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Old 11-28-2012, 12:18 PM   #1
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Join Date: Nov 2012
Location: Utah
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Okay so we all know I am utterly clueless!
I am going to pull out the back wall as soon as I get back from Disneyland and have heard or read a few people conversing about membranes and their importance and how not to cut it etc.
Terrified of pulling down the bunks and the wall only to find major probs with the floor- I am a bit if a fraidy cat!
So what is a membrane?
I have owned a travel trailer in the past and it had a metal liner/subfloor under the floor of plywood and the metal was rusted almost thru where the bathroom was so we tore it out re welded a piece to fit and redid the bathroom with an OLD portapotty ( I am sometimes frugal, usually not if I want it I save for it because no one else is going to get it for me but my ex was an on the spotter and did what the moment called for- in this case having a loo.)
back to it I thought all travel trailers had metal on the bottom to keep moisture from rebounding back up and rotting your floor, keep rocks and racoons from getting in. Thanks for your help hope I do not come off as too dumb for this project!

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Old 11-28-2012, 07:28 PM   #2
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Hi Vintagecaryn,

Your unique camper is made different most likely from our Sunlines in some ways. Part of this is the age as methods have changed over the year. And then there is a lot of simialr methods.

Some of the older Sunlines had sheet metal on the bottoms as well. I do not know exactly what was above the sheet metal. Wood floor or a membrane.

On the more newer campers we have a waterproof membrane. It is heavy woven plastic sheeting. It is light, cheaper than metal and will not let water through in either direction as long as there is no holes in it.

See here under my camper. That black bottom surface is whet is called Darco waterproof membrane.

Here I am measuring how thick it is. They consider this 12 to 13 mils thick. It is like a heavy tarp in thickness.

Here is some of it on the ground where I can cutting it to install on my slide floor

It can be mended with a special tape called Flex Mend or under belly repair tape. They sell this at moble home supply places. It sticks on and is permanent.

If you are handy with wood working, there is nothing in your camper that cannot be fixed in the frame, walls, roof etc.

Good luck and hope this helps


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Old 11-29-2012, 12:37 AM   #3
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Thank You John B. it helps a lot. I am thinking I shall put this under everything if I pull the whole thing apart. If I do not go that far- all the way to the frame -then I shall try to put it down where I can! It seems to be a handy item and somewhat like the moisture barrier I recall using when I roofed 20 odd years ago. I can not wait to get started. If I never know what this really I think I still like it, now to name her.
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