How to Build Folded Cardstock Ruins with a Miniature-Supporting Upper Floor
To build a cardstock ruin whose upper floor can hold miniatures, give the floor continuous support along its edges and at least one support beneath its open span. Folded cardstock can form these ledges, ribs and columns without adding bulky materials. Measure around the miniatures you plan to use, score folds before assembly, let glued joints dry, and test the finished floor with the actual figures before adding decoration.
Plan the footprint around play
Set the miniatures on a sheet of scrap paper and arrange them as they would stand in the upper room. Mark the area their bases need, then sketch the ruin walls around it. Leave space to place and lift figures: a floor that fits the walls but traps fingers or bases is awkward during play. A partial upper floor is often easier to access than a full ceiling-like platform.
Decide where the floor will be removable. For a ruin with open sides, a loose floor resting on ledges makes it easier to reach the lower level. If you want it fixed in place, leave an opening large enough to handle the figures. Paper terrain makers commonly score cardstock folds before assembly, and a tabletop building guide describes removable upper floors supported by internal walls or ledges. Those are useful starting points; the exact dimensions should follow your miniatures and room layout. Johansome’s Printable Terrain – Tower and Ruins and Wargame scenery and terrain – Buildings
Choose cardstock and make clean folds
Use cardstock that holds a sharp fold without cracking badly. If you have a paper terrain pattern, follow its material guidance; one printable terrain maker recommends 60 lb cardstock or heavier paper and notes that scoring helps assembly. Test a small offcut first, since thickness and coating vary. For a homemade design, use the same stock for the main walls and floor so the tabs and ledges fit consistently.
Mark fold lines lightly and score them with a blunt scoring tool or the back of a knife against a ruler. Score only deeply enough to guide the fold, without cutting through the sheet. Fold over the ruler edge for a straight crease. A cardstock building guide specifically recommends gentle folds and using a ruler to guide heavy card, noting that sharp folds can damage the printed surface. Building Assembly Guide
Fold ledges into the walls
Make a narrow inward-facing flange along the inside of each wall that will carry the floor. The floor should rest on these flanges rather than hang from a thin glued edge. Use a continuous ledge where possible; if the ruin has broken walls, add short ledges on the remaining wall sections and support the exposed floor edge with a folded beam or column beneath it.
For each ledge, cut a strip of cardstock, score a lengthwise fold to create an L-shaped section, and glue one face against the wall. Folded corners give the strip more stiffness than a flat strip, while the second face provides a wider surface for the floor to sit on. Add small triangular gussets at corners if the wall and ledge flex under gentle pressure. Let the glue set before placing the floor. This L-section and gusset approach is a practical design inference from the need for a wider bearing surface and braced joints; it is not a tested load rating.
Reinforce the floor span
Cut the floor panel so it rests on the ledges without forcing the walls apart. Underneath, glue one or more folded ribs across the open span. A simple rib is a long strip folded into a shallow channel or box shape, with a small glue tab along each side. Position ribs beneath likely miniature standing areas, and orient them so the floor cannot sag freely between supports.
If the floor is broad, add a second rib or a folded beam beneath a free edge. You can also use a folded column that reaches from the base to the underside of the floor, placed where it fits the ruin’s look and does not block access. As a comparison, a terrain tutorial supports floors on strips fixed to walls, while a building guide describes internal walls and ledges as support for removable floors. The folded ribs and columns here adapt that supported-floor principle to a cardstock-only build. Miniature Fort UK’s Foamcore Ruins Part 1 – Basics and Wargame scenery and terrain – Buildings
Assemble square, then test before detailing
Dry-fit the walls and floor first. Check that the ledges sit at the same height and that the floor lands on each intended support. Glue the wall tabs, hold the corners square while they set, and attach the floor only after the walls are stable. If the floor is removable, keep enough clearance that it lifts out without scraping the interior supports.
Test in stages: first press lightly at the center of the empty floor, then place one miniature on it, then add the rest of the figures you expect to use. Watch for bending, a ledge peeling away, a wall leaning, or a floor panel rocking. If any movement appears, remove the figures and add a rib, a support under the weak area, or a wider ledge before trying again. This is a practical fit check for your particular materials and construction, not a guarantee for every cardstock weight or glue.
Add ruined edges without weakening supports
Once the structure passes the figure test, trim the upper walls into broken silhouettes and add surface details. Keep cuts away from the glue tabs, ledges, rib ends and wall corners that carry the floor. Cap exposed corrugation or layered edges with narrow card strips if needed, and keep rubble texture off the miniature standing area so bases sit flat.
Paint and glue can add moisture, so apply them sparingly and allow the model to dry fully before retesting. If the floor develops a curl, reinforce its underside with another folded rib or replace it with a smaller panel. For a large span or especially heavy miniatures, cardstock alone may not stay flat; shorten the span with another support or choose a sturdier material for the hidden structure.