Foretravel Owners' Forum

Foretravel Motorhome Forums => Foretravel Tech Talk => Topic started by: DavidCindy on February 19, 2017, 11:48:38 pm

Title: moisture under bed
Post by: DavidCindy on February 19, 2017, 11:48:38 pm
We have a '94 U300 and have a continuing issue with moisture forming between the bottom of the bed and the engine bay plywood cover. I'm sure this must be an issue for others. Does anyone have a fix? We have just now laid down a 4 mil plastic sheet which we hope will be a vapor barrier of sorts. Thanks for any advice.
Title: Re: moisture under bed
Post by: John S on February 20, 2017, 06:16:19 am
We have never hasd that issue in any of our three coaches.
Title: Re: moisture under bed
Post by: Rich Bowman on February 20, 2017, 07:25:03 am
This is very strange.  We've never had a moisture problem.  I would wait awhile and then check the plastic and see if the moisture is on the top or the bottom because the plastic probably won't stop it but will tell you where it is coming from - the bottom of the mattress or up from the engine compartment.  If it is coming from the engine compartment, I'd want the vapor barrier on the bottom of the engine cover.  If it is coming from the mattress, I'd want to know why.

Rich
Title: Re: moisture under bed
Post by: John44 on February 20, 2017, 07:39:11 am
Is the coach sitting where it could be coming from the ground.
Title: Re: moisture under bed
Post by: Chuck & Jeannie on February 20, 2017, 08:05:56 am
Where is your coach located (i.e. what state or city)?  High humidity weather environment?  Been raining, or dry recently?

What kind of mattress?  Conventional spring, memory foam, "sleep number", old school air mattress?

What is the mattress cover material on the bottom side?

Does the moisture that forms have any color or odor?

When you lift the bed platform up, is there any sign of moisture on the engine side? 

Is this a new problem, or recurring?

Very strange...in 4 years on the Forum, first time I've read of this problem.
Title: Re: moisture under bed
Post by: rbark on February 20, 2017, 09:44:22 am
What type motorhome do you have?
Title: Re: moisture under bed
Post by: Chuck & Jeannie on February 20, 2017, 09:57:56 am
See initial post: '94 U300.
Title: Re: moisture under bed
Post by: NancyS on February 20, 2017, 10:25:58 am
It's condensate, cover the platform with indoor-outdoor carpet, worked for us.
Title: Re: moisture under bed
Post by: toyman on February 20, 2017, 10:39:13 am
Never experienced that in a MH, only in a boat. Here's what we used.
HyperVent Marine - Product Information (http://www.hyperventmarine.com/products.html)
Title: Re: moisture under bed
Post by: John Duld on February 20, 2017, 12:11:05 pm
What is the condition of the insulation on the bottom of the engine compartment cover?
Title: Re: moisture under bed
Post by: Texas Guy on February 20, 2017, 03:12:43 pm
As others have said, I have never heard of this before. If there is moisture it has to come from

somewhere. Condensation forms in a damp atmosphere on a surface that is cooler than the

air around it, as I understand it. Or moisture can come from a leak, water could be coming in

from the outside from an area that needs to be recaulked around the back of the coach. I hope

the vapor barrier will give you an answer. If you are in an warn, damp area check drain from the ac.

Carter-
Title: Re: moisture under bed
Post by: wolfe10 on February 20, 2017, 03:38:47 pm
This is not unusual in boats.  Cold water, warm bodies.  Condensation on the fiberglass below mattress.

Have not experienced it in a motorhome, but guess conditions could exist that could cause it.
Title: Re: moisture under bed
Post by: Jet Doc on February 20, 2017, 08:55:35 pm
This is not unusual in boats.  Cold water, warm bodies.  Condensation on the fiberglass below mattress.

Have not experienced it in a motorhome, but guess conditions could exist that could cause it.

Condensation below the matress is much better than "condensation" on top of the mattress...😬😳
Title: Re: moisture under bed
Post by: Travelin' Man (RIP) on February 20, 2017, 09:34:28 pm
What is the outside air temperature where the coach is?
Title: Re: moisture under bed
Post by: Old phart phred on February 21, 2017, 12:04:40 am
Moisture will migrate and condense on the weakest link, typically the windows. Is the engine losing water or a leaking furnace flue allowing extremely high humidity levels to rise to the top of the bed platform from the engine bay, more likely a undiscovered roof leak dripping on the bed.
Title: Re: moisture under bed
Post by: Old phart phred on February 21, 2017, 12:30:39 am
Another possibility for air beds only, pinhole leak in bottom of mattress. Moisture from the compressing process will accumulate at the bottom of the mattress.
Title: Re: moisture under bed
Post by: Travelin' Man (RIP) on February 22, 2017, 11:00:38 am
Another possibility for air beds only, pinhole leak in bottom of mattress.

Or a water bed Phred.  LOL
 
Never heard back from the OP on this subject after that one-and-only post.
Title: Re: moisture under bed
Post by: nitehawk on February 22, 2017, 11:53:34 am
Industrial strength Depends?? >:D
Title: Re: moisture under bed
Post by: Travelin' Man (RIP) on February 22, 2017, 12:09:25 pm
No sweat!!
Title: Re: moisture under bed
Post by: Texas Guy on February 22, 2017, 03:35:20 pm
Talk about getting SEASICK, oh man can you imagine

how it would feel to try to get a nap on a waterbed in

the back of a FT on the road. Scary !  Glad they are out

of style now.

Carter-
Title: Re: moisture under bed
Post by: cubesphere on February 22, 2017, 03:41:47 pm
Hello everyone,

You wouldn't by chance have a roof vent cracked open going down the road would you? I had a friend who left the vent open on a humid day going down the road and the back bedroom floor would get wet. Just a thought.
Title: Re: moisture under bed
Post by: Chuck & Jeannie on February 22, 2017, 05:29:54 pm
Dave's not here.