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Why doesn't anyone use this to seal their floors?...

PostPosted: Thu Dec 06, 2007 9:12 pm
by lvrdrm
Hello, new guy with his first post. Getting ready to start build on a 10' tiny travel trailer. Been reading the various methods to seal the underside of your trailers and was wondering why nobody uses black Darco underbelly material that is used on RV's/Motorhomes. It is a protective layer of woven polypropylene that completely wraps the underside of your completed frame to create a weather resistant underbelly. This material is also rodent proof, puncture & tear resistant for years. Just seems better than messing with all that tar stuff from the can??? Just received 14 feet from Fleetwood and seems to be of good quality. Will post pic when I figure out how to do it.
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PostPosted: Thu Dec 06, 2007 9:35 pm
by Weerider
Welcome lvrdrm glad to have you aboard. :D

I am not familiar with the product you mention but I would imagine that the black goop we are all using is so popular because you can get it at any building supply, it's cheap, it's effective, it's easy to apply and if you use a cheap throwaway roller, it isn't even messy.

Keep working at the picture thing... we all love pictures! :D

Howard 8)

Re: Why doesn't anyone use this to seal their floors?...

PostPosted: Thu Dec 06, 2007 9:43 pm
by toypusher
lvrdrm wrote:...................... Will post pic when I figure out how to do it.



Try HERE

lets see

PostPosted: Thu Dec 06, 2007 9:51 pm
by lvrdrm
I know the picture doesn't say much but wanted to show as much detail as I could. Besides the thing is 8' wide! Just got it in this afternoon.

Image

Please note: the pic below is not from my actual build. Borrowed it from the net.

Image

PostPosted: Thu Dec 06, 2007 10:05 pm
by Ralf
I went to a local RV dealer to see what a torsion axel looks like. When I crawled under an RV to check out the axel I noticed that fabric covering the bottom. It did not look very sturdy but I will take your word for it. I guess they wouldn't use it if it didn't work. I did buy a torsion axel and used the black goop. It took my 2 boys and me just a few minutes to slap it on. I also bought a tube of goop for the calking gun and hit all the seams. I used my finger in rubber glove to smooth the bead and force into the seams and corners.

PostPosted: Thu Dec 06, 2007 10:09 pm
by Ken A Hood
And the million dollar question: how much?

The black goo is available everywhere and relatively cheap........

PostPosted: Thu Dec 06, 2007 10:29 pm
by lvrdrm
Ken A Hood wrote:And the million dollar question: how much?

The black goo is available everywhere and relatively cheap........


I paid $60 bucks for it shipped but I ordered more than I needed. I know also alot more than buying me a $10 dollar gallon of goo. Since you all use smaller bases you could probably get some for half the price.

I just did my own "quality-test" on this stuff and this is what I have so far.

1. The knife pierced pretty easily.
2. It will not continue to tear or "unseam" by pulling on it. Looks tough.
3. One side of it looks very similar to a regular blue tarp you can buy anywhere.
4. The other side seems to be smooth, sort of like it is two ply or has been heat pressed.
5. Since I ordered more than I need, I already took a piece off and will do a water test, over a 5 gallon bucket, for awhile. We'll see how it holds.

Image

PostPosted: Thu Dec 06, 2007 10:40 pm
by Steve_Cox
Hello Newguy with big plastic sheet to wrap his floor.

I can tell ya why I don't like that stuff. I've seen a few travel trailers with a soft , delaminated plywood floors, and they have all been wrapped in a plastic sheet. One had a leaky shower and the plastic didn't let the water drain out. one had a leaky door seal, and the plastic didn't let the water drain out and the last had a leaky water tank under the bed and the floor fell apart, good thing it had the plastic there to catch the pieces :lol: :lol:

I like my plastic roofing tar coating since it became part of the floor and not just a place to gather water that has made it way through or around the floor. I also coated all my plywood with epoxy to make it waterproof and put foam board insulation under the trailer floor.

Trailers are a lot like boats in two regards. You need to keep the water out and if it gets in you need to get the water out. Try getting water outta that black plastic bag...... 8)

PostPosted: Thu Dec 06, 2007 10:42 pm
by lvrdrm
Ralf wrote:When I crawled under an RV to check out the axel I noticed that fabric covering the bottom. It did not look very sturdy but I will take your word for it. I guess they wouldn't use it if it didn't work.


As far as sturdy, It doesn't seem to offer any kind of structural support. I too have seen them under RV's and they seem to kind of just hang there. I wonder if the manufactures just throws them on there or if they really apply them tight. Maybe they sag after awhile? The one I have on hand does not stretch whatsoever? Will post results as I come across them.

PostPosted: Thu Dec 06, 2007 10:57 pm
by Micro469
Steve_Cox wrote:Hello Newguy with big plastic sheet to wrap his floor.

I can tell ya why I don't like that stuff. I've seen a few travel trailers with a soft , delaminated plywood floors, and they have all been wrapped in a plastic sheet. One had a leaky shower and the plastic didn't let the water drain out. one had a leaky door seal, and the plastic didn't let the water drain out and the last had a leaky water tank under the bed and the floor fell apart, good thing it had the plastic there to catch the pieces :lol: :lol:

I like my plastic roofing tar coating since it became part of the floor and not just a place to gather water that has made it way through or around the floor. I also coated all my plywood with epoxy to make it waterproof and put foam board insulation under the trailer floor.

Trailers are a lot like boats in two regards. You need to keep the water out and if it gets in you need to get the water out. Try getting water outta that black plastic bag...... 8)


BOY!!! did I learn this the hard way. When I built my shed/workshop about 20 years ago (has it really been that long??) the floor was framed with 2x10's so it was off the ground.I covered them with sheet plastic (kind of like a vapour barrier) before I nailed the plywood floor down. Of course, after time the door leaked and water got inside. Leaked through the floor and was stopped by the plastic. You can guess what happened. Two years ago I had to replace 3/4 of the floor because it rotted out. Needless to say I removed as much plastic as I could get at, because when I ripped up the floor there was about 1.5 inches of water on it. Had to replace the door frame and part of the wall around it.
The best advice I can give... if water can get in, make sure it can get out.

:)

PostPosted: Thu Dec 06, 2007 11:08 pm
by lvrdrm
Steve,

I guess the stuff performed as it was intended. :lol: But how will sealing the wood with goo be any different? Is it because its permeable so if water gets in, it will get right out? I think if the water leak resides from the inside out, one has another issue to deal with. I will not be installing shower or extensive plumbing for that matter. Just trying to find the best protection for the external elements.

PostPosted: Thu Dec 06, 2007 11:08 pm
by madjack
...about the only way I would use such, would be to goop it up with the tar first and then lay that stuff into the wet tar...be VER WARY of anything that forms a belly pan because as stated, it can and will catch and hold water...the bottom of the floor is a place that too many obsess over sealing...it doesn't rain from the ground up and the only time it will get wet is when towing inna rain...asphalt emulsion, roofing tar, a good grade of paint, urethane, epoxy or almost anything will suffice for sealing the floor..........
madjack 8)

PostPosted: Thu Dec 06, 2007 11:20 pm
by lvrdrm
good call MJ. Before I put this on, I want to weigh out my options and unfortunately at a 60 dollar expense one. I have other uses for it if I don't end up using it. My main concern is for belly's to form up under there. :thinking:

PostPosted: Thu Dec 06, 2007 11:26 pm
by Dale M.
Looks like the woven polypropylene cloth tarps are made from....

Dale

PostPosted: Sat Dec 08, 2007 5:32 pm
by Jiminsav
I used Thompson's water seal..like Jack sez, it don't rain up. 8)