Rainier70 wrote:I went camping for several nights over the weekend of Apr 12th. My heater ran great except for some minor wind problems on one of the days. The wind was gusting at about 40+ mph, and it would blow out the flame if I had it on really low. I have a "high wind" cap on order so I hope it fixes that issue.
The main thing that I noticed was just how much cold was coming through the floor. It was pretty cold out at night, and I kept my heater going. It was about 65 deg in the camper when I got up and about in the teens or twenties outside. What I noticed was that where I had put my waders to drip over my shower pan the pool of water in it was frozen. A water bottle that I had left on the floor was partially frozen also. Both of those were frozen within 3 feet of the stove and when the temperature at 3 ft high was 65 deg. I know that I could put a fan on and stir the air a bit more, but it really shows me how much of a heat loss the uninsulated floor is.
I have since then started to insulate my floor. I am using 2in "pink" foam board. I am covering one side of the foam with the canvas-glue-paint coating that the foamie builds are using. I decided to try this method since I already had most of the supplies for it. I had to buy the Harbor Freight canvas at $15, but that was about it. The paints, glue, and etc are leftovers. If I had to buy everything, it would be getting close in cost to using the frp panels. It does take awhile though to glue and paint the canvas covers on.
Once the panels were dry, I put liquid nails on the back and then using screws and fender washers I put them up in between the ribs.
Edit: I used 2.5 inch screws. The fender washers hold the screw head out a bit, but there is just enough length to suck the foam panel up tight without going through the floor. I think my floor is 5/8ths.
So far I have put the four main panels in. I will be measuring the odd sized sections and doing them as the weather around here allows. Once all the panels are in I will be going around the edges etc with Great Stuff.
It will be interesting to see how well it holds up. But if there are problems then I can always just do plan B.... cover the bottom with the fiberglass reinforced panels.
lrrowe wrote:This is just a wild thought that just came to me. How about leaving an air space (maybe 1/4" or so) between the foam and the underside of the floor. Then if there was a weep hole there, maybe any moisture that did get in, has a way out. Again I have not taken the effort to consider all the pros and cons.
Rainier70 wrote:Mike, all I can really say is that I just don't know. We are so much drier that I haven't really worried about water staying in contact with the wood.
If I still lived on the coast......First I would do a good job of sealing the bottom wood and rails before I added any insulation. Then I would glue and screw my insulation up and seal the edges. I think it might be good for your piece of mind to at least leave one or more pieces not glued up. Then after a particularly wet trip, you could take that piece off and check conditions under it.
Best answer maybe to put a layer of frp or coroplast across the underside and seal it up.
Good luck and let us know how it works.
Mike S wrote:lrrowe wrote:This is just a wild thought that just came to me. How about leaving an air space (maybe 1/4" or so) between the foam and the underside of the floor. Then if there was a weep hole there, maybe any moisture that did get in, has a way out. Again I have not taken the effort to consider all the pros and cons.
That's an interesting idea Bob. Having extra air space that isn't sealed would defeat the purpose of insulation. However, if were easy to seal up, it might work. Your comment gave me and idea: create a 1 inch air space using 1x1 wood strips on the underside of the trailers floor. Then attach the foam to the strips. Then seal it up as well as possible. Is that worth the trouble? I don't know. I'll think about that for a bit.
AZ_Desert_Rat wrote:Great Job Cindy and thanks for the ideas and documentation of your tests
How has the under-floor foam been working for you so far ... I am considering doing something similar in my CT ??
Make sure to take some pics of that next trip
Rainier70 wrote:A preliminary verdict on the bottom insulation.
So far since putting my under frame insulation in I have travel well over 100 miles on gravel roads and about 300 miles on paved. I am seeing nothing but a little dust on the canvas covered insulation. I also have three small sections in the front of my ct that have mostly uncovered pink foam insulation. It shows a little dust and maybe a couple of little tiny rock dents. No real wear at all.
I private messaged BC Dave about his insulation also. He glued on his insulation with no covering. He hasn't traveled as much with it, but it is holding up fine and shows no damage.
Then I saw this post by Nobody. He has had uncovered insulation on the bottom of his camper since 2006, and had it on all kinds of roads.Nobody wrote:There probably as many answers to your question as there are builders on this forum. None are 'wrong' or incorrect. What's right for one person may not work as well for another.
I built my TD in 2006, using an HF 1800# trailer & a couple of profile drawings I expanded from quarter inch graph paper. I built my floor from ripped spruce 2x4's, 1x6 pine for side rails, & 1/2" CDX ply for the decking. After the 'floor' was completed I inverted it on a couple of sawhorses & 'painted' it with asphalt roofing compound. Contrary to conventional wisdom, the coating wasn't nearly as 'stinky' as expected, & the 'tackiness' only lasted as long as it took to dry (overnight). I then cut pieces of 1" styrofoam (Dow 'blueboard') to fit the recesses under the floor, installed them with PL Adhesive, & as an extra caution, I used small pieces of scrap wood as 'battens', 'nailed' to the floor frame with 18ga brads from my HF nailer/stapler. Almost 8yrs & 20K plus miles later (towed thru all kinds of terrain from freeway to National Forest/BLM back country roads/trails) the foam shows considerable stains/marks of travel, a few tiny 'gouges' probably from road debris, but NO deterioration or tendency to 'de-laminate' from the floor. In SE New Mexico in 2010 we encountered standing water in the streets of several towns, that in places almost 'floated' the TD. I've also driven through lots of heavy rain/T'Storms where I'm sure the tires & passing vehicles sprayed lots of water up under the TD. I've found no indication of residual moisture nor any evidence of rot in the wood portion of the floor, nor corrosion to the metal of the trailer chassis. As an aside, I live in central Arkansas where our average humidity is quite high & equipment not properly protected has ample opportunity to suffer ill effects from it...
Here's a few pix of my floor under construction
This how the underside looks this morning (not bad considering what it's been exposed to since 9/2006)
I think we have been over thinking and over engineering floor insulation. I don't regret covering my insulation with the canvas/paint coat, but after having seen how my uncovered insulation is holding up and how little "wear" others have experienced, I think it will be more than adequate for the long haul. I am wondering if the "cover the insulation" comes from RVs and trailer houses originally using fiberglass batts that needed protection from water etc?????
I will continue to check on mine on how it is doing, but I won't be canvasing over the small odd shaped pieces of exposed foam that are in the front. I will be doing some foam fill in spots that I haven't gotten to yet, but that is about it.
In short, if I was to do it again I would glue and screw the insulation on, or batten it, but I wouldn't worry about putting a cover over it. You could always do that later on if you wanted.
abqlloyd wrote:I'm using Tyvek house wrap under mine. It's what they use on high-end RV's and a small roll is cheap.
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