Attic Mold

[Me]

My attic has a humidity problem that caused a lot of mold to grow on the north side of the roof deck (underside.) I had the mold chemically treated but need to get the humidity source taken care of.

Previous owners of the house had two full baths with showers vented to the attic. The vent pipe terminates into the bottom of a passive roof vent but I don't think its actually getting out of the attic. Is there a proper method for venting this humid air?

I'm told this roof is known as a "hip" roof?? I don't have any soffet venting - Just four vents near the top of the roof.

Thanks for any advice.

Tom

[steve]

It needs to go out of the home....period. You can do it with a soffit vent, a roof vent, or a side vent. Each shower fan requires its own vent termination, and since you dont have soffits, you can go right up to the rooftop, and use a proper vent stack with it. If the run total equals more than 14 feet on either fan, that fan will need to be ran in hard pipe.

[Dave Solly]

"Steve@carolinabreezehvac" wrote in news:BDSod.313$ [e-mail]:

Can you use a plumbing vent, or does the vent have to be just for the bathroom exahust fan? I have a similar problem except I don't have any mold. The house was built with a cedar roof so the attic had plenty of ventalation. Now it has a composition roof and there's no place for the bathroom humity to go. Therefore, we never use the exhast fans.

Dave

[steveki]

It must vent in a separate pipe; it must not use an existing plumbing vent pipe. The plumbing vent pipe is specifically sized for the existing number and type of plumbing fixtures.

[steve]

Has to be dedicated fan vents..cant share them with a plumbing vent.

[newsgroups01REMOVEME]

Good advice, once I had a plugged up sink. So the harware guy sold me this divice, it inflated in the pipe and pulsated water at the clog. Well I inserted it, and turned on the water, the water flowed(in this case 'pulsated') and flowed and flowed. We couldn't figure why the water kept going. Well then we got our clue. I sounded like it was raining due to our noise rain gutters. That's when the light bulb went on, we ran outside to find that water was 'pulsating' out the top of the plumbing vent.

Now in hindsight of that incident, and the question about tying the bathroom vent into the plumbing vent, good idea NOT to. We would have pumped water into that drain till the water came running down the stairs. We were newbies. ;)

later,

tom @ CarFleaMarket.com

[Me]

OK Thanks. So I'm clear, are you saying it can blow into a roof vent? My concern is that not all of it blows out but eddies back into the attic. I was wondering wether there is a type of roof vent designed for exhaust like this to make a tight fit and keep rain out. Also, you say each vent requires it's own vent termination - The exhausts are run with hard pipe but come together in the middle of the attic to form a single exhaust. This is incorrect? Should I change it?

Tom

"Steve@carolinabreezehvac" wrote in message news:BDSod.313$ [e-mail]...

[steve]

You need to run each out of the attic, to the outside of the home, on its OWN line. Two roof caps and you are done.