Looking for suggestions from the great knowledge on this board as to the best way to treat a small mold/mildew problem. Building a small vacation place up north where I installed my foundation & framed the first floor deck prior to the winter. Covered everything with a heavy poly tarp (1 piece) to keep everything dry till spring. Didn’t pour the floor as I was a little leary about possible frost. Left open the small foundation windows to get some ventilation, but at last check , it appears that the warmth of the ground inside the foundation caused some consensation on the TJI’s & underside of the Advantec sheathing, resulting in some mildew. I provided some more ventilation by removing some plywood I had over some other windows in the walkout part, just to get more air flow and keep a steady inside/outside air temp. Any suggestions as to the best way to treat the mildew? My thought was to let things dry out a bit & spray with a mixture of bleach & water & wipe down. Thought maybe once that dries, there may be something else put on it to prevent any mold issues. Any ideas?
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I just went through the same scenario two weeks ago. I started framing oct. 1st roof on dec. 15th and the underside of advantech subfloor was spotted all over with mold mostly around the perimeter. We had 14" inches of rain and some snow but I was the only contractor in the area that had this problem. I called the rep from advantech and he had no advice. I researched and found mixing 1 to 4 ratio bleach and water spray on heavy let soak 15 min rinse with pressure washer made it look good as new. After drying with 2 heaters for a few days I sprayed a product I ordered on the net called impact to prevent any future mold growth. The whole process cost me over a grand and it killed me to soak the deck after getting the roof on and after all that rain. One bit of advice is to wear a good vapor respirator because the bleach fumes are strong. I had very good results with this and I feel bad for anyone who has to go through with this. The whole situation has me puzzled. I hope this helps.
Hey thanks guys. It has me a bit puzzled as well because I know nothing was getting thru the tarp. Only thing I can think is the moisture was coming up thru the stone inside the foundation & lack of enough ventilation kept the air warmer than the exterior causing the condensation. Did you wash down & treat all the tji's & underside of the advantec? It's not super bad, but I just want to be sure there are no issues later on. Appreciate your help, the advice about the respirator is appreciated. Hate the sound of putting a pressure washer to the advantec, sounds like I have some work to do.
Edited 1/29/2006 9:13 am ET by VT.lab
I use a product called Jomax for killing/ removing mold. It is a concentrate that you mix with bleach. Put the Jomax, bleach and water per instructions in a pump up sprayer and apply. Rinse with water and allow to dry. If you are painting the surface you can always add a mildewcide to the paint. Costs about $3 per gallon at the paint store and they will shake it into the paint. If your not painting the surface make sure it is dry before closing in or covering up.
I'd treat a small mold problem during construction by ignoring it. Happens all the time and it's not a big deal. Once you get the place dried in, the mold will go dormant. Mold is always there, and the best way to control it is to control moisture. Spraying with bleach has downsides, including accelerated corrosion of the fasteners. If you really want to do something, check out Boracare's website. Borates also kill mold, and they're about as toxic as table salt.
Andy
"Never try to teach a pig to sing. It wastes your time and annoys the pig." Robert A. Heinlein
"Get off your dead #### and on your dying feet." Mom
Thanks Andy, will check that stuff out. Where can you get that stuff?
Edited 1/29/2006 1:44 pm ET by VT.lab
On line. I'd google it. I also suspect that regular old 20 mule Borateem might do the trick.Andy
"Never try to teach a pig to sing. It wastes your time and annoys the pig." Robert A. Heinlein
"Get off your dead #### and on your dying feet." Mom