of the whole downstairs and any moisture.

Am I on the right path? What else do I need to do?

Thanks!

firehawkmph

Robo,
sounds like you're treating all the symptoms, but did you ever correct the grading outside to divert the water away from the house? That would be my first step before I do anymore on the inside. If you still have damp walls, spray foam isn't going to correct that. Most of the interior drain systems I have seen divert the water once it gets on the inside, but you are better off if it never gets to that point. Block is porous and if water sits against it long enough, it will either find its way in or wick its way into the block and cause a dampness in the basement.
Mike Hawkins

roboman

Hi there Mike.

With the ledge everywhere, regrading doesn't look to be possible. I should have described things better in that the poor grading is on the unfinished side of the house. The finished area is surrounded by proper grading.

Just Bill

The only sure cure is to raise the basement above grade level, that obviously is not an option. Proper grading and having gutters/downspouts that get the water at least 6' away from the foundation will solve 90% of basement water problems. The other 10% are not easily cured. I had a dry basement for 35 yrs, suddenly was getting a LOT of water coming over the slab edges. Seems I now have a river under the house, seemingly created by blasting about a mile away for a highway. I added a sump and pump, which only runs during droughts........figure that one out. We got 6+" of rain from Irene, it only ran once.

vanbuchanan

I am using a brand new Ryobi Moisture Meter and the included instructions leave much to be desired. While it shows how to use the meter, it does not explain how to interpret the results.

I recently moved into a new home with new home furniture and would like to finish the basement, but first I want to make sure it is moisture free, or at least safe enough to finish.

I guess my first question is: Are moisture meters meant to be used on a concrete floor in a basement, or only on the walls?

If yes, then is a reading of 60 - 70 % enough to raise concern? The cinder block walls were anywhere from 0-20% depending how close it was to the French drain.

Any help is appreciated.

Maintenance 6

vanbuchanan, you really should start a new thread, rather than tack on to this one. Contact moisture meters can measure lots of surfaces. Some will decieve the meter though. Certain wall coverings and ceramic tiles will drive moisture meters crazy. Mold needs 60% or greater to thrive, so yes, 60-70% is a concern. 0-20% is very dry for masonry that is below grade. Does it stay at 20% even after a significant rainfall? Concrete floor slabs are tough. They can be metered, but vary a lot depending on how they were installed. Whether they were poured directly on grade or had a stone base put down for drainage. Whether they had a vapor barrier underneath and how good the install was. They can vary a lot from place to place in the same slab. The relative humidity in the air needs to be a concern too.