How to Build Wargaming Terrain with XPS Foam
XPS foam is one of the most versatile and beginner-friendly materials in the terrain builder's toolkit. Lightweight, easy to cut, and capable of holding incredible surface detail, it's the go-to choice for hobbyists building everything from ruined walls to dungeon corridors. This guide walks you through the essentials — from choosing the right foam to finishing your piece to a tabletop-ready standard.
Why XPS Foam?
Unlike polystyrene (the white, beady stuff), XPS (extruded polystyrene) foam has a smooth, closed-cell structure that holds crisp edges and accepts paint without dissolving. It's rigid enough to hold its shape but soft enough to carve, score, and texture with basic tools. Whether you're building a single scatter piece or a full modular board, XPS foam gives you the control and consistency to work at any scale.
What You'll Need
- XPS foam sheets or pre-cut bricks
- A sharp hobby knife or hot wire cutter
- A ballpoint pen or sculpting tool for texturing
- PVA glue and/or contact adhesive
- Acrylic paints and a stiff brush for drybrushing
- Sand, grit, or fine ballast for basing
Step 1 — Plan Your Build
Sketch your piece before you cut. Even a rough thumbnail helps you think through proportions, wall heights, and how components will stack or interlock. For modular terrain, decide on a consistent base unit size so pieces work together across your collection.
Step 2 — Cut Your Foam
For straight cuts, score deeply with a sharp knife and snap cleanly. For curves or complex shapes, a hot wire cutter gives smooth, controlled results. XPS Craft Foam Sheets are available in multiple sizes — the 400mm × 300mm sheet is ideal for medium-sized terrain pieces, while the 600mm × 400mm sheet suits larger builds like fortress walls or multi-level ruins.
If you're working with pre-cut forms, XPS Foam Bricks are a fast way to build up walls and structures without cutting every block from scratch. Stack, stagger, and glue with PVA for a convincing masonry effect.
Step 3 — Add Texture
This is where XPS foam really shines. Use a ballpoint pen to scribe stone block lines, brick courses, or flagstone patterns directly into the surface. A crumpled ball of foil pressed firmly into the foam creates a rough rock or rubble texture. For wood grain, drag a stiff wire brush along the surface. Work in layers — rough texture first, finer detail on top.
Step 4 — Seal and Prime
XPS foam is sensitive to solvent-based sprays, which will melt the surface. Always use a water-based primer or brush on a coat of diluted PVA before spray priming. Once sealed, the foam accepts any acrylic paint without issue.
Step 5 — Paint and Weather
Start with a dark basecoat — black or dark grey works well for stone. Drybrush progressively lighter shades to pick out the texture, then add washes to deepen recesses. For weathering, stipple on rust tones, add chipped paint effects with a sponge, or apply pigment powders for dust and grime. The more layers you add, the more convincing the result.
Step 6 — Base and Finish
Glue your terrain piece to a base of thick card, MDF, or foam board. Apply PVA around the edges and scatter fine sand or grit for a natural ground texture. Once dry, paint and flock to match your gaming table.
XPS foam rewards patience and experimentation. Start simple — a ruined wall section or a rocky outcrop — and build your skills before tackling larger, more complex pieces. The material is forgiving, inexpensive, and endlessly adaptable.
Ready to start building? Browse our full range of XPS Craft Foam Sheets and XPS Foam Bricks at MTG Terrain & Scenery.