Insulating Concrete Form (ICF) Walls
Once in a blue moon, we get a question about installing to ICF walls. The inside wall of an ICF wall is drywall on Styrofoam/Polystyrene.
Now, if the drywall is 5/8 thick you can use our EZ load drywall anchors (though the load capacity is reduced substantially).
However, if you want to have a shelf with any significant loading capacity, you will need to attach the male bracket to the concrete, with the appropriate anchors. That would mean that cutting the drywall and the Styrofoam out until you get to the concrete.
Just making deep holes and attaching it to the concrete will do nothing, since as soon as you tighten the screws, the male bracket would crack the drywall and just squeeze the Styrofoam together. Now, if you have 2 x 4’s on the Styrofoam and the drywall is attached to the 2 x 4’s - Then it would basically just become a normal install - which simplifies things greatly. This may be the best option here if you want to pursue an installation of this nature.