Thread Tools Search this Thread Display Modes
Old 02-08-2015, 08:28 PM   #57
3 Rivet Member
gsmithii's Avatar
2013 30' Flying Cloud
Virginia Beach , Virginia
Join Date: Nov 2009
Posts: 148
Step by step

We spent last week camping in Williamsburg where the lowest overnight temperature was about 15 degrees. Temperatures in the twenties were pretty common and we now have a fair test of our Reflectix/1/2 inch neoprene/Reflectix sandwich under the mattress.

The moisture under the mattress has been dramatically reduced from really wet to - just slightly damp when we checked it in the morning. The top surface of the sandwich was significantly warmer than the bed platform which suggests that the insulating properties of the sandwich were pretty good.

Next step - winterize the trailer and fly to a tropical destination.

Oh! For this problem I plan to ponder the mysteries of the universe until we prepare for next winter's camping. Choices are to do nothing and see what happens or to add another layer to the sandwich. HyperVent, anyone?

Speed is Life . . . guidance is optional . . .
The Traveling Circus: 2013 Flying Cloud 30A; 2006 Chevy Duramax Crew/LWB
Air #42313 TAC VA-7 WBCCI #1290
gsmithii is offline   Reply With Quote
Old 02-09-2015, 04:39 PM   #58
Rivet Master
chaseav's Avatar
2015 25' FB International
Join Date: Nov 2014
Posts: 534
How about some foam core insulation? That's probably not the right term but the 4x8 sheet stuff they sell at a hardware store. Shiny side down. It's light, it's rigid and that's what it's designed to do.

chaseav is offline   Reply With Quote
Old 02-09-2015, 09:07 PM   #59
Rivet Master
cwf's Avatar
1999 34' Excella
Currently Looking...
Hillsboro , Texas
Join Date: Feb 2013
Posts: 6,095
Images: 2
Originally Posted by chaseav View Post
How about some foam core insulation? That's probably not the right term but the 4x8 sheet stuff they sell at a hardware store. Shiny side down. It's light, it's rigid and that's what it's designed to do.
On underside of bed plywood perhaps to stop cold from getting to the bed to begin with.

I wonder, was mattress warm underneath?
Peace and Blessings..
WBCCI# 30676
cwf is offline   Reply With Quote
Old 02-10-2015, 04:00 PM   #60
Rivet Master
chaseav's Avatar
2015 25' FB International
Join Date: Nov 2014
Posts: 534
I'm thinking above the wood so that the heat in the mattress and therefore the moisture, never transfers to the wood which would then retain water.
chaseav is offline   Reply With Quote
Old 02-10-2015, 04:20 PM   #61
Rivet Master
TinTin's Avatar
2009 23' FB Flying Cloud
Canmore , Alberta
Join Date: Nov 2013
Posts: 1,762
Images: 6
I think you could insulate under the bed (i.e. beneath the wood) if you put a vapour barrier above the wood to keep humidity away from the wood. Insulating beneath the wood without an upper vapour barrier might cause more problems than it solves.
Bob and Nancy
Cheer Up, Slow Down, Chill Out!
TinTin is offline   Reply With Quote
Old 02-10-2015, 04:24 PM   #62
Figment of My Imagination
Protagonist's Avatar
2012 Interstate Coach
From All Over , More Than Anywhere Else
Join Date: Dec 2011
Posts: 10,624
Dumb question, but why not coat the plywood with Thompson's Water Seal to keep it from absorbing moisture? That way the plywood itself becomes a vapor barrier.
WBCCI #1105

My Google-Fu is strong today.
Protagonist is offline   Reply With Quote
Old 02-10-2015, 04:47 PM   #63
4 Rivet Member
Cannonball's Avatar
2014 22' FB Sport
San Antonio , Texas
Join Date: Jan 2014
Posts: 490
Images: 1
I asked that same question in a different thread on this subject. One reply was that they would be concerned about using a chemical product like that in an enclosed space, and that close to your person. Made sense to me. Whenever I have used Thomson's on a deck, it was pretty stinky. I am going with your Reflectix plan. Have it down, and will get to try it out this coming weekend.
Cannonball is offline   Reply With Quote
Old 02-10-2015, 04:52 PM   #64
Rivet Master
dkottum's Avatar
2012 25' Flying Cloud
Battle Lake , Minnesota
Join Date: Jun 2009
Posts: 7,716
I have used Thompsons Water Seal, but never would indoors.
Doug and Cheryl
2012 FC RB, Michelin 16, ProPride 1400
2016 Ram 1500 Laramie Crew Cab 4X4 Ecodiesel 3.92 axles

The Truth is More Important Than the Facts
dkottum is offline   Reply With Quote
Old 02-10-2015, 06:46 PM   #65
Rivet Master
chaseav's Avatar
2015 25' FB International
Join Date: Nov 2014
Posts: 534
Nooooo... that's outdoor use only and even then it needs a stiff breeze during application. Been using it for years on concrete and decks. It would only repel the moisture and cause it to build up on the outside of the wood which doesn't solve the problem. I'd rather replace the wood every few years. Foam core is the solution I think. Probably on the door, semi-permanent for winter use.
chaseav is offline   Reply With Quote
Old 02-10-2015, 10:41 PM   #66
Rivet Master
TG Twinkie's Avatar
1974 Argosy 26
Morrill , Nebraska
Join Date: Nov 2009
Posts: 5,277
Images: 2
Blog Entries: 5
The moisture under the mattress is not from the outside unless you have a leak.
Condensation from the inside moisture is the cause. The plywood is cold and the moisture condenses on it just like when the windows in your TV fog up.
Adding to the problem. The moisture is absorbed into the mattress. Plus the mattress acts as an insulator from the warm space.
Heating the space below the plywood is one answer. It does not have to be as warm as the cabin temp. Just enough to where the dew point is not reached.
Another solution might be to raise the mattress off of the plywood. What comes to mind is the teak slats used in shower stalls to keep your feet off of the floor.
The idea is; they are slats that would allow air to flow under the matters. Any material that will not absorb moisture and create a sort of grate under the mattress may work. Something that would not rust.
Just thinking out loud.

Sent from my iPod touch using Airstream Forums
Knowledge: "A gift to be shared. A treasure to receive."
TG Twinkie is online now   Reply With Quote
Old 02-11-2015, 03:58 AM   #67
Rivet Master
Florida 55's Avatar

2008 27' Safari FB SE
Pfafftown , North Carolina
Join Date: Jul 2010
Posts: 869
Images: 42
Blog Entries: 4
There is a product specifically designed to eliminate the problem of moisture condensation under cushions. It is a spacer fabric that provides both lift and air circulation. Spacer fabrics are used for marine, automotive, and other applications. There are several sources for spacer fabrics you can find on the Internet. Here is a link to one resource;

I have no personal experience with the vendor listed above so I cannot attest to the quality or suitability of the product. I have direct access to a US textile mill producing these fabrics but I am unable to obtain product for resale as my client will not sell directly to the public.

My knowledge of these products comes from years of work in the textile industry. If you have air cooled seats in your automobile or truck there is likely a spacer fabric directly under the leather or vinyl seat cover. Air does not circulate easily through the dense foam used in vehicle seats. The layer of spacer fabric over foam allows cool air to circulate from an air blower to the holes in your seat cover. The foam under the spacer compresses to provide cushioning while the spacer fabric lifts the seat cover above the foam allowing air to move.

Some high tech running shoes also employ spacer fabrics. Athletic shoes have both moisture management and compression requirements. Spacers are also employed instead of foam in some high end brassiere molded cups. No further comments but you ladies understand the issues.

Spacer fabrics can be purchased in various thicknesses. The amount of compression the fabric allows can be varied as can the density of the fabric. Some spacers actually employ moisture wicking fibers.

An inch to two inch thick roll of spacer fabric, with a fairly open construction and limited compression should be perfect for air circulation under an RV mattress, using a synthetic fiber such as polyester. The right spacer fabric will hold your mattress above the plywood, allow air to circulate under the mattress, and prevent condensation from being trapped.

I suggest doing an Internet search for suppliers, do some reading, and then call suppliers to talk about the application. Some of them may be willing to send you a small sample before you make a purchase.

There are only a few textile mills remaining in the US capable of producing these specialized fabrics. While I know what it costs to produce the fabric, I don't know the markup structure between the mill, the retailer, and the consumer. I'm guessing a spacer with enough loft and sized for a queen mattress would cost a consumer between $60 and $100, but this is pure speculation.

If anyone has questions, post on this thread or send me a PM.

Sent from my iPad using Airstream Forums
Airstream - 2008 Safari 27FB SE (Sweet Pea)
TV - 2011 Ford F250 Lariat, 6.7 Diesel, 4X4 (Brutus)
TAC FL-55 | WBCCI 3823 - Unit 12 | AIR 48265
Florida 55 is offline   Reply With Quote
Old 02-13-2015, 03:40 PM   #68
Rivet Slave
Rocinante's Avatar

2014 27' FB International
Green Cove Springs , Florida
Join Date: Dec 2013
Posts: 4,176
Blog Entries: 49
Condensation under bed??

Camped this week with our Reflectix and Hypervent sandwich. External temps were in the low 40's at night with an internal temp of 63. Not a particularly tough test, but no moisture formed on the Reflectix, though we did get some condensation on the windows. A good start.
Rocinante is our 2014 International Signature 27FB
(Named for John Steinbeck's camper from "Travels With Charley")

Rocinante is offline   Reply With Quote
Old 02-13-2015, 03:47 PM   #69
Rivet Master
r carl's Avatar
Vintage Kin Owner
Lin , Ne
Join Date: Dec 2009
Posts: 2,131
Originally Posted by Protagonist View Post
Dumb question, but why not coat the plywood with Thompson's Water Seal to keep it from absorbing moisture? That way the plywood itself becomes a vapor barrier.
How about linseed oil, wood oil, or varnish?
The higher your expectations the fewer your options.
r carl is offline   Reply With Quote
Old 02-14-2015, 02:54 AM   #70
Rivet Master
switz's Avatar

2014 31' Classic
2015 23' International
2013 25' FB International
Apache Junction , Arizona
Join Date: Sep 2012
Posts: 5,063
Images: 8
Since the Classic solid Hickory cabinets are sealed with a clear finish, I would think the same finished applied to the plywood might help and be safe.

WBCCI Life Member 5123, AIR 70341, 4CU, WD9EMC

TV - 2012 Dodge 2500 4x4 Cummins HO, automatic, Centramatics, Kelderman level ride airbag suspension, bed shell

2014 31' Classic model 30 twin beds, 50 amp service, 900 watt solar system, Centramatics, Dill TPMS, disc brakes, 16" tires & wheels
switz is offline   Reply With Quote

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Flying Cloud 25 B (rear bed) dkottum Buyer Guidelines 33 12-18-2014 12:51 PM
Switching the dbl bed & gaucho in a 24? Hittenstiehl General Interior Topics 15 01-30-2014 08:52 AM
Our First Trip - - But Condensation? redwoodguy On The Road... 32 01-09-2012 09:51 PM
Need Ideas for Bed Rails bike_addict General Interior Topics 4 11-18-2011 11:24 AM
Bed Mattress csorba General Interior Topics 1 09-06-2011 11:34 AM

Featured Campgrounds

Reviews provided by

Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -6. The time now is 06:32 AM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.

Airstream is a registered trademark of Airstream Inc. All rights reserved. Airstream trademark used under license to Social Knowledge LLC.