Attic condensation problem

bd38 · Sat Mar 12, 2011 12:29 am

Hi, my question pertains to a problem I have with condensation and leaks in my mobile home which at some point had a new roof installed (tin roof) after the original roof was removed. The problem area right now is in the vicinity of the bathroom and clothes dryer.

There is frost buildup along the eaves that I can see, as I cut a hole in the ceiling. There is not enough room to enter the attic due to the limited pitch. There is insulation and a vapor barrier, however there is really not any overhang on the eave and no soffits as a result. There is insulation squeezed right into the corner of the eaves where the frost is built up. Once the winter temps warm up, it melts creating the water problem.

We installed an electric fan in one end and gable vents, but obviously airflow is unlikely where the insulation is tight into the corner.

Have you seen this problem before? What can be done to remedy it?

Thanks
Kevin

Greg · Sat Mar 12, 2011 1:14 pm

Hi & welcome. As you have found ventilation in a mobile is difficult at best. The only other thing that you may be able to try in the unlikely chance that you have soffits would be add soffit vents. As you have found it is about impossible to get any air flow to that area.

Some here have added roof vents, but personally I don't like to cut into a roof if I don't have to.

Greg

RICKD · Wed Mar 16, 2011 4:23 pm

I agree with Greg. I avoid cutting into a roof at all cost BUT Metal Roof Overs are prone to create condensation especially in MF homes and its due to space restrictions...a lot of the newer energy efficient homes are being built with Flat ceilings to allow for more attic insulation but the typical home out there has cathedral ceilings which is much more difficult to properly insulate and properly ventilate so they are more prone to condensation and ice damming problems. also *Most existing homes have a low pitch roof so the factory was limited to the amount of insulation they put between the rafters and roof decking. Getting enough ventilation is going to be your solution. I installed a metal roof on my previous home and the first summer i got condenstation ended up swapping my existing vent to a powered vent and it solved my problem .If you have roof vents now you could always swap them out for powered ones like these below

http://www.lowes.com/pd_85947-228-RV26M ... of%2Bvents

oldfart · Mon Mar 21, 2011 7:20 am

Kevin, I've seen this before! Some time when ya get a chance type "condensation" in the search area and my name should come up. LOTS!

Anyways, I went to Lowes and bought the biggest attic fan I could fit into the south gable of my attic. Then bought the same size louvered vent and whittled a big opening in the north gable. I put the fan on a timer so it comes on every morning 1/2 hour before daybreak and runs till noon. Mind ye, it only needs to run on frosty mornings. That's the only time I had a problem. I don't know what to say about the insulation jammed down in the corners but get enough air moving up there and it'll help. That fan of mine will suck little birds into the louvered vent! Audie...the Oldfart.