RV Condensation

RV Condensation


We have been Full Time RVing since November of 08 and we love it. But we are in a very small 25 ft RV, and the moisture on the windows is killing me.

We have no leaks, I feel its just the cooking, showers and breathing that creates the condensation. I don't think we are ready to give any one of those up.

Do you have a suggestion? Hope you can help. I look forward to hearing from you.


Comments for RV Condensation

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Jan 29, 2018
Mold and mitigation
by: Karen

Hi, I am writing because there is a major mold issue in our 2016 Rockwood in which we live. I bought a dehumidfier early on, and have tried to keep walls, etc. wiped down.

PROBLEM: the couch area was such that it was impossible to get behind it for wiping. I finally determined that there was a mold issue behind the built-in couch and removed it. I have pulled up the carpet, cleaned underflooring with bleach,etc. but the mold is into the wood and I suspect the walls as well.

Suggestions? I have literally followed all the ideas listed: wiping, dehumidifier, open vents, use of stove fan, opening up the windows and door when weather allowed. I am not sure what to do at this time. New RV, mold, and no coverage from warranty (1 year) and doubts about insurance but will check that soon. Thank you for your ideas. Karen

May 09, 2017
Wet camper
by: Anonymous

We bought our camper last year 2016, we only got to use it once in 2016 and then had to put it up for the winter. We took it out of storage in April and went camping in May of 2017, it was raining very hard for two days so obviously we could not open the windows or vents, i found that are walls were wet i could literally wipe it down with a rag.

I need to know is this going to happen all the time it is raining? I did purchase a evadry dehumidifier for our next trip, I am now concerned for mold, can mold happpen that fast, and any feed back would be great. thank you.

Jan 23, 2017
by: Anonymous

When finishing taking a shower make sure to wipe done the entire inside of the area with a car chamois. These are great for your car and the inside of the shower removing just about all of the water. Reuseable and washable, will help for sure.

Oct 03, 2016
Lou from Van
by: Tordon

From the sound of things, you took some great steps to help reducing the humidity in your RV. Unfortunately, here on the West or "Wet" Coast, the humidity levels remain very high for long periods of time, especially throughout the winter. Because of this, it doesn't allow you to take advantage of the best way to get rid humidity, air circulation. When the humidity outside remains high for weeks or months, it can be very difficult to rid yourself of the normal moisture found in the air, not to mention all the excess humidity added to the air through cooking and showering.

My partner and I lived in a 22' RV in Victoria for 4 months during the summer and into the fall. Come October, the humidity was getting so bad in there that we abandoned it to live poshly in a wood heated house. Heat from a wood stove is a great way to dry spaces out but propane heat not so much as it tends to add to the excess moisture as well. Electric heat may be the next best thing. Also to note, I've seen mold growing in corners of heated suits in houses and in newly constructed houses built to code here in Victoria during the rainy season.

So to sum things up, without a way to rid yourself of the humidity created by living in a super small space designed for fairly short stays in high humidity conditions, mold is almost unavoidable.

Sep 26, 2016
Hearing loss due to mold in air conditioner system
by: Anonymous

We have been living in our 24' motorhome for a year while we are building a house. The summer has been extremely hot so the air conditioner is on all of the time. I developed hearing loss, and was not sure what the cause of it was. After 4 doctors just said it will go away in 2-3 months and prescribed meds for the condition, the next doctor to see me said it was caused by mold. Due to the enclosed area in the motorhome.

Now we have to remedy the problem and hopefully my hearing will return.

Feb 20, 2016
Mildew and condensation problem
by: Lou_in_Vancouver

We have been spending our winters in Vancouver, Canada and this is the first year we've had this problem. It rains a lot here in winter but it doesn't really get much colder than 0 - 10 degrees Celsius or around 32 - 50 degrees Fahrenheit.

This winter I decided to try something different. I skirted the underside (outside) of our 5th wheel with vapour barrier and 1 inch rigid foam insulation, put some window film on all the windows, installed 3 Dri-Z-Air 'dehumidifiers' and had the carpets professionally cleaned (not with a steam cleaning machine though).

We are always finding condensation dripping on the walls but worst of all is the mold. I discovered it first in the corners of the shelves, and then found it on some clothes, and today I found it all around where the carpet meets the walls. GROSS!!! What did I do wrong?

Dec 05, 2015
by: MIlitary Molded

Started experiencing the mildew issue about a month ago in the Pacific Northwest when our 2015 White Hawk started being used as a temp full time home.

How worried should i be. Its disappointing to say the least. Its a brand new rig, our first. If this will be an enduring issue, I am developing reservations about if its worth the time and money to own one of these things.

Any advise Rv'ers....?

Sep 12, 2015
Make use of dehumidifier water
by: Anonymous

You can use the water that collects in the dehumidifier pan as toilet flushing water when you're boon-docking & running off of a generator and no fresh water hook-up, like we are doing.

Sep 18, 2014
EVA-DRY 1100
by: Anonymous

We live full time in our rv for 8 years and run 6 to 7 Eva dry
1100 in the winter they work good all of then are full every other day. I also run 3 9 inch fans this works good.

Dec 15, 2013
by: RVAK

It is very important to keep the humidity level in your RV to around 40%. In the neophyte years as a traveler, I just wiped the windows to remove the moisture and was not concerned with all the humidity.

One year, after I noticed water running down the inside bedroom wall, I got concerned. I thought there might be a roof leak. I removed an air vent and looked in to the area between the ceiling and the roof (attic).

The underside of the roof was beginning to grow black mold. I purchased a dehumidifier, removed all the ceiling vents, sprayed mold control into the attic, and allowed the area to dry for 2-3 months.

I also cut three circular vent holes in the top rear of my trailer and in the plastic vent skirt in the bedroom vent to increase the air flow (as in a regular house attic crawl space).

I will never be without a dehumidifier again. Too much moisture is a serious concern. I have not had a problem since, and the windows never fog.

Dec 13, 2012
by: Anonymous

I have also found that if you put window film around the AC inside it helps with air coming in.

Feb 17, 2010
RV Dehumidifier
by: Sharon

If you're short on save inside your RV Dometic Corporation has the first ever Dehumidifier Air Conditioner combo rooftop unit specifically designed for RVs. It's an 11,00Btu unit that can remove up to 12 gallons of water from your RV every 24 hours. You can adjust it from 35 to 70 percent to personalize your comfort level.

The unit is also eco-friendly using R-410A refrigerant which releases heat better than R22.

The RV dehumidifier operates with Dometic's Comfort Control Center II and is powered by 120-volt-AC and a 3.5kilowatt generator when used with electrical hookups. A larger generator is necessary when boon docking.

The unit is currently selling for around $1,159.

Jan 27, 2010
An additonal thought
by: Andy & Bobbie Harley

On the dehumidifyers you could add a drainage tube to drain to the outside and save the hassell of having to deal with emting the drip pan & it would emidiately exspell the moisture out of the rig.

Jan 27, 2010
by: Will Imanse

We use a full sized home type dehumidifier. When we first put it in we were having to empty it everyday. It has a 3 gallon tank. Yes you read that right, the unit was collecting 3 gallons of water a day for the first couple of days. A lot of that water would have been in the walls, carpet, our stored clothing, upholstery etc. After about three days the RV started to feel a lot more comfortable.
As an added side benefit the Dehumidifier puts out a small amount of heat as a byproduct. We find that it is enough to keep our inside temperature about 10 degrees Centigrade (18 Fahrenheit)above the outside temperature. This also means having to run our furnace a lot less.
We keep our dehumidifier under our dinette table. About the only time we have to move it is when we have company over for dinner, and we need the extra leg room.
Maintenance is minor, and involves having to take out the air filter every 3 months or so and vacuuming or washing it. Otherwise we just have to make sure that the unit does not freeze up, when this happens a block of ice forms on the coils and it effectively stops working. For this problem we just turn it off till the ice melts and it is ready to go again. We have found that the unit will only ice up if the ambient temperature in the rig gets below about 15C or 60F.
Will Imanse

Jan 27, 2010
Plastic Window Kits
by: Sharon

If you have single pane windows on your RV they won't be as effective at keeping the cold out.

Adding plastic films on the inside of your RV can help keep out the cold and reduce condensation.

Look for vinyl, polyester or polyethylene which is available in several thicknesses. Thicker plastics will be more expensive, but easier to work with and will last longer.

Home Depot has clear plastic window kits that stretch to fit when heated by a hair dryer. I've used these myself and they are very effective at keeping out the cold.

Jan 26, 2010
How Fight Condensation Your RV
by: Sharon

RV Condensation on your windows happens when the warm, moist air inside of your RV comes into contact with a cool surface such as your windows. You can see it on the windows, but it may also be building up in your interior walls of your RV. This can cause mold and mildew that would be very harmful to your health.

You are right that the moist air forms from cooking, showering, hot water dish washing, and just plain breathing.

The most common way to reduce the condensation is fresh air exchange - by just cracking a window, exhaust fan or roof vent. Especially when you are creating significant moisture with any of the above tasks. So, if you're cooking and creating a lot of steam run your roof-exhaust fan and crack a window to reduce the moisture build-up.

If this doesn't reduce the condensation in your motor-home you could try using an RV dehumidifier. Eva-Dry makes an electric petite dehumidifier that doesn't use a compressor so it is quiet and lightweight. It will remove the moisture from the air in your RV and store it in a spill-proof reservoir. It will help protect you and your rig from mold, mildew and moisture build-up and can be used in any room where dampness and humidity is a problem. The Eva-Dry unit has an auto shut off, so if the reservoir is full it will turn off. There is also an indicator light that alerts you that the unit needs to be emptied.

A small unit like this designed for RV use can really make a difference in such a small space. I hope this was helpful. If anyone else has any suggestions, please contribute your tips.

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