Foam & Prop BuildingNo. 6182 · The 2026 edition
Halloween Arch
Transform your entryway into a spooky stone gateway with this DIY Halloween arch project. Using simple materials like foam, paint, and basic tools, you can create a realistic, weathered brick wall tha
Our own summary of the original — the full post and photos live at myfunhouseprojects.blogspot.com.
This project guides you through carving a 2-inch styrofoam block into a brick arch, securing it to a 2x4 backing, and layering water-based and solvent-based paints to achieve a realistic stone texture. The final steps involve adding putty, decorative elements like skulls and chains, and concealing the frame with shredded plastic bags for a polished, haunted appearance.
You'll need
Directions
- Sketch your design on paper to visualize the final arch.
- Purchase a block of 2-inch thick styrofoam from a local hardware retailer.
- Carve brick patterns into the foam using a plunge router bit.
- Smooth the bottom edges of the solid sections with the router to mimic poured concrete.
- Shape decorative bones using a Dremel rotary tool.
- Test your paint choices on a small foam scrap to check the finish.
- Apply solvent-based paint to the mortar lines, allowing it to slightly dissolve the foam for a weathered texture.
- Construct a simple frame using a 2x4 board, then attach the foam block with wood glue and screws.
- Secure the upper arch sections with wire while the adhesive sets.
- Fill any gaps or seams with wood putty.
- Paint the mortar lines black using one pint of water-based paint, then mask the areas to protect them.
- Apply a base coat of gray water-based latex paint, using one quart.
- Add depth and age by spraying matte black paint over the surface.
- Finish with two coats of stone-textured paint, requiring two cans.
- Note that the water-based latex layer shields the foam from damage when applying solvent-based paints later.
- Tuck shredded plastic bags behind the structure to conceal the wooden frame and any gaps against the wall.
- Attach purchased decorations, including skulls, chains, and a 'Beware!' sign, to complete the look.
More photos
Photos hosted by myfunhouseprojects.blogspot.com.