First the details - This is a second home and we're here around 1-3 weekends a month. The house is a raised ranch style log house in the Southern Berkshires (MA) - a cold, rainy, damp place. The basement / lower level is partly under the ground level and partly above. It gets pretty damp in the spring, summer and fall. Last weekend it was 82% RH in the basement as the dehumidifier had failed. I replaced the dehumidifier and it's all well in the basement floor / lower level now and close to the 50% RH I've set on the dehumidifier which drains continuously into a drainage pipe. The upper level unfortunately still has 70% RH. There is no air-conditioning and no house exhaust fan. In the winter, the heat (electric) keeps the humidity fairly low and there is no issue.

How do I reduce the RH levels in the upper level of the house? When we're at the house, if it gets hot, we open the skylights and turn on the fan - this cools the living space but the RH level is still around 70%. Outside RH is in the 50%-60% range in spring, summer.

  • Can't run a dehumidifier upstairs? I'd go so far as to sit it on a bathroom counter, draining into a sink, while you're away. Be sure it can't roll off.
    – isherwood
    Commented Jun 21, 2017 at 18:33
  • If you're keeping the windows open while you're there you can't expect to do much. Humidifiers shouldn't be run with open windows. They'll run too much and wear out or ice up.
    – isherwood
    Commented Jun 21, 2017 at 18:34
  • Yes, I could run a dehumidifier upstairs when we're not here - put it on the kitchen counter and drain into the sink. I couldn't run it while we're here as the noise would drive everyone crazy. In the summer we do tend to keep the windows open which makes the dehumidifier overworked.
    – Vasuvius
    Commented Jun 21, 2017 at 19:42
  • Most modern units have multiple fan speeds and are very quiet. Still, there's no point if you have open windows.
    – isherwood
    Commented Jun 21, 2017 at 20:06

2 Answers 2


The humidifier works well in the basement. Two ideas:

  • If the humidifier's capacity is adequate and the basement is connected to the HVAC system (vents and a return, and ductwork shared with the main floor), run just the HVAC fan continuously to circulate the house air and let the dehumidifier dry the air for the whole house.
  • Otherwise, get a second dehumidifier for the upper level. I see isherwood commented a similar idea while I was writing this. If you can set the dehumidifier on a counter next to a sink, you're in business, just like the basement. If you don't have convenient counter space, you could set up some type of surface next to the sink that is higher than the sink and run a discharge hose into the sink. If that isn't a good option (sink height is typically higher than normal table height), you can still do it using a condensate pump.

    You don't describe the exact setup for getting the water into the drain in the basement. Dehumidifiers typically have the ability to connect a hose to the collection tray. Use adapters to connect a piece of vinyl tubing to that tray drain.

    Run that tubing into a condensate pump (http://www.homedepot.com/b/Plumbing-Pumps-Utility-Pumps-Condensate-Removal-Pumps/N-5yc1vZbqoh). You will need to raise the dehumidifier so the collection tray drain is higher than the input hole in the condensate pump and keep the tubing short enough so it is a straight shot and doesn't dip a lot lower (set the dehumidifier on a small stand or table). Run the condensate pump discharge to a sink.

    I've done that in an enclosed crawl space connected to a basement and it works well for unattended, long-term use.

  • There is no HVAC system in the house. Heating is all electric (yea, crappy). In the basement - there is a drain hookup for the washing machine. I setup the dehumidifier higher that the drain access point and the drain hose from the dehumidifier goes directly into the drain access which leads to the sewage/septic connection. I guess I really should just get one for upstairs and leave in running on the kitchen counter and drain into sink when we're not here.
    – Vasuvius
    Commented Jun 21, 2017 at 19:59
  • You could install a window A/C unit that would be just large enough to offset the heat from the dehumidifier or large enough to cool the house. also, I bought a G.E. dehumidifier from Sams club rated at 70 pints of water per day. It came with an internal pump and tubing that can be routed to a drain. As others have said "you can not open windows for venting and expect the dehumidifier to reduce the humidity inside the house.
    – d.george
    Commented Jun 21, 2017 at 23:32

Two more ideas for you to consider: a cheap one and a fancy one.

Cheap first: add one or two fans to circulate the air in your house. Blow dry air from the basement up to the upper floor and see if that helps even things out without adding a dehumidifier upstairs.

Expensive: add an air conditioner. You probably don't care about cooling much of the time, so maybe you can find one with a humidistat. There's a range of solutions here from window units set to a relatively high temperature, to mini-splits which can be an economical permanent option, to full ducted central AC.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.