Condensation problems with fiberglass walls?

[AuthorSP]

Hello, As we continue our research into Ollies and their less expensive/ less impressive competitors, we've been looking into the Casita. One of the biggest problems we see with that one is the carpeted walls and ceiling. That just weirds us out. Not a fan at all. I understand why the did it- they are a single hull. They also claim it insulates and sound dampens, but I imagine it also gets dirty and holds smells easier, too. The one good argument they offered was that it prevented the condensation problems common in boats and campers with fiberglass walls. I understand this is enough of a problem that Oliver sells matting to go under cushions to prevent mold, but I have 2 questions:

1) How well does the matting work?

2) How much of an issue is condensation, with or without the matting? Is it dripping from the walls?

[Frank C]

The Oliver is pretty airtight because of the double hull construction and insulation, and the fiberglass interior surfaces don’t absorb moisture like carpeting or wood products do in other trailers, so with the windows and doors closed, managing interior moisture from showers, cooking and breathing is something that most Oliver owners have methods to deal with it.  Condensation on the interior walls can occur with big temperature changes unless you use some easy solutions. Not severe condensation (we’ve never had it “dripping from the walls”), it’s more just that muggy uncomfortable high humidity feeling.  But condensation can happen under certain conditions. Using the air conditioner or furnace can help depending on ambient outside conditions.  Some use small dehumidifiers, others (including me) use DampRid, and some will run the MaxAir fan frequently, even with the furnace or AC running, just to get more air exchange.   Always use the exhaust fans when using the shower or cooking.  And someone posted this graphic to illustrate where the moisture typically comes from.   As the old expression goes “we have met the enemy, and he is us”.  And we have the hypervent matting and it’s worked great so far.  No problems with moisture under the mattresses. 

[TexasGuy]

So I visited Casita and had the same reaction the carpet.  I just could not get past it and white color looks like a huge dirt magnet.   We have had some pretty humid days this summer in Dallas and when I check on trailer at storage facility no issues with condensation even before I put up a damprid in closet.   I don’t run any fans or have vents or windows open.  The hypervent seems to work really well. I have not seen any moisture under the beds.   
 

If there was any issue while on road fiberglass hull very easy to wipe down. I have had windows fog in mornings and running maxx fan quickly takes care of that   

 

[Overland]

I agree with Frank and his extremely large map.  Moisture is something you'll have to deal with in any trailer, but I wouldn't say that it's problematic in an Ollie to any degree.  My opinion on the mattress pad was and is that condensation is entirely an issue with the optional perforated latex mattress.  I think that the perforations give body moisture a direct path to the underside of the mattress, where it can easily condense.  We never had a problem with a different mattress, nor with the cushions that we switched to later, and the only people who ever reported a problem had the latex mattresses.  So, I'd say that if you get the latex mattress, then definitely get a pad; but if not, then don't worry about it.  You can also use a cheap thermarest pad or something similar rather than Oliver's rather pricey option.  Unless it's standard now - may be.

What we did find, though, is that when I sleep, I'll end up with my back against the side wall at some point, and so I'll get condensation there on the wall - enough to wake up with the sheets wet.  I solved that problem by just just sleeping with the back cushions in place and that's plenty of insulation to prevent condensation, and still leaves plenty of width for me to sleep comfortably.  That's the extent of any moisture issue that has required more thought from us than just a little ventilation.  Also, Oliver has improved the insulation since our trailer was built, so a newer one might not have the same problem.  

So in general, unless it's just super cold out, we'll have a window cracked and that's been enough that we won't see any condensation except when cooking or showering.  And running the max fan on its lowest setting and running the bath fan for a minute after showering easily prevents condensation from those two activities.  I don't even think the mirror door fogs up when we shower, so that's pretty good.  I'll leave the bath door open and the bath window cracked when we're gone for the day to remove moisture from the shower drying out.  I also tend to wipe down the shower with a squeegee and towel after showering, which gets rid of a lot of that.

I suspect that Casitas do have condensation, but it's under the carpet so you can pretend it's not there.  😁

[Galway Girl]

The under mattress material would be used on any trailer.   When you sleep on a mattress with a box spring in your home the moisture from your body seeps down through the mattress and dissipates within the box spring.   When you have a mattress on a flat surface, you'll see that the moisture eventually collects on that flat surface.   So in the case of Oliver they offer a material the allows air-flow between the bottom of the mattress and the platform.   Some folks install a froli system which acts as an air gap.

As to the rest of the issues you saw with Casita, we also had that reaction from Bigfoot Trailers and Escapes which are all single wall.

We have minimal condensation issues with walls, and as to the mattress we bought the optional material from Oliver and it works like a charm.

C Short

Hull 505 

[John E Davies]

This issue depends a WHOLE lot on where you live and camp. Around the arid parts of the West  it simply isn’t a worry because the humidity is so low outside. However, you should never button everything up tight.There are a dozen 1/2” moisture drain holes in the belly of an LE2 which are always seeping in some fresh air. But even on super cold or super hot days you should have some sort of forced or convective ventilation operating to extract moisture. Cracking a roof vent and a side window is enough. If you live where it rains often, or camp in the dead of winter, this is a lot harder to do. For sure, if you are showering or boiling a pot of water, there should be a fan running. And stop breathing, that will eliminate a lot of moisture……😬

John Davies

Spokane WA

[Mike and Carol]

Agree with comments above.  Ventilation is the main preventer of condensation.  We keep a vent open almost all the time and have had very few issues with condensation.  We shower, boil water for coffee, cook and even breathe inside our trailer.  Mike

[AuthorSP]

Thanks, all. Good information!

 

[KenB]

52 minutes ago, Overland said:

the only people who ever reported a problem had the latex mattresses.  So, I'd say that if you get the latex mattress, then definitely get a pad; but if not, then don't worry about it.  You can also use a cheap thermarest pad or something similar rather than Oliver's rather pricey option.  Unless it's standard now - may be.

I have the standard mattress with a topper over it and have problems with condensation underneath.  It's not just restricted to latex mattresses.

Minnesota fall camping is worst for under mattress condensation, but it can occur anytime when the conditions are right.  Cool hull and several blankets on top of me holding in moisture seem to make it most likely to occur.  When I'm solo I sleep on the curbside of our twin bed E2.  The water heater and furnace (if its cool enough to run it) under the bed keep the fiberglass under the mattress warm enough to keep the condensation under control.

Water has condensed on the wall a few times next to me while sleeping, but nothing like the regular condensation I get under the mattress.

Update-  Just went out and lifted the mattress after camping last night.  There is condensation underneath.  Temps were in the high 60's-low70's  Roof vent fan was running on low all night.  One window cracked.  One light blanket half on me.  Top and bottom sheet.  Rained yesterday afternoon.  I need to put an old camping mat under the mattress and give that a try.

So it's not just the latex mattresses.  My 2018 also has regular issues.

[Overland]

Interesting to hear and certainly willing to change my mind - but I have to say that sounds like an excessive amount of moisture with temps in the high 60’s and good ventilation. Since you said it rained yesterday, are you certain you don’t have a small leak?  Water from the Ollie light will end up under the bed and three years is about when mine needed to be recaulked. That’s how I spotted my leak - just damp under the cushions like condensation. 

[topgun2]

Instead of purchasing what I thought to be rather expensive materials to insulate my mattress from both the bottom and the walls - I went down to Lowes and bought a sheet of 1/2 inch foam board.  I cut a piece for the bottom and then cut other pieces to rise about 6 inches up the wall.  That is just enough to reach to the top of the mattress without actually seeing it under normal circumstances.

Since I never really had a "problem" with condensation prior to using the foam board I can't really say that it has or has not had a material effect on the condensation.  But, when in the middle of the night my "butt" slides over to the exterior wall, I'm certainly not jolted awake by the relatively cold wall.  Given the relative cost of the foam board versus the alternative solutions, it has certainly worked for me.

Bill

[Ray and Susan Huff]

2 hours ago, AuthorSP said:

Hello, As we continue our research into Ollies and their less expensive/ less impressive competitors, we've been looking into the Casita. One of the biggest problems we see with that one is the carpeted walls and ceiling. That just weirds us out. Not a fan at all. I understand why the did it- they are a single hull. They also claim it insulates and sound dampens, but I imagine it also gets dirty and holds smells easier, too. The one good argument they offered was that it prevented the condensation problems common in boats and campers with fiberglass walls. I understand this is enough of a problem that Oliver sells matting to go under cushions to prevent mold, but I have 2 questions:

1) How well does the matting work?

2) How much of an issue is condensation, with or without the matting? Is it dripping from the walls?

We have yet to see condensation dripping from the walls.  While traveling from Hohenwald to Oregon on our trip home from mid-December delivery, we expected to see condensation as temps were nearly always at or below freezing.  There was condensation on the windows in the morning, but no more than we have experienced in previous RVs.  We ran a space heater most nights and provided ventilation (see next comment).  Note that we were at high elevation most of the trip (I-40 Texas Panhandle, NM, AZ to S. CA), had no rain, and outdoor humidity was quite low.

Ventilation is key to keeping interior humidity in check.  At night, we crack a window, front and rear, and leave the ceiling vent open.  You could also run the vent fan on exhaust (pulling air out).  At the lowest setting (10%) you hardly hear the fan, and it uses just a few amps.  Definitely run the fan (on air out) while cooking or using the shower.

We did purchase this mid-sized dehumidifier, not knowing if condensation would be an issue.  We took it along on the trip home from Tennessee, in case needed, but did not use it; while on the road, condensation was manageable with heat and ventilation.  Perhaps it would have been more problematic if we were spending more time inside, but the majority of the trip was on the road; it's nice that you can leave the MaxxAir fan vent open while traveling. 

When we arrived home it was raining with 85%+ humidity (PNW).  Once she settled in our driveway, the Ollie's interior humidity was in the upper reaches of desirable (I don't recall exactly, but near the outside humidity).  We utilized the dehumidifier, propping the mattresses on their sides to prevent moisture collecting despite the fact that we have the hypervent mats (more on those later).  In two days the humidity was in the 50% range.   Since then we have controlled humidity without the use of the dehumidifier.  I did hang a dehumidifying pouch in the closet and a tub of dehumidifier crystals in the basement.  Now that summer has arrived, the cabin humidity has been satisfactory just with the vent and windows open.

I suppose you could use the dehumidifier while camping, but unless weather conditions are extreme (mostly in regards to freezing temps) humidity can easily be managed with ventilation and heat; we like to keep our travels as fuss-free as possible.  While closed up for periods of inactivity, the dehumidifier is good insurance against condensation issues.  Realize, however, that most of the surfaces inside the Ollie (unlike other RV interiors) are impervious to moisture, the mattresses/cushions being the most vulnerable.  This is why condensation is more evident than it would be in an RV with wood cabinets, carpet (walls, floors, and basements), and wallpaper, all of which absorb a fair amount of accumulated moisture.  Cushions can easily be brought indoors for storage; the mattresses not so easily.  Here lies the necessity for the Hypervent pads under the mattresses or sleeping cushions. 

Hypervent mats:  While I understand the concept, I question the effectiveness of this option.  In theory they give some ventilation between the mattress and the fiberglass bed platform, but is some of that moisture retained in the mesh of the mat?  If so, the mats would need to be removed and aired out occasionally - a great inconvenience during longer road trips.  My experience, as the "maker of the beds", is that they are a daily annoyance as they make it difficult tucking in bedding, especially between the mattress and the outside wall which has a narrow strip of mat.  They also make it more of a struggle to get into the under bed areas, such as to access the basement from inside or manipulate the water system valves.  These would be less noticeable with the standard sleeping mats than with the KTT mattresses, which are quite heavy.  We might try, on our next camping trip, not using the mats in order to come to a more conclusive comparison.  I know Hypervent mats are routinely used in marine applications, specifically fiberglass live-on boats.  Perhaps someone here with boating experience can comment on their effectiveness.

During storage, we routinely prop the mattresses up on their sides to reduce the chance of damage to the mattresses from moisture induced mold.  We also remove all fabric items that can draw moisture and become "musty".  The good news is that moisture damage to a mattress is easily, though not cheaply, remedied.  Not so with moisture damage to wood, carpet, and other surfaces in the "traditional" RV.  Side note: perhaps a moisture barrier mattress protector is another solution, though I can't attest to the effectiveness of such. 

It looks like you have received a lot of valuable input from other forum members.  I have not had a chance to read these yet, so please excuse me if I repeat some of their comments.  My final advice: I would not let concerns of condensation sway your decision to purchase an Oliver.  Condensation is problematic in all RVs - it's just more apparent with Oliver's all-fiberglass molded interior.  In reality, moisture is probably more easily managed and less damaging in the Oliver than in traditional RV interiors; search the Internet for wood structural damage in RVs.  We have friends who just purchased a small 2005 Big Foot (another molded fiberglass trailer).  The dealer had to make $8,000 in repairs to replace a majority of the floor which rotted out as the result of a leaking window!  Just one of many reasons people choose to pay a premium price for an Oliver. 

Our plan is to utilize dehumidifying crystals during short down times and the dehumidifier appliance for long term storage.  Once our Ollie has experienced a long storage period, I will update my opinions on The Effects and Control of Humidity in a Mostly Fiberglass RV Interior - sounds like an Oliver white paper to me.

[KenB]

On 6/29/2021 at 10:52 AM, Overland said:

Since you said it rained yesterday, are you certain you don’t have a small leak?

It’s not a leak, it’s condensation.  The area of condensation is roughly in the profile of a body.  I’ve tracked down leaks that landed under the mattress before.  It’s not that.

Last night was another data point.  No rain.  Indoor recording thermometer registered a low of 67 degrees inside the camper.  Roof vent running on low all night.  Fan on night stand running on medium all night.  The window next to the bed wide open.  Blinds open.  Dinette window wide open.  I slept in the street side bed.   There was condensation under my mattress this morning.  I’m certain that if I moved to the curb site mattress tonight I’d have condensation under that mattress on that side instead.  It’s not a leak.

We used to have a hybrid camper with tip out bunks on the end.  With nothing but cool air under the bunks when set up, that setup was a condensation capturing machine.  The Oliver comparatively captures a fraction of the condensation.

My point is that even the standard cushions will allow condensation to form under them nearly year round for me.  It’s not limited to the latex mattresses.  Ours are the standard cushions.

HTH, Ken

[Overland]

Thanks Ken.  I appreciate the correction.

[Jim_Oker]

Another PNW resident and camper here. I agree with comments above that  ALL RVs have  potential for condensation problems - the nice thing with the Oliver is  that the extent of the problems can be more quickly noticed. That said, thus far even camping during cool wet weather out at the Pacific coast in the rainforest, the  most we've seen has been some fogging of the windows overnight. We have the  KTT latex matress option plus the  hypervent pads and while yes they're slightly more of a hassle than a heavy mattress alone I haven't found them to be that  troubling - the thick heavy mattress is the main  thing making it a chore for me to get in those compartments but so worth it for the comfort (I'm quite certain we would not like sleeping on the base/stock cushions given  the feel of the  dinette cushions which are on my "to do list" to replace with something more beefy btw as I don't love them even for sitting on).

Anyway, we've not seen any condensation beneath the mattresses and the bit  of fogging  of the windows in the  early morning  has  gone away quickly during  the day. And we've only noticed the  window fogging on particularly wet and/or cold nights - less than we've typically seen in  our Class B camper van with its fuzzy walls and ceiling fwiw. 

We do keep a few windows and a roof vent cracked while sleeping (and turn on the fan  to 10-30% if it's feeling warm inside) and turn the fan to whatever level is required to keep the bathroom door mirror from fogging while boiling water or otherwise cooking  inside (most of our actual cooking we do  outside but have liked heating coffee water on the Oliver's stove in the AM). We run the bathroom vent fan and if needed the  MaxxAir fan during  and  for a little bit after showers and  I squeegee and  wipe the  wet bath's surfaces after showers to move that  water down  the  drain. 

We've also slept  in single wall tents which are way worse for condensation issues and from that you will necessarily learn a few things including that wet gear makes it worse as does "sleeping  hot" - if you  can  comfortably tolerate less covers over you you  will perspire less overnight and thus put off less water vapor into the  cabin. In any RV it pays  to think about  how to mitigate the amount  of moisture you  send into the cabin air and  what  level of ventilation you need for the significant moisture  you'll put in  there  despite reasonable mitigation efforts. To repeat - the design  of the Oliver simply makes it more likely you'll notice if you  could be striking a better balance there.

[Jim_Oker]

BTW I also have temperature/humidity sensors in  the  main cabin and  the bathroom cabinet as well as on both sides of the basement so I can  see if any spot is getting  unreasonably high humidity whether during storage at home or while camping. (we also have temp sensors in the fridge and freezer which  I've found quite helpful for  tuning the  temperature level as ambient air conditions, which  have  a big effect  on this sort  of fridge - much more so than a compressor fridge IME)

[Overland]

7 minutes ago, Jim_Oker said:

BTW I also have temperature/humidity sensors in  the  main cabin and  the bathroom cabinet as well as on both sides of the basement so I can  see if any spot is getting  unreasonably high humidity whether during storage at home or while camping. 

Speaking of that, I just learned this week about this company - Aqara - who make HomeKit hubs and accessories that aren't only relatively cheap, but are also getting good reviews on the Mac forums.  They have sensors for temp, moisture, vibration, etc.; as well as cameras, door and window sensors, etc.  All their stuff either uses coin batteries or are USB rechargeable, so they'd all work well in a 12v environment.  Add in an old iPad as a HomeKit hub and a wireless hotspot, and you could monitor most everything remotely, without breaking the bank (too badly).

[Jim_Oker]

Just now, Overland said:

Aqara - who make HomeKit hubs and accessories that aren't only relatively cheap, but are also getting good reviews on the Mac forums

Cool - thanks. The sensors I got are  just dumb sensors that broadcast to a little LCD base station display unit and show current conditions plus 24 hour high/low levels. I will look at those to ponder whether I want to bother upping  my game around sensors (i.e. would I view that  as  a "fun hobby"  or more of "chore"?). 

 

BTW one more thought for this thread. The Oliver is more like a fiberglass boat than any other  RV I've seen. I am pretty sure that  boats have all the issues RVs have with moisture and then some. It's a tried and true design  for such living/travel spaces.

[dewdev]

Hypervent matting is available from a number of vendors on Amazon at a more favorable rate. Only down side is you will need to cut the matting to size. A shart pair of sizzors work fine.

[Jim_Oker]

Yeah, good tip. I decided to just pay for the convenience to reduce the number of things I would  be doing myself to get the trailer tuned for our first  camping outings. I also priced getting good quality custom fit latex mattresses from a reputable local mattress place and found that the Oliver option was actually way less $$ believe it or not. 

[SeaDawg]

We don't have hypervent on the boat, or the trailer. We do either stack the cushions on end (short storage times, in season) or remove them, out of season. 

If I notice a clammy feeling or condensation, I prop the cushions up a bit during the day, so air can circulate. And, I don't cover the airflow space with bedding.

I've become a convert to microfiber, or at least a thinner cotton poly mix for sheets. They don't seem to transmit the moisture to the cushions, and dry very quickly. Blankets are all synthetic. Waterproof but supposedly breathable  mattress pad over cushions and topper.

As Jim_Oker said, at least you can see the issue and address it in an Oliver. It is present in all trailers, just hides better in fabrics, carpet, and wood in some others.

We've not had a lot of condensation issues, ever. But that really depends on where and how you camp, and weather, temperature and dew point.

[SeaDawg]

Btw, I wonder what the fabric content is in the current Oliver cushions. Anyone know?

My cushions were custom,  back in the day, and my fabric is a polyester blend (with I think nylon, definitely not cotton or rayon) Crypton commercial fabric that repels water and stains. I used a similar  Crypton  fabric and Ultraleather on the boat, last refit, with a breathable mesh bottom. I do think that helps, too. 

The Crypton stuff is antimicrobial,  and  anti mold, as well.

 

 

[Ray and Susan Huff]

9 hours ago, Jim_Oker said:

BTW I also have temperature/humidity sensors in  the  main cabin and  the bathroom cabinet as well as on both sides of the basement so I can  see if any spot is getting  unreasonably high humidity whether during storage at home or while camping. (we also have temp sensors in the fridge and freezer which  I've found quite helpful for  tuning the  temperature level as ambient air conditions, which  have  a big effect  on this sort  of fridge - much more so than a compressor fridge IME)

Remote temperature/humidity sensors are one of the best accessories for RVs.  We have a remote display with three sensors + temperature/humidity at the display.  One for the freezer, one for the fridge and one we put outside while in camp.  One reason I chose the monitor we have is because it displays all 3 + room temps on one screen without having to cycle through them on the display. 

How can you have as many sensors as you mention?  I thought of getting another set, but then some would be transmitting on the same channel; that's not going to work!  Do they make sets with more than 3 sensors?  

[Jim_Oker]

51 minutes ago, Ray and Susan Huff said:

How can you have as many sensors as you mention?  I thought of getting another set, but then some would be transmitting on the same channel; that's not going to work!  Do they make sets with more than 3 sensors?  

I got this base station plus two fridge/freezer sensors and 4 temperature/humidity sensors. It will support up to 8 sensors. 

https://www.amazon.com/Ambient-Weather-WS-08-8-Channel-Thermo-Hygrometer/dp/B00EW369VK

[Ray and Susan Huff]

10 hours ago, Jim_Oker said:

I got this base station plus two fridge/freezer sensors and 4 temperature/humidity sensors. It will support up to 8 sensors. 

https://www.amazon.com/Ambient-Weather-WS-08-8-Channel-Thermo-Hygrometer/dp/B00EW369VK

I'm going to get the WS-10 with three sensors and add how ever many more we need.  With this display, I can always see the fridge/freezer/indoor temps without scrolling, then scroll for other zones as needed.

I be able to use our Accurite 3 sensor unit at home and not need to swap it out for the trailer when we camp.

Thanks for your recommendation.