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
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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