How to Glue Insulation Foam: Adhesive Guide

Insulation foam (or XPS) is incredibly useful and popular for cosplay thanks to its light weight and ability to hold a rigid shape. It’s perfect for plenty of different applications, including large props you can carry around all day, horns and headwear, costume details, and more. However, insulation foam can be kind of tricky to build with because of the way it can react to some glues and adhesives. If you want to keep your insulation foam from melting and breaking down, you need to know which adhesives are safe to use. In this post, we’ll explain how to glue insulation foam with the best adhesives for the material and discuss how some other glues can break down the foam.

Best Glues for Insulation Foam

Cosplayer using Attach & Build double-sided sheets to adhere insulation foam

  1. Attach & Build double-sided sheets: Attach & Build is a double-sided, peel and stick adhesive sheet that works with almost any cosplay material, including insulation foam. Attach & Build is non-toxic and won’t cause a negative reaction with the foam. You can cut the sheets to any size or shape, then just peel and stick for an instant bond between foam pieces or foam and other materials. Attach & Build is a great solution when working with one or more tricky materials.
  2. Spray adhesive: Spray adhesives (like ones from 3M or Elmer’s) are ideal for building with insulation foam. First of all, spray glue won’t react negatively with your foam, so that’s a plus. At the same time, spray adhesive allows you to cover large areas with glue relatively quickly, so it can be especially useful for those large, lightweight weapon/prop builds and for sandwiching foam together to make thicker layers. Another benefit of spray glue is that it won’t add much weight or any thickness to your foam because the formula is pretty thin but also pretty strong. Side note: you’ll want to be careful when spraying or cover your work area with something disposable like newspaper because any overspray will basically make your supplies or table permanently sticky.
  3. Mod Podge: If you want to stack layers of insulation foam to create a thicker sheet, Mod Podge is also a good adhesive option for you. Mod Podge is like a slightly less intense version of contact cement, and it plays pretty nicely with insulation foam. Mod Podge can also be used to seal insulation foam before painting, though it doesn’t add much strength or reinforcement to the foam.
  4. Wood glue: Another option is wood glue. Because wood glue is also non-reactive for insulation foam, it can be used both to glue pieces together and to seal before painting. Because wood glue usually comes in a bottle, it can be pretty convenient for gluing smaller foam details or for filling in small gaps between your foam pieces.

    Cosplayer using hot glue on insulation foam axe head

  5. Hot glue: Finally, one more adhesive choice for insulation foam is hot glue, but this option comes with conditions. Hot glue does work with insulation foam, but it can also melt the foam a bit. Because this is purely a result of the heat from the glue and not a chemical reaction, the melting will only last few a few seconds before the glue cools. Because of this, you can use hot glue in places that won’t show, like handle pockets that you’ve routed out for props and weapons.

Insulation Foam and Adhesive Reactions

While the adhesives we listed above (and potentially others) can be incredibly effective for different insulation foam builds, several other adhesives can cause negative reactions that break down your insulation foam and can ruin your cosplay. For one thing, while contact cement is an ideal adhesive option for EVA, L200, and craft foams, it will eat away at insulation foam almost instantly. Most super glues (or CA glues) also cause insulation foam to break down and disappear, creating holes or indents in your cosplay or prop. Using too much hot glue in conspicuous areas can also lead to indents and weak areas in your insulation foam, so we’d only recommend using hot glue in very hidden areas if necessary. As long as you watch out for these adhesives that cause reactions, you should have no problem building amazing props and cosplays using insulation foam.