We have a whole house dehumidifier at our Florida house. It really only turns on if we are away and the AC is set at a higher temperature than normal. When we are here in Florida, we keep the AC set to 74 during the day and 70 at night. The AC takes care of the humidity as long as we keep the house cooler than about 80. It clicks on somewhere around there, depending on the outside temperature and humidity. It never turns on when we are at home.

At our NoVA house, we have a dehumidifier in the basement. The AC easily takes care of the humidity in Virginia. We don't even really need the basement unit.

We live in a very humid coastal area, and we had whole house dehumidifiers installed on both floors (separate a/c units). $700 each sounds about right. Installation was easier on the one in the basement, as there was an existing return that could be used. The one in the attic required the installation of a new return. They work great and keep the humidity below 60% all summer long.

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:We have one: it's our air conditioner. When working properly, AC should take care of any area with proper ventilation. Un-vented basements may need additional help.

What is your typical relative humidity from June-August? Our rooms run between 48%-54% all summer and that feels humid to me.

That sounds fine. It's around a 55 degree dew point. Any dew point below 60 is nice to folks who grew up in the mid-atlantic.

This is in relation to the outdoors. A humidity level of 60 in thr home creates a potentially toxic mold environment. This is the main reason some basements smell like absolute shit.

Anonymous wrote:

Anonymous wrote:We have one: it's our air conditioner. When working properly, AC should take care of any area with proper ventilation. Un-vented basements may need additional help.

What is your typical relative humidity from June-August? Our rooms run between 48%-54% all summer and that feels humid to me.

That sounds fine. It's around a 55 degree dew point. Any dew point below 60 is nice to folks who grew up in the mid-atlantic.

Anonymous wrote:We have one: it's our air conditioner. When working properly, AC should take care of any area with proper ventilation. Un-vented basements may need additional help.

What is your typical relative humidity from June-August? Our rooms run between 48%-54% all summer and that feels humid to me.

Anonymous wrote:

Anonymous wrote:Live in a 1964 house and our original Aprilaire broke about a year ago and leaked under the flooring. HVAC guys disconnected the whole thing, having it replaced would have been a lot of money, and the unit probably wasn’t doing much anyway and we never noticed. So he disconnected and said just get a little room humidifier if you notice dry eyes or whatever. And we have never noticed.

Dry eyes would be a problem for a humidifier, not a dehumidifier.

Dang. Totally read the OP wrong. Ignore me.

Anonymous wrote:

Anonymous wrote:

Anonymous wrote:There are only a few days a year when it’s uncomfortably humid but too cool for our a/c to take care of it.

This. So long as the AC is appropriately sized for the space, it's the easiest way.

It really depends on how well-insulated and airtight your house is. If there's not enough cooling load for the AC to run there won't be enough dehumidification. What a lot of people don't understand is there's no such thing as "standard" construction, houses can vary a lot -- like a factor of ten -- in how tightly they're built.

Agree that sizing is also important. An oversized AC will have short run times which will tend to remove less humidity.

What temperatures to they target sizing AC for? If we run it at 70 or so it keeps humidity down below 50 on a day like today, but at 75 degrees - humidity hits 60+

Anonymous wrote:

Anonymous wrote:There are only a few days a year when it’s uncomfortably humid but too cool for our a/c to take care of it.

This. So long as the AC is appropriately sized for the space, it's the easiest way.

It really depends on how well-insulated and airtight your house is. If there's not enough cooling load for the AC to run there won't be enough dehumidification. What a lot of people don't understand is there's no such thing as "standard" construction, houses can vary a lot -- like a factor of ten -- in how tightly they're built.

Agree that sizing is also important. An oversized AC will have short run times which will tend to remove less humidity.