Health

19 Tips On How To Reduce Home Humidity

You know it when excess home moisture raises its ugly head.

You’ll spot foggy windows, smell a mildew or musty odor, or your skin feels clammy.

If it has been around for a while it had the chance to mark its territory. Damp spots, mold, and rotting wood are signs the soggy enemy is taking over the place.

But even if there are no indications (yet) your home’s atmosphere is too humid it’s wise to measure and control because..

  • it will make you feel better both physically and mentally (studies show that how happy you feel is directly linked to humidity levels) and,
  • keeping more money in your pocket due to reduced heating bills is also a nice reward.

So how to reduce home humidity levels?

Often, simple measures can make a big difference. In other cases more drastic actions are necessary.

Here’s an overview of simple tips and more radical solutions on how to combat excessive indoor humidity. Easiest applicable measures are mentioned first.

 

How to Lower Home humidity?

Do It Yourself Magazine April 1965 Beat CondensationThere are ways to lower the humidity once you become more aware of what is raising the level in the first place.

Actions

  • First and foremost, ventilate. Especially the areas that create moisture, like the kitchen and bathroom. When vent fans are present, make sure to turn them on and/or leave them on longer. Especially in the kitchen, bathroom, and basement. If not, consider having them installed by an electrician.

Cooking as well as showering but also washing machines and dryers affect the amount of moisture found in the air, especially when people take long, hot showers.

  • If you do not have exhaust fans or a ventilation system, you can crack a window for a few minutes to dry the air out, especially in the bathroom areas that tend to hang onto additional moisture for longer periods.

Mathematically speaking, it only takes between four and six pints of water to raise the humidity level inside of 1,000 square feet from a mere 15% to 60%.

The amount of people within the home can affect how much humidity is in the air as well. One person breathing produces about ¼ cup of water within an hour’s time.

  • Ensure that exhaust fans in kitchens, bathrooms, and laundry rooms vent to the outside. Installing vents and attic fans can help too.
  • Increase indoor temperature because warm air can hold more moisture (relative humidity decreases if temperature increases).
  • Use fans to increase ventilation
  • Take colder, shorter showers.  Use a low flow showerhead or shower under a less powerful stream by not fully opening the tap. (personally, I find showering with the tap partially open just as pleasant)
  • Becoming mindful of the indoor and outdoor temperature also can ease the concern of proper humidity within the home. What is the current temperature inside versus outdoors?
  • Are you keeping your home much cooler than the suggested temperature? If that answer is yes, then minor adjustments to the humidity level are easily adjustable.
  • Run the AC. Since this option is costly other possible measures are preferred.
  • While cooking, try to cover your food and take full advantage of the exhaust fans in which your home is equipped. Oven and stove-top cooking produce more moisture. Slow cookers contribute less to indoor humidity.
  • Vent clothes dryers outside.
  • If there is a humidifier or vaporizer in the home, turn it off for a little while or simply turn it down. Most humidifiers or vaporizers on the market today have a turn dial, or button to adjust the level of vapor or water you would like dispersed into the air. (a no-brainer but added for the sake of completeness)
  • It’s recommended to only use induced draft, sealed-combustion, or power-vented boilers, furnaces, and water heaters.
  • Air-conditioning drain lines and drip pans should be kept clean and unobstructed.
  • Temporarily place house plants outside or concentrate them in one room. Plants release moisture vapor to the air. Especially when you have lots of plants their role in home humidity levels can be significant. Also make sure not to overwater them.
  • Freshly cut firewood contains large amounts of water that evaporates when stored indoors. Better keep it outside.
  • Keep downspouts and gutters clean. Adjust downspouts so they carry water farther from the house. Restrict watering plants to bare necessity.  Prevent water from pooling at and around the foundations by a descending surface.
  • You may also want to use a dehumidifier if maintaining your humidity has become an issue or you live in an older, less ventilated building. Dehumidifiers are commonly placed in basements, since they are underground and do not get a lot of warmth or direct sunlight, or in bathrooms without windows or specific areas in the home that require moist removal. Dehumidifiers work best with closed doors and windows. In order to ensure proper circulation dehumidifiers need to be placed away from walls and furniture. Except for models that have an air vent on top.

 

Types of dehumidifiers

Various dehumidifiers exist. From small portable devices to large whole-house dehumidifiers utilizing basically three different technologies.

  • Desiccant dehumidifiers use desiccants which are substances that naturally absorb moisture (i.e. the little packets of silica gel included in electronics). Best for lower temperatures and moderate humidity. Can withstand freezing conditions as no water is produced. A well-reviewed unit is the Eva-dry Renewable E-333 Wireless Mini Dehumidifer.
  • Mechanical /Refrigerant dehumidifiers essentially work like your home’s fridge or airconditioning. Air passes across a cooled metal plate (coil) condensing the airborne moist which then drips into the water tank. Contrary to an AC these units slightly increase air temperature. Best suited for moderate to high humidity levels and moderate to warm conditions as this type of humidfier does not work well in cooler conditions. A popular choice is the best selling Frigidaire FAD704DWD Energy Star 70-pint Dehumidifier.
  • Peltier dehumidifiers are usually recommended for small areas such as average size bedrooms, bathrooms, but also RVs and closets. Although they are somewhat less energy efficient these units are valued for being quiet and efficient. Recommended product using peltier technology: Gurin Electric Compact Dehumidifier

 

Structural measures

Things to adjust in and around the home.

  • Carpet may retain moisture. If you’ve tried many things perfusely, consider replacing the carpet. Another benefit, humidity-thriving dust mites love carpet.
  • The addition of tubular or wrap insulation on pipes will also help. Insulating tubing for cold water pipes help decrease “sweating”.
  • Due to the warm surrounding air, and the cold water of the tank and pipes, toilet tanks and water pipes are another source of condensation. Adding a mixing value to the water supply line and rigid waterproof insulation on the tank, will reduce these effects.
  • Cold surface moist can be controlled by adding storm windows, plastic film on the windows, making any repairs to windows or window frames, installing weatherstripping and caulking both inside and outside of the window. This will prevent cold drafts and lower heating costs.
  • Vinyl wallcovering and other impermeable wallcoverings can trap moisture as well as keep it out. When moisture is trapped this can lead to mold growth.
  • Insulate crawl spaces with a plastic vapor barrier.
  • Concrete basement walls can be a huge source of excess humidity. If they haven’t been waterproofed from the outside you could try to waterproof them with products such as Xypex or Drylok. Results however are uncertain. Repair wall cracks.
  • In order to have rain water flow away from the house ensure that the yard next to the foundation slopes away from it (generally at a rate of 1 inch per foot). This helps prevent water to enter crawl spaces and basements. This, however, does not solve the problem of ground water that’s pressuring its way up trough the basement flour and walls if these are not sufficiently waterproofed.
  • To battle moist coming from the basement floor consider having a sump or a French drain installed. A sump is basically a hole with a pump in the concrete floor. A French drain, or perimiter drain is a piping drain system that’s an extensive version of the sump.
  • Have your foundation treated with Hydroclay (the stuff that’s used to waterproof tunnels). This water absorbing clay seals the basement in the areas where the water infiltrates.
  • Loose shingles and flashings may leak rain into attics, walls, insulation and other areas. Inspect the roof yearly to avoid such leaks.

 

What to do with humid crawl spaces?

Bare earth flours are a huge source of moisture. As moisture evaporates from the earth, houses built on such crawl spaces will experience higher humidity levels. Using a vapor retarder (polyethylene or heavy plastic sheets) as a ground cover in crawl spaces will prevent moisture problems. If a vapor barrier is not used, this humidity can become a breeding ground for mold, fungus, mildew and a host of other problems.

Proper crawl space ventilation is also essential.

  • When there’s no vapor retarder, 1 square foot of free vent space is required for every 150 square feet of ground exposed crawl space.
  • If a retarder is being used, the numbers change to 1 square foot of vent per 1,500 square feet of covered, ground crawl space.
  • If the crawl space vents include louvers and/or screens, the double the amount of ventilation is required to make up for the reduced air circulation.

 

What you should know about dehumidifying house plants

You may have heard about houseplants that are known to absorb moisture from the air. Tropical plants called epiphytes such as English Ivy, Peace Lily, Reed Palm, Boston ferns and Tillandsia are plants that get all their water from the air instead through roots.

They are often touted as house plants that filter the moist out of the air thus reducing hazardous humidity levels in you home.

But you know what they say, if it sounds to good to be true…. it probably is.

All plants give off more water to the atmosphere than they absorb. Think about terrrariums and greenhouses where the air is always humid. So contrary to what is sometimes claimed, these plants are not natural air dehumidifiers. At most they add less to humidity then other types of plants.

 

Do not underestimate the importance of proper humidity levels

Improper indoor humidity levels are a common home hazard that is often underestimated. Dust mites and other sickmakers such as allergens, pathogens, and noxious chemicals are more abundant in humid conditions.

Allergies, headaches, asthma symptoms such as wheezing, shortness of breath or a chronic cough also indicate you could benefit a lot from lowering moist content in the indoor air.

Dehumidifiers, ventilation, air conditioning, humidity monitors, weatherstripping, caulking, insulation, interior adjustments and lifestyle changes can all help ensure ideal home humidity.

These actions may involve some costs but in the end they will safe you money and improve the health of you and your family members.

Don’t forget, ideal humidity levels for your home are less than 60% in the summer and between 25 40% in the winter.

  • The bedroom requires about 50% relative humidity, all year round to reduce dust mites and allergens (source: PubMed.) Proper humidity levels, in other words, sufficient moist, is easier on your mucous membranes and experts claim it helps you sleep better too.

Got rooms in the home where the opposite (too dry air) is at play?

 

31 Comments

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  • Reducing humidity is always a challenge especially for moms out there. Aircons, fans or evaporative coolers are the best option for appliances but still also depends on good ventilation.

  • We (wife & I) are 10+ years into experimenting with low RH % (upper 20s to low 30s) to alleviate wife’s “hot flashes” in our house. Our Santa Fe Rx (PN 4023673) dehumidifier maintains the RH % in our open LR-DR-K area usually from 26 to 30 %, except when the condensate pump fails due to being overworked – on our 3rd pump with other 2 being used for parts.

    As long as RH is below 32% she is “flash” free.

    Until this year our adjacent bedroom was from 28 to 32 % but the shutdowns this year have allowed the bedroom materials to re-humidify and now we can get only 35 to 40 % there. Preparing to buy a constant drain smaller dehumidifier for the bedroom but not sure of their low capabilities with their electronic controls. Our Santa Fe unit uses a non-electronic dehumidistat that allows it to get into the low 20s if we want to. Electronic units only note to 30%.

    If anyone knows of a constant drain smaller (shorter than 24″) unit that gets 28 to 32 % RH please reply.

  • My parents have a house in the mtns of nc! This is a vacation home and they go abt 2 times a year! The basement has some moisture in the air! I know a dehumidifier would work but that as to be emptied! What can done year round to help with this

    • There are several continuous operation options, varying in usefulness depending on your parents situation. You could equip the dehumidifier with a hose to let the water flow into the floor drain or basement sink instead of into a tray or tank. For this you’ll have to place the dehumidifier high enough so that it uses gravity to drip the water into the floor drain.

      If you don’t have a floor drain or washing machine drain in the basement you could consider getting a dehumidifier with built-in condensate pump (continuous drainage option) which will pump water up to a sink or drain to a nearby room such as the bathroom or washing room.

      Another way to stop having to empty buckets is to get an add-on pump kit for your dehumidifier. For example this pump with vinyl tubing (make sure this setup fits your existing dehumifier). The humidifier drips into the pump and when the water level is high enough the pump will run until it’s empty again. Hope this helps.

  • Hi I’m Gerry,
    We purchase an older manufactured home in the Villages in Lady Lake Florida, its been empty for a while we just moved in and it full of moisture and musty smell, so we cleaned out everything and had the carpet steam clean got rid of the old furnisher that was in the house, the musty smell was gone ,2 days later its coming back, we set up the dehumidifier to take that humid out but theys know water accumulating in the tank , the laminate floor is damp like and carpet is a little damp as well. the temp is set at 74 right now but nothing seem to help, we thought of opening all the windows for a while to air it out , but afraid it s going to cause more humidity. don’t know what to do.
    help please> Sincerely Gerry

  • Hello everyone, just reading this useful article, and everyone’s comments, and wish to share a thought for you all, as here in the rural south of England and 30 miles inland, half way between the coast and London the humidity has been a constant average of 85-95% which at times is uncomfortable at the very least not to mention health related issues, I would highly recommend the use of an old fashioned open fire, it sucks out the existing damp air and heats up the whole room, the remaining home needs a gentle heating to the other rooms, I further employ the use of a marine engine heater, which consists of a electric powered oil filled tube, that’s placed under the bed, if I forget to turn it on well before retiring for the night, then the bed can feel damp and uninviting, resulting to the use of hot water bottles, and cups of hot chocolate, and then not to go into to much detail but a little bedtime passion, always guarantees warmth with sleep, and my wife says it helps her breathe better, as she suffers, with loss of breathe though the night. Her theory is it raises her blood pressure, resulting in stronger breathe control. She changes bedding each week, and washes walls ceilings, and windows with hydrogen peroxide, a solution she makes her self, ( she has a degree in science,) so please don’t start splashing it about before your a where of the facts. As it was Christmas I bought a dehumidifier (made in Japan oppersite to blunt) based on plasma technology, so hopping its the best, I placed our hydrometer in the bedroom on the head of the bed, it was reading 87% on the wall by the front entrance, I left it to adjust to the new environment and surprisingly in went down to 75% and remained at this, so after two hours turned on the dehumidifier and shut the door to the bedroom, and have not turned on the under bed heater, we retired to bed 6 hours later, hydrometer now at 55% and holding tank is half full approximately 2 pints..so it does work but have to keep doors shut…had it not worked I would have returned it back to the shop, in exchange for a sheep skin rug to go in front of the open fire, and sleep on that…wink wink.
    One last think on ventilation, whilst I know it’s important, there are times it needs to be closed due to it becoming a thermal bridge at due point, as in when the in coming air condensates, when hitting the warm air.
    So really is an exact science, with variables. Good luck it helps too!

  • Hi everyone great advice here. My question is last year we bought 11 Alside ultra max windows had attic reinsolated in hopes condensation would stay off windows with no luck we are wiping down windows everyday. We purchased a dehumidifier and run it constant. We are in the Minnesota cold so some of the moisture I get the majority I don’t. Do I need more insulation in the outside of house plastic on the windows? Feeling frustrated and needing answers..thank you.

  • Help me I just moved to Longview Washington from Denver Colo and having lots of hot flashes My home was built in 1910 but the owners before us updated this beautiful home but I have problems with the humidity in this home. I’m suffering with this manger problem. Please give me good advice to help me. Thank you .

  • This is a really great article, but please fix the typos of “moisture”. My OCD almost had me stop reading because the typos were that frequent.

  • Wow! Great information and tips right here. I was waiting when reading to stumble upon basement foundation and there it was! cracked foundations are a main contributor to moisture issues, if you have a basement of course. This was my problem for quite some time, until I finally realized what the problem was. Crack injections are cheap and easy, yet you need to ensure your service provider is utilizing the right tools and materials. Check this out here: https://staydrywaterproofing.com/services/foundation-repair/

    Many contractors and service providers of home waterproofing and what not, will often fill cracks haphazardly. Ensure the company you’re hiring uses the right stuff.

  • Running aircons emit HCFC’s and HFC’s and should be strongly discouraged wherever possible. The astronomical increase of these gases will destroy the ozone layer but nobody seems to be making a fuss about it.

      • We also don’t have a/c and live in the Midwest and are dealing with high humidity levels in pour home. We just purchased last December and during the summer on very hot days we close the windows and in the evening we open them to invite the sometimes cool air in. We use ceiling fans for air but noticed we have mildew in our kitchen cabinets and other places downstairs of our home. Our home is not conducive for central air we were told. We have to get a ductless system called mini splits but can’t afford them at this time. Any suggestions on getting rid of the mildew build up? Thanks in advance.

        • You might want to look at what HD has for your kitchen cabinets and other such places:
          Hydrosorbent Silica Gel Dehumidifier Dessicant Safe Pack
          Absorbs moisture without using electricity. Protects your Items by keeping them dry.
          Protects 33 cu. Ft. of space each. Reuse by heating in oven, etc.

          As described above, we use a whole house mechanical dehumidifier to lower our humidity to around 28 %RH and we live next to a river. We also use dessicant packs inside our safes.

  • Bought humidity unit for our basement. It removes large amounts of moisture from the air very quickly and noticeably improved conditions in our basement. This was a good value for us. It was exactly what we needed to bring the mold issue under control in our basement.

    • excess heat and very, very expensive. They definitely reduce the moisture.

      As an MD, it is important to know that mold is causing a lot of unnessary medical issues. I suffered 5 months from a rash that 7 dermatologists could not solve. They all said it was contact dermatitis and not one suggested a mold allergy. I spent hundreds of dollars on creams and ointments they prescribed, changed all my laundry detergent. Thought it might be mites, poison ivy, etc. If you go on line, you will find thousands of people who are suffering from imaginary bugs they feel crawling on them. ITS MOLD!!!. I discovered the mold through testing. Had it remediated, and now rash has gone.

      • Your mold allergy might also be a sign of overall decreased immune health and ultimately, gut health. “Leaky gut” often leads to skin rashes and fatigue. Should your rash reappear, or you have other symptoms like decreased energy or brain fog, seek out a chiropractor or M.D. who works with functional medicine/nutrition to restore your gut health.

  • Our home always has high humidity. We use a dehumidifier every day but it creeps back up to 60%+ often. We’ve had issues with mildew for years. Our house is over 50 years old with original Windows. Should we consider window replacements?

  • Great tips, Thanks for sharing valuable article. To prevent humidity from becoming a problem in my apartment in the first place, looks like we can take simple steps to reduce the amount of moisture that we allow into the air.

  • hiiee everyone… in Summer in poultry farms there is big issue to control humidity in sheds where layer chickens are present… so do anyone have idea how to reduce humidty in Poultry farm shed during summer..