Indoor Air Quality/de humidifers


QUESTION: I am thinking of buying a de humidifier. I have been searching the web for answers. Some sites give answers and others don't. So I turn to you hoping you know.

I live in Fl. All the rooms but especially the living room and
are like an oven in the summer. I understand that the dehumidifiers often will use less energy than an HVAC unit.

I also read that they don't cool down a room. What good are they? If they don't cool down a room, why bother at all? I'm stumped as to why there is even a market for them at all?

ANSWER: Hello Joyce,

Unfortunately, dehumidifiers do not provide any real cooling effect. Their purpose is to remove moisture from the air, and in doing so they actually produce heat, making the space warmer.  They are commonly used to dry out cool wet basements.  

In Florida most buildings must use central or wall unit air conditioning, often aided with fans to increase the cooling effect.  You may also gain some cooling benefit from keeping out direct sunshine (by closing window shades or using awnings/overhangs) and by keeping the attic space under the roof well ventilated.  

But no, the dehumidifier is not a good solution for you.

Steve Major

---------- FOLLOW-UP ----------

QUESTION: Boy! When I think of how close I came to buying one.... I have paper bags and cardboard on the windows and its still an oven in here, The big HVAC unit is expensive. Last month my bill was almost $300!

what about air coolers? Do they help?


Evaporative coolers only work well in very dry climates such as portions of the southwest.  Air conditioning (and its high cost) is a way of life in hot, humid Florida.  In fact, Florida was not widely settled until the invention of modern air conditioning in the first part of the 20th century.  Before that, many Florida-style houses were tall, two-story with broad overhangs and excellent airflow to keep them cool.  These houses are a thing of the past, and the small, low ranch houses can only be cooled by paying for the electricity to run an air conditioner.   

A whole-house fan, which draws air out and brings outdoor air in (used mainly during the cooler night hours) can help some, but will do nothing to remove the humidity from the air like air conditioning does.  I can't offer much more in the way of advice to get your place cool on the cheap.  

Best of luck,

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Stephen Major (Principal--Lakeland Environmental)


I can answer questions on indoor mold, indoor air quality, asbestos, and indoor moisture problems. This includes mold testing and mold remediation. PLEASE indicate your state or region, so I can provide the best possible answer.


I have extensive experience in the investigation, testing, and remediation of indoor fungal (mold) infestations, including the design and oversight of remediation projects, hands-on cleaning and removal, and safe work practices. I developed a successful mold remediator training and certification program, and have trained many mold workers and remediation supervisors in proper techniques. I have a strong knowledge of the ways in which moisture and airlow patterns in buildings can affect fungal growth and air quality.

BS Cornell University. IAQA Certified Mold Remediator. 40-hour HAZWOPER certification. NYS Department of Health Certified Training Director.

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