over the last few months, i've been reading with interest about energy efficiency, and have been really impressed with this forum. i am trying to solve an issue with humidity, particularly on the second level of our home.

we live in florida in a 2 story 1920's lath and plaster home. the home has a steeply pitched roof, which was recently replaced. at the time of the replacement, we had a large oak tree "nestled" in the corner of our l-shaped home which covered the majority of our roof. we were cautioned by our roofers to vent the attic, but a ridge vent was not a possibilty. therefore, a vent was placed above one of the upstairs bedrooms. the attic also has some air circulation holes on the side of our home, just under the peak of the roof. our soffits are not vented. to give further detail, the "short end" of the l shape of our home was an addition. a flat roof was placed atop this addition, which certainly would not have been my decision had we lived here at the time!

unfortunately, the oak tree's roots began lifting our foundation quite severely within the last several years, and we finally were granted permission to cut it down. prior to cutting the tree down, we had more humidity upstairs than downstairs, but the humidity really intensified once the tree and all of its shade was cut down. we have a bathroom upstairs covered by the flat roof which only complicates the issue.

we had our local energy company come in to do a check-up, and aside from saying we could add a little more insulation to the attic, they were not of any help in suggesting how to solve the humidity issue. i repeatedly brought this up with our old air conditioning company, but as they installed the system, they seemed reticent to institute any changes. the vents from the upstairs air handler go to the bathroom and bedroom in question last.

we have a two zone rheem system, with one air handler in the attic itself (a nightmare in terms of keeping the drains clean, has overflowed on three occasions) and one in an area under our stairs on the first floor (drains only clogged once). the descriptions on the rheem heat pumps are: (downstairs) classic high efficiency - compressor rla 12/2/12.2. lra 67, outdoor fan motor fla 1.3, hp 1/5; (upstairs) classic xii imperial super high efficiency heat pump - compressor rls 11/5/11.5, lra 62.5, outdoor fan motor fla 8, hp 1/10. i have no idea on the seer ratings on these units. the upstairs unit is about 10 years old and is just coming out of warranty.

we have switched air conditioning companies (the new one represents several lines, not just rheem) and i'm trying to do some upfront research on what might happen should our upstairs unit fail. if any of you have suggestions on how we might solve our humidity issues, and recommendations about new systems, i'd really really appreciate it. no one seems willing to touch this, even with a 10 foot pole. as an aside, i've seen ads about a gas-powered dehumidifier, which seems to be a separate outdoor unit, which we certainly might consider installing as well (?).

thank you thank you thank you in advance.