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TOPIC: Ventilation

How do I vent a temperary flat roof

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Hi there, I noticed in other messages some people didn't give enough info. I hope I don't give too much, but I know little about construction. So here is everything I know. 1. I had a 60 x 30 Concrete block basement put in which I am living in until getting the money to add the upper levels of the house. 2. To do this a 2x6 treated top plate and 12" TGI wood beems or whatever they are were put on for the support for the upper level. 3. On top of the TGI beams, Advantech plywood was put down. Then a Rim board was put all the way around making a perfect box. 4. To make the roof water proof and ensure I could build up while living in the basement without leaks (we have 48-54 inch annual rainfall here) I had a continuous rubber membrane roof put on as the roof. They glued it down and made it ultra smooth across the entire subfloor. Problem 1: With the Membrane on and the rafters / beams / open, condensation was forming droplets on the advantech ceiling on the inside and it would litterally rain inside after a bit of build up. We needed to heat the basement so I bought an 80K BTU wood stove. I was told that once the ceiling was dried out I could put up insulation and drywall. So I got the stove, and dried things out. But by this time mold was growing on the ceiling. I was told bleach and water will kill it if I spray it, let it dry, and then put up the insulation. So I sprayed a room or two. I don't know if it killed the mold since it still looks the same, but I got it dried out again. So with the stove cooking everything and making it dry I thought It should be safe, but I am skeptical, to insullate. So I just laid the insulation (6.25" R-19) into the ceiling which leaves about 6 inches of air in the top of the chambers. I went back and pulled the insulation down after a week and poof. The entire ceiling above the insullation is wet! argh!!! So I have talked with lots of contractors and people that do roofs which are not many in this rural area, and nobody has heard of anyone doing what I am doing and can't give me any advice. The only advice I have got is from my dad that says to treat the TGI chambers like they do in a vaulted ceiling and put sofit vent on each end of the chamber so air can get in and out. Making a mini-attic. He says this will get rid of the moisture, which will get rid of the mold. So that means drilling 96 2 inch holes in the rim board and putting in sofit vents. Is that right? Will that solve my issue with the moisture and mold. Then when I build the next level of the house, do I plug the vents, or leave them? Sorry for so much information, but I figure I better tell you everything than not tell you enough. Your help is greatly appreciated. p.s. if you want pictures of how this basement is build go here http://spaces.msn.com/members/neurongames/ At the top, click on the photos tab, when that page comes up, select "Area 52 - Dragonfly Hollow" from the "view:" drop down. There are tons of pics of the inside and outside of the basement being built. Sincerely Randy
Randy Trulson
It's all in your head!

1/23/2006
You do have a problem. First is to kill the mold you may need more than bleach. I would consult an expert. You need an air barrier to keep the warm moist air from condensating against the cold deck. Also you need an air exchanger to exhaust the moist air and bring in fresh air. I would suggest buying styrofoam insulation and laying it over the roofing mebrane, covering it with house wrap to keep the sun off. Tape the joints and lay some concrete blocks to hold down the insulation. This way the membrane will act as the air barrier and the insulation will keep the deck warm. Clean the mold and you may want to spray with formaldahyde.
Allan Reid
Dura-Loc Roofing Systems, Inc.

1/23/2006