My Girlfriend is a real trooper during hunting season. She struggles during the cold weather, and cannot sit outside for long periods of time.
We decided to build her a "mobile deer hunting shack" for the upcoming deer season. We will drag the "shack" around with the Honda Pioneer side by side.
With sheet metal exterior construction, well insulated, several Lexan/Acrylic "flip up" windows, and a Mr. Buddy catalytic propane heater inside, it will be toasty warm & dry inside the 4' x 8' box.

I need some help from the brain trust here.
The trailer is now repaired, the "shack" wooden framework is completed and attached to the trailer. (it's similar to a "Morton Building" and it is a rudimentary post and beam style)
The sheet steel roofing is mostly installed on the wooden framework. (walls & roof)
I've got two triangle shaped pieces of metal roofing that still need to be "custom" cut using a cardboard template.
I also need to make and install the entry door.

I have a good supply of rigid Styrofoam board in several different thicknesses. (one inch and 1-3/4 inch thickness)
The plan is to seal all the residual openings/gaps from construction with insect resistant closed cell spray foam.
My GF is allergic to bee/wasp/hornet stings, so the "shack" really needs to be sealed up good from insect intrusion during the 10 months out of the year it will just be sitting outside.

Here is where I need help. I need an adhesive (preferably in a tube for a caulking gun) that will permanently bond the Styrofoam board to the sheet steel roofing material inside the "shack" on the walls.
The floor and ceiling is easy and shouldn't require adhesive. (mechanical attachment works for the Styrofoam on the floor & roof as there is wood available underneath the Styrofoam)
The trailer already has a 3/4" marine plywood floor, I was going to place a Styrofoam board on the floor, and cover the Styrofoam with 1/4" or 3/8" plywood/chip board.
The ceiling has exposed purlins inside, and the Styrofoam can be attached with screws and flat washers overhead.
For "blacking out" the interior, I was thinking about using a gardening/geo-textile material as it's black and low budget.

I won't waste Forum bandwidth with photos in this post, I have photos here so you can see what I am doing: https://sigforum.com/eve/forum...35/m/7230077564/p/10

I am out in the boondocks but I do have a Lowe's store nearby. We've used a lot of recycled materials in the "shack" construction, we aren't building a home.
The goal is $200 to $250 in total for the entire project.

Please help me select an affordable caulking gun applied adhesive that will permanently bond the Styrofoam board to the interior sheet metal roofing wall surfaces.
I am looking for a recommendation based on personal experience with a particular adhesive.

I don't have a specific brand/number recommendation, but I know they make a caulk-style adhesive specifically for bonding styrofoam.

Check your local building supply place.

I would guess that Lowes has the Gorilla Glue in stock, they do here, and they have a lot of products for different applications.

https://gorillatough.com/

For a caulk gun applied adhesive, I used Liquid Nails Foamboard adhesive to attach polystyrene to my train table years ago and it worked well to hold the board without damaging the insulation board for fifteen years until I finally disassembled it and repurposed parts of the table a couple of years ago. On the underside of the roof with the top and sides of the roof waterproofed so there's no direct exposure to rain, it should work well. This assumes the current formula is similar to what I used back then. Good luck!

https://www.ppgpaints.com/prod...onstruction-adhesive

I hate to sound like the geek, paranoid one, but I think I'd let anything you use air dry really well in a ventilated area to keep any noxious fumes from being in there. Especially if she's in there for a long period of time with everything closed up (on very cold days).

After wading through dozens of technical data sheets for a wide variety of caulking gun applied construction adhesives, VERY few of them are rated by the manufacturer for bonding Styrofoam to galvanized steel.
I will have to make a trip to the non big box building supply store and see what they recommend.
So far, I've only found one adhesive that's rated for bonding Styrofoam and galvanized steel, and it seriously fails on affordability. $14 for a single ten ounce tube.

At least one window will always be open when the "shack" is occupied.
Otherwise, fiddling around, opening the window, sticking a rifle or handgun barrel out the window will likely result in a missed opportunity for harvesting a deer.

She's been using a fabric pop-up blind for years now, the Mr. Buddy catalytic heater has enough BTU output to keep her warm with multiple windows open in the drafty pop-up blinds.
Most of the construction adhesives are rated as Low emission VOC.

When the "shack" is completed, it will be at the hunting location for at least six weeks before being actually occupied for hunting purposes.

If I need an adhesive to bond forever I go to 3M 5200.
https://www.3m.com/3M/en_US/p/d/b40066983/

quote:

Originally posted by armored:
If I need an adhesive to bond forever I go to 3M 5200.
https://www.3m.com/3M/en_US/p/d/b40066983/

If op thought 15.00 fails on affordability, then 5200 is way out of the picture.

I know it’s not what you asked for but is spray foam insulation an option?

Looking at your pictures, cut the styrofoam to fit inside the 4x4 uprights and use furring strips to hold the styrofoam in place against the metal. No need for adhesive. Nail the strips to the 4x4s along the edge of the foam panels.

5200 by 3M. It’ll work but it’s pricy.

What are you going to do when the deer smells the propane?

@400m, I already have a adequate supply of Styrofoam board for the job. Paying a spray foam contractor or buying a DIY kit for spray foaming it myself will add significant cost to the build.

@trapper189, Thank You for pointing me to the mechanical attachment direction. I think I have figured out a method of holding the Styrofoam board against the steel roofing panels using tightly stretched wires strung between the vertical wooden posts.

@41, Deer smelling the propane combustion byproducts hasn't been a problem in the past using the fabric pop-up blinds. I don't expect that to change.

So far, all the materials for the "shack" except for the nuts, bolts, construction screws, structural lag bolts, and rubber gasketed roofing screws has been repurposed, recycled, or used.
For the old trailer, I did have to purchase two new wheel bearings and grease seals.
There is a Dollar store in town that has rattle can spray paint for $1 per can. That will work for the "shack" exterior "camo" paint job.

OP aboard ship where the walls are steel, we used 5200 to glue a big tack to the wall all over spaced out about every foot, then smacked the insulation on, and bent over the end of the “tack”.

So not so much as gluing the insulation but the attachment (the big tack)

You may be able to do something like that and reduce the cost of the glue. I don’t know where the shipyard got the fastener, but it was a 2x2” sheet metal square with a long thin aluminum nail thru it-prolly 3” long, then you bend the part that stick out of the insulation

^^^ Mike, that's great idea! See it all over ships.

Consider buying her a heated jacket, Milwaukee sells them and they run on their 12volt batteries. You can get one at Home Depot.

Heated jacket

Mechanical attachment is where my mind went. Foam board is stupid light so strength of bond isn’t all that big a problem.

There are adhesives specifically for this purpose. Example 3M78. But you aren't going to find that at Lowes. What you need is a general purpose construction adhesive and that they have. Tiny amount per panel will be just fine.
There is no need for 5200 its designed for a completely different purpose none of which matter to you (allow use below the waterline, seals, flexible, resists weathering, salt water, etc. etc. I use the stuff all the time there is no need for it here).