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76Scoutman's avatar
76Scoutman
Explorer
Sep 24, 2013

Adhesive for attaching Filon to roof

Howdy all. I have been working over the past few months on repairing my pop up truck camper after the roof had an RUD (Rapid Unscheduled Dissassembly). I've been reading up on all my options for getting the roof back on and have located a place in town that stocks Filon which will save me on $1-200 worth of shipping costs. The question that's making me cross-eyed at the moment is what adhesive to use to glue the stuff down with.

My TC is made with wooden ribs, lauan ceiling, and Styrofoam insulation that is skinned with Filon. Actually the original roof was probably closer to flex roof which is just a textured version of Filon. Either way it's a continuous sheet of FRP (fiberglass reinforced plastic). The front edge is curved down so the Filon has to conform to that contour. The side walls of the roof section are a laminated Filon/Plywood/etc that are attached to the wooden roof ribs.

Adhesion surface would be approx 95% Styrofoam and 5% wood

Other roofing options such as Rubber/EPDM, PVC, and TPO roofs have been eliminated due to the fact that they all need to be stuck down to a sheet of lauan or similar hard sheet roof which I'm not adding. Aluminum has been eliminated also so those options aren't even on my table.


Adhesives----
-I see some say contact cement which to me is a general term. Lowes has DAP Contact Adhesive but reading the fine print says not to use it with Styrofoam. The RV dealer I'm getting the Filon through said they use contact adhesive but I haven't asked what type yet.

-Some say Stabond E-183 which is actually the recommended glue for Filon but I'm not sure if it will eat the foam that it will be glued to. At $174 for the gallon + $30 hazmat fee + shipping costs via special carrier--- this is not a gamble I want to take. I believe it is applied with a spray gun and is extremely flammable.

-I just stumbled on a Titebond product that I can get on Home Depot's site. It's http://www.homedepot.com/p/Titebond-3-5-gal-Greenchoice-Advanced-Polymer-Adhesive-4319/203506897#.UkHs_MakpdwTitebond Advanced Polymer Panel Adhesive. I just spoke with their tech support and it sounds like it would work pretty well. It costs more than the Filon I'll be getting but if it works then it'll be worth it. It trowels onto the Filon and is moisture activated so it sounds much easier to work with.

Anyway, I'm looking for some experience from the RV forum on the best product to use. I'll see if I can get some picts posted soon and this will give me a place to add anything else I may find....
  • Yea, I have NO desire to lay fiberglass by hand. Been there, done that, don't wanna do it again.

    I'll do some more looking into the silkaflex stuff. I still wonder on these 'caulk' type tubes... do I just buy a bunch of them and squeeze them out and spread with a trowel or what? Is it intended to be used on the ribs or for everything? I would have thought I would be looking for a pour-able product that I can spread with a brush or roller. The threads I found were using it on the ribs only.

    I still haven't ruled out the Titebond product. I was reading a thread here on RV.net the other night and saw someone else using it too.

    So my latest is that I went and visited another local RV shop. They have the Filon for $8.50 per linear foot off of an 8' wide roll. The stuff is flexible enough to easily do the front bend radius that I have. The last question is adhesive.

    I talked to one of the head tech guys there and we talked about some other alternatives. One of the other approaches would be going with a 1/8" luan glued to the ribs and foam, screwed to the ribs with countersunk screws, and then a pvc or epdm roof applied on top of that. The 1/8" luan which I (didn't know it came that thin) is one of the parts I'm still nervous about. Cost wise, this approach would be more because I would have the cost of the first glue, filon, pvc glue, and pvc material which all add up to way more than my original plan.
  • polyester resin used for fiberglassing will melt styrofoam. Anything epoxy based will adhere well.

    So if you use luan on top of the foam, whats going on the luan? Rubber?

    what I would do is head to home depot and grab a qt of the floor adhesive. Test it on some styrofoam and if it doesnt melt it, I would go get a gallon of it and trowel the adhesive on just as a floor job and then screw the luan to the frame. You really want the structual integrity of the whole roof to keep it from all falling apart in transit.
  • So I just ordered a 3.5 gallon container of Titebond Advanced Polymer Adhesive from HomeDepot online.

    http://www.homedepot.com/p/Titebond-3-5-gal-Greenchoice-Advanced-Polymer-Adhesive-4319/203506897#.Ul1lbsakpdx


    ~$135, shipped
    -no hazmat or special shipping to deal with
    -no special application tools other than a trowel
    -it works on non-porous and porous substrates
    -adheres to just about everything including Styrofoam
    -easy to clean up
    -mold/mildew resistant
    -moisture cures
    -exterior and interior uses

    So far this was my best option. I know there are many other alternatives and some of those are approved for use on Filon but most of those I felt were not right for me and my application.