I recently removed mold from several of the baseboards in my unfinished basement (using a bleach/water mix.) I plan to add a dehumidifier to help stop the mold from coming back. Does anyone know if there is a chemical spray/liquid I can apply to the baseboards to prevent the mold from returning? My fear is that when I finish the basement and put up drywall, the mold will return, and I won't be able to see it.

Thanks,
Joe in KC.

jkennedy99, read your post with interest. I am not a contractor, nor am I a specialist at anything, but I have just been through a mold problem. We live about 3 hrs north of Massena NY, in west Quebec. Our house is only 7 years old, a bungalow. Our foundation is poured concrete in sandy soil. I have never had water in the basement, except for 3 occasions when rain came in each of 3 below grade basement windows that were left open, or the window wells filled up with snow melt in the spring and water came in under the window frame. We dried and vacuumed up the water and thought all was well.
Not so. After 4 years of my wife complaining of a musty smell in the finished basement, and her feeling ill with various maladies for several years, we decided to cut open the walls under the windows. Yikes! Mold city, it was everywhere. To make a long story short, I have just removed 800 sg.ft. of wall board, plastic vapour barrier, and fibre glass bats. All of the laminate floor had to be tossed as well. Also the beds, clothes stored in the basement, tents, books etc all had to go.

Using proper gear, disposable coveralls, long rubber gloves, and a full respirator face shield fitted with mold resistant cartridges, my son and I did all of the work. Now wating on spray foam (Walltite) insulation and new wall board.

Used a fantastic chemical for mold, called Concrobium, at Concrobium Mold Control . Applied it with a fine spray from a garden sprayer. Within 1 hour, the musty, earthy smell in the basement was GONE. Applied a second coat to be sure, and it smells great in the basement for the first time in 4 years.

Mold only grows where it is damp. Bottom line here, you must correct the reason for the dampness/water in the basement before killing the mold. It will only come back. Bleach does not work by the way. Everything I have read on the net says bleach is not the cure.

With regrading the land, R&R the basement etc, this will cost me $10K - $15K. BIG bucks for not taking preventative steps earlier. If ever I get water in the basement again, I will cut away the sheet rock and dry the wall thoroughly, then reinstall the sheet rock.
Good Luck!

Starchy, wow you've just describe the nightmare that I'm trying to avoid. Luckily, my basement is still unfinished so I can solve the problem for less money. The main problem, I believe, is that the previous owner put up plastic sheets on the base boards (no idea why). I removed all the plastic and have cleaned the mold on the wood with bleach water. It did seem to kill it, but I agree it could come back. Also, my basement in Kansas is very humid most of the year, and I do not have a vent system down there (again unfinished at this point).

As far as steps to take before finishing the basement, it sounds like you are suggesting spraying the mold chemical Concrobium, and installing new insulation (my is very cheap) that is mold resistant? I have purchased a dehumidifier as well to pull some moisture out of the air.

Sorry your wife felt bad for so long, I've heard mold can cause illnesses the doctor's can not figure out.

Joe

Starchy, one other question, what was the cause of the moisture in you basement? Was rainwater getting in somehow?

Good morning Joe,
The water we had in the basement came from rain and snow melt coming in under the basement windows when the window wells filled up with water. The ground was still frozen so the runoff had nowhere to go but to fill up the window wells and then into the basement. You seem to have a moisture/high humidity problem, rather than a leakage problem. First step you have done already, get rid of the plastic over the studs. Without insulation between the plastic and the cement wall will allow condensation to happen and that means water in the basement. Can’t figure out why the previous owner installed that plastic, makes no sense to me.

A couple of points though:
1. Check that the studs are not moldy. If they are, they will need to be disinfected or replaced.
2. Use duct tape and 6 mil plastic in a square about 18” x 18”. Tape these plastic squares in several places on the floor and walls. Sealed as best you can. Check these patches in 24 hrs then 48 hrs for condensation. If you see it under the plastic, you have identified where your moisture is coming from. Treat that cause before you spend any $ on the rest of the job. If you do not stop the moisture entry source, the mold will come back for sure, and then you will do what I just did, and still have to correct the moisture source.
3. If you stop the moisture source, then fibreglass bats between the studs will do. Cover that with 6 mil plastic before the gyproc and you are good to go. Lots of debate about taking the insulation down 2 feet below grade or to the floor. For the minimal cost difference, I would go to the floor. We are having our basement insulated with spray urethane foam. More $ than fibreglass but offers many benefits. We decided to go with a BASF product called Wall Tite. Can see it at WALLTITE
4. Everything I have read on the net says that a 20% bleach solution does not do a very good job at killing mold, preventing re-growth, or getting rid of the smell. This Concrobium product seemed to work great. I followed their instructions and let the product dry before venting the room. Within an hour of application, the musty, earthy smell was gone! The whole basement smells like it did when the house was built. It has been 4 days since we sprayed and no smells at all. Concrobium is available at home centers. I went to Home Depot here in Canada and bought the 20 litre (5 gal) pail, for $180.00. Used all of that and went back for another 3 gals to apply a second coat to be sure. Not cheap stuff, but when added to the total cost of this job, small potatoes.

Having been through this awful process, if I were you, I would dispose of all of the moldy baseboards and start with new. Again small cost compared to reinstalling what you have, painting again, only to rip it all out down the road, to say nothing of the possibility of them infecting the room later. Not sure if you mean conventional baseboards applied to the bottom of the walls, just like any other room in the house? Or do you mean the 2x4 sole plate of the wall framing? If 2x4, then treat to kill any spores, if conventional baseboard, the chuck it out.

I don’t know if any insulation is mold resistant. Mold needs dark, damp, and warm to grow. It will grow on just about anything. Mine was on the black paper (tar paper) installed between the cement foundation and the studs. You may not have this arrangement though..

I have many many hours of net research on mold, what it can do to you, how it grows, how to clean it up, and how to prevent. I can send you some very good links to sites on mold.

Number 1 above all else, STOP THE WATER OR MOISTURE SOURCE! Mold will come back if you don’t. If your situation is simply humidity, then maintaining your basement between 30% - 50% RH is where you want to be. Until finished, you may want to keep a fan going in the basement to move air about for the dehumidifier.
Cheers and good luck,
Ralph 

When you rebuild your walls do not use insulation in the bottm 2 feet of the wall cavity. You need to allow just a bit of warmth to reach the foundation/floor connect so that it can never freeze and heave.

ballengerb1, you have raised a significant point. I am one week away from having spray foam applied to my newly exposed basement walls before I re-gyproc. Please explain in more detail what you pointed out above. I am at the crossroads on this and must decide before next Wed AM. The company BASF, selling the WallTite brand, recommend that I have the foam sprayed 2" thick from above grade to the floor. I live in a very cold winter climate and am looking to do the right thing for my heating costs, my house, the environment and the comfort level in our home. Being a senior citizen, I do not want to do any of this again.
Thanks, Ralph

Here is the logic behind not insulating the bottom 2' of the baseemnt. Frost line for most construction is normally 42-46" from grade. Most basements sit about 5-6 feet below grade so the fronting and wall connect should never have a frost issue UNLESS there is an extremely cold winter. Even if that happens only once every 20 years the freeze at the connect can buckle to wall/foor connection. Leave that 24" bare but still with a plastic vapor barrier. It will be a bit warmer never freezing and the air is less trapped so it won't support mold as easy as an insulated dead air space. I think Quebec gets a bit colder than Illinois so I'd skip the insulation.