Adhesive for insulation foam board
I am redoing a couple sections of the roof on my Fifth wheel. I removed the membrane of the whole roof. Then I removed the 1/4"plywood and the 2.5" insulation foam from the sections I am replacing,...
Forum Discussion
While I have done the foam board roofing, when I have been in a bonding unknown situation what is the right product, I call the manufactures of the adhesives and ask for tech service. It is a hit or miss on who you get, and you may need to do a few companies, but here are a few to try.
Tell them the 3 substrates you want to bond to. Bare virgin wood and wood with old glue on ceiling board are two very different surfaces. Make sure you tell them, as one is porous and the other sealed shut from the old glue and the foam board is in the middle. It may be that you need two different adhesives pending the new plywood or the old ceiling board.
Loctite Corp, they are into a lot of adhesives
https://www.loctiteproducts.com/en.html
3M adhesives. 3M is into a lot of adhesives across many different industries.
https://www.3m.com/3M/en_US/p/c/adhesives/
Sika adhesives
https://usa.sika.com/
They are just a few of the bigger ones. Also make sure you let them know the application of the joint. This is more then just being able to bond foam board to wood. The roof flexes as the whole camper rolls down the road. The adhesive needs to not shear off in the event of a twisting action of the camper. As the roof load increases if you are in a winter/snow situation, the roof will compress and go below freezing. They make adhesives to deal with a lot of conditions, but the tech on the phone needs to know the application and may have very little knowledge of what stresses an RV can create. So you have to help ask good questions to hopefully get back good answers.
I do agree with you on wanting to try to get more close to total coverage on the adhesive. The bond ideally is working on 100% of the surface area to make it the most strong. Beads of glue works OK if you are just holding a panel to a wall. In this case, the foam board is structural in the ceiling/roof.
Also ask about compression to make the bond. Since the roof is still on the camper, it is going to be harder to create a 100% clamp like at the RV factory to clamp the sheets while the glue cures. The clamp you can create or not, need may change what adhesive is used.
Let us know how to make out.
Hope this helps
John
Tell them the 3 substrates you want to bond to. Bare virgin wood and wood with old glue on ceiling board are two very different surfaces. Make sure you tell them, as one is porous and the other sealed shut from the old glue and the foam board is in the middle. It may be that you need two different adhesives pending the new plywood or the old ceiling board.
Loctite Corp, they are into a lot of adhesives
https://www.loctiteproducts.com/en.html
3M adhesives. 3M is into a lot of adhesives across many different industries.
https://www.3m.com/3M/en_US/p/c/adhesives/
Sika adhesives
https://usa.sika.com/
They are just a few of the bigger ones. Also make sure you let them know the application of the joint. This is more then just being able to bond foam board to wood. The roof flexes as the whole camper rolls down the road. The adhesive needs to not shear off in the event of a twisting action of the camper. As the roof load increases if you are in a winter/snow situation, the roof will compress and go below freezing. They make adhesives to deal with a lot of conditions, but the tech on the phone needs to know the application and may have very little knowledge of what stresses an RV can create. So you have to help ask good questions to hopefully get back good answers.
I do agree with you on wanting to try to get more close to total coverage on the adhesive. The bond ideally is working on 100% of the surface area to make it the most strong. Beads of glue works OK if you are just holding a panel to a wall. In this case, the foam board is structural in the ceiling/roof.
Also ask about compression to make the bond. Since the roof is still on the camper, it is going to be harder to create a 100% clamp like at the RV factory to clamp the sheets while the glue cures. The clamp you can create or not, need may change what adhesive is used.
Let us know how to make out.
Hope this helps
John
