Attach foam board to a concrete slab?

[M8rtin]

I want it to stay put without creating future headaches, adhesive seems clean and simple, but I’m wary of anything that could react with the foam or break down over time, I don’t love the idea of drilling a bunch of holes in the slab either.
What is best to do
TIA

 

[CircuitGeek]

if you want a permanent solution without drilling, the best route is a foam safe construction adhesive
look for products labeled as 'Polystyrene Compatible' or 'Foam Board Adhesive.'
Brands like Loctite PL 300 or Great Stuff construction adhesive are excellent. The key is to apply it in wavy beads or vertical strips (not full coverage) to let it breathe and cure.
It creates a powerful, permanent bond that won't degrade the foam, and you avoid the future headache of holes in your slab

 

[furg0y]

For foam, I’d stick with a foam safe construction adhesive because it’ll hold well without drilling and won’t eat the material but make sure it’s rated for the type of foam you have, and clamp or weight it while it cures