leaky roof & root questions

[wgonfan]

I'm sure this has been visited, but the search doesn't seem to return any results.  

   Last year I bought a 1988 coleman chesapeak with AC.  I tested the roof for rot & all seemed solid.  On one outing during the summer I noticed that some of the condesation from the AC was dripping out from around the AC inside the camper. I figured this was a common problem, so I just unleveled my PU a bit so that the water would run off at a faster rate.  While preparing for our 1st trip since I last stored the pop up, I noticed alot of water inside the camper.  With further inspection i found that the water had been getting in from the AC & lots had been soaked up by the roof.  The roof for the most part is as solid as can be. There are some spots near the AC that are soft.  I pulled the cover off the inside part of the AC & inspected the seal & the roof around that area.  I noticed that the roof seems to be two really thin (1/8") pieces of plywood with some sort of foam in between them.  In boating we use a product called "git-rot" to help stop rot & streanthen the all ready rotted spots.  I don't think this product would work with this sandwiched board.    

What do you guys suggest I do to sure up the already rotted placed & to help stop further rot.   Again, the roof is extremly solid except for the places right aroudn the AC  which are still pretty strong - the AC doesn't bounce & the roof has very little give when pushed on.

   I tried to pull the outside cover of the AC off so I could inspect the seal, but I couldn't get the cover off. is there a trick to this?

Thanks,
  TC

[Old Goat]

Here's what I would do with your roof problem.. Remove the AC unit and then determine how far the soft spots in the top extend out from the edges of the AC opening. Using a piece of 1/4" or 3/8" AC [good one side] plywood measure and cut out a piece that will cover soft spots and over lap them by 2 or 3 inches. Example; 3 ft x4 ft. or whatever..Cut radius on the corners of the piece and round the top edges of the good side.{ 1/8 to 3/16"}... Measure and cut the hole for the AC. This piece will be for the top side.. For the under side, using 1x4  lumber make up a frame that will be 2" longer and 2" wider than the top plywood panel.. Corners of this can be mitered  or butted and edges rounded  1/4 or 3/8"  radius with a router. Position this frame on the under side of the roof so that the edges will extend out 1" from the edges of the top piece... It can be held in place by couple of temporary short screws until top panel is installed..This makes a good foundation for the edge fastenings of the top panel...Layout,drill and counter sink the edge holes for top panel.. These should be 3/4 to 1" from the outer edges and 3 to 4" apart.. Use #8 flat head coarse thread wood screws, length to be determined... Give under side of panel a coat or two of sealer or urethane varnish before installing.. I prefer the urethane... Also cover the under side of panel with a good grade caulking before installing. This will eliminate any air space between panel and roof where condensation can form....Caulking will cure and bond panel to roof making it much stronger.Clamp edges of panel around AC opening until caulking drys. I don't think fastenings will be needed here  as weight of AC will keep joint tight... After filling the screw holes, panel can then be sealed with epoxy and painted. Make sure edges of panel are filled and well sealed... Seal all edges of AC opening to prevent moisture from seeping in and causing further rotting..

Git Rot is a great product but it is intended for cosmetic use only. It is only as strong as the wood it is bonded to which is usually soft from decay.....

If you have any further questions, let me know and keep me posted on your progress...Good Luck....