Community Forums

Gloomis · 03-19-2021, 05:50 AM

Hey guys. I tried doing a search on this topic but apparently I don't know what I'm doing and I know I've seen this topic before but couldn't find anything. I'm getting close to the point on my Midas where I'll be buying new foam insulation and putting the walls back together. I will also be installing new paneling on the inside as it's gutted at this time. Any recommendations for the adhesive? I remember reading that some of the propellants will eat the foam. Has anyone used the foam with the aluminum backing on it to avoid this issue and then used a product like Gorilla glue? Thank you.

Guy

ByeTheWay · 03-19-2021, 04:00 PM

Following this post

clifford j · 03-19-2021, 04:27 PM

My first thought is not what adhesive but what type of insulation product to use and is adhesive necessary. Are foam boards the best choice for walls and ceilings, is foam the best r factor where needed. Lots to consider

CLIFFORD

Gloomis · 03-19-2021, 04:29 PM

I'm putting it back as it was as far as the foam insulation. The adhesive is a must as it anchors the outside aluminum skin.

Guy

rte154 · 03-19-2021, 06:55 PM

I think weldwood contact cement would work very well on that application. It should work on either straight foam or foil backed. For the unbacked foam it would take 2 coats. Brush on first coat, let dry then put second coat on it and 1 coat on exterior wall. Let both dry completely then assemble. It should be a permanent bond. Weldwood can be bought in any hardware store or I have bought it in Walmart. Available in quarts or gallons. Very cheap but unbeatable for strength if properly applied.

RichardE · 03-19-2021, 07:09 PM

Seriously. Identify what foam you are going to use. There are many many different foams that differ in chemical structure. Once the foam is picked, an appropriate adhesive can be chosen. Pair the wrong adhesive with the foam and the solvent in the adhesive will dissolve the foam.

Be very careful using contact adhesive in large quantities in small confined spaces like an RV.

jjrbus · 03-19-2021, 10:07 PM

Stabond is the premium one. But few will use it once they see the price!

sam-3 · 03-20-2021, 02:15 AM

I used heavy duty liquid nails when i repaired my water damaged walls. It doesn't eat the foam. Some have used Locktite caulk.be very generous with your binding caulk. Dh used a flloor roller to make sure all the layers bonded.

KtownKajun · 03-20-2021, 05:11 AM

Find a local Spray foam contractor to come in and spray it. Make sure it’s prepped well as to not get all over the place. More foam and R value is not always better, you want a good seal. Remember your freezer has a “R” value of about r7. Check to see if the contractor has a low minimum job cost. As it can get pricey Use only closed cell. Another option if you can’t find a contractor to do it is DIY kit. Called “Froth packs” can be found online or at your local insulation suppliers. Read the instructions but They are pretty easy to use.

Seon · 03-20-2021, 07:18 AM

3m spray adhesive

Guppy · 03-20-2021, 07:35 AM

Use gorilla glue. It uses moisture to cure. Dampen the siding and the foam. Then clamp the foam in place. Have a few small 1/4" inch holes on the foam to let some of the glue out. The glue expands a bit and will fill all the small dips and gouges. You must clamp the foam and the outside to stop the exterior of the siding from bulging. The glue will stick to the interior wood as well leave a 1/4 gap at the top and bottom of the wood for the glue to expand. The wood and the foam need to be moist. This makes a very air tight and moisture proof seal on the wood,foam insulation and the siding. It will never delaminate over time and movement. Take your time and brace/clamp the exterior of the rv wall and all will be better then new.

arcaguy · 03-20-2021, 08:05 AM

I believe it is 3m that makes a foam adhesive, if not them. someone does I have a can of it around here somewhere. I would try a sample with some scrap material to make sure the adhesive will not dissolve the foam and that the bond is acceptable. I would also spray the adhesive on both materials and use a Formica roller (about $10.00 at your favorite big box home improvement store) to ensure a good bond. Just remember to make sure that the pieces are where you want the when they go together because it may be very hard to get them apart once they touch. You can use some dowels or small pieces of wood to keep the pieces apart until they are aligned. I would also search for Formica installation on the Internet, the process will be about the same. Good luck.

Gloomis · 03-23-2021, 10:40 AM

Thanks for the suggestions guys. I was at the building supply last weekend looking at some of the products they had. The employee that I was talking to suggested the 3m product. When I get to that point, I'll do some testing before going wide open into that portion of the project. I post on my Midas thread.

Guy

WrkItRalph · 03-23-2021, 09:00 PM

Hi Guy,

I’m in the middle of a project much like yours. I picked up Loctite 300 Foamboard Adhesive at Home Depot.

https://www.homedepot.com/p/Loctite-...1941/202020476