Foldable Modular House

This project guides you through on how to design a minimalist foldable house made entirely from cardboard and paper scoring techniques. This model uses clean geometric shapes, angled folds, and modular pieces to give it a modern architectural look. The whole structure is made from a single flat sheet that folds into a 3D house, plus a few add-on modules.

Materials needed

1. Medium-thickness cardboard
2. Cutting board
3. Letter paper (for template)
4. Pencil (for marking)
5. Metal ruler
6. Pen knife / X-acto
7. Scissors
8. Tape/Masking tape
9. Glue/Wood glue

Lay out your cardboard, knife, ruler, and tape.

It is best to choose a cardboard sheet that’s not too thick, so it folds easily.

We decided to use a white photographic cardboard as it's quite thick and also cuts nicely.

Instead of a regular house shape, design something abstract + geometric.

Recommended styles that fold easily:

1. A-frame house with a dramatic angled roof
2. Cube house with a cool cut-out wall
3. Slope-roof studio with one long diagonal fold
4. Z-fold modern villa (looks complex but is very easy)

For us, our house will be a two-story stacked foldable modular house.

Your template should include:

1. Outer cutting lines
2. Inner fold lines
3. Tab connections

Make sure fold lines are different from cut lines (dotted vs solid).

Now you can start to draw the baseplate of your modular house onto the cardboard of your choice.

Transfer your design onto the cardboard using either:

1. A printed paper layout taped on top
2. Or drawing directly with pencil and ruler

Your template should include:

1. Outer cutting lines
2. Inner fold lines
3. Tab connections

Make sure fold lines are different from cut lines (dotted vs solid).

Use your ruler + knife to cleanly cut the outer shape.

You can then cut the inner windows, doors, and other details that you would like to include.

Scoring the fold lines:

This is the most important part of the project.

Scoring means cutting lightly so the cardboard bends without breaking.

To score:

1. Place the metal ruler along the dotted fold line.
2. Apply very light pressure with the knife.
3. You should only slice the top layer, not all the way through.

If you cut too deep, the wall will rip instead of folding cleanly.

Practice scoring on a scrap piece if needed.

This will allow the walls and roof to fold crisply.

Bend along the scored lines, and try to fold it into the shape that you planned beforehand.

You should get something like:

1. Walls folding up
2. Roof folding over
3. Folds inward/half cut through

OPTIONAL:

If your design has an angled roof, score the roof line lightly so it folds smoothly.

In our case we decided to use tape for the main floor, and glue for the second floor

Once all folds are aligned:

1. Use exterior tape to connect the ends together
2. Put glue on the top surface of the first floor and then join it to the second floor.

When taping the first floor:

1. Apply tape on the outside
2. Press firmly along each seam to ensure the tape bonds well
3. If you want a cleaner look, wrap the tape around the edges so it hides underneath the model

When gluing the second floor:

1. Spread a thin, even layer of glue on the first floor’s top surface
2. Position the second floor slowly and carefully, making sure all sides sit flush
3. Apply pressure on the corners so the floors bond evenly as the glue dries

Tip: place a small book on top while the glue dries to prevent lifting.

You should now have a stable structure that's sturdy and balanced.

Use your leftover cardboard to cut one large rectangular piece.

Place it so that it sits on top of the first floor and extends outward from the main house volume.

This piece acts as:

1. A balcony for the second floor
2. A flat roof over the garage area
3. A horizontal platform that adds modern architectural style

Adjust the size until the extension lines up cleanly with the house edges. Once you're satisfied, secure it with tape or glue it in place.

To ensure the platform sits flat:

1. align it with the second floor, so the transition between the second floor and the balcony remains smooth
2. Check from multiple angles (front, side, top)

If the balcony is large, reinforce the underside using a small strip of cardboard glued horizontally along the edge. This acts like a hidden structural beam that prevents bending over time.

Once fully attached, this balcony/roof becomes one of the main visual features of the model and gives it a distinctive modern architectural character.

Cut several long, thin strips of cardboard to be used as vertical support legs.

These will support the extended balcony/roof.

1. Trim each strip to equal length.
2. Fold the bottom of each leg slightly to create a small foot for gluing.
3. Attach the legs under the outer edge of the balcony/roof.

Before attaching the legs, test the height by placing the balcony/roof piece flat and sliding the strips underneath. This ensures all legs touch the ground evenly, preventing wobbling.

When shaping the legs:

1. Keep them narrow for a modern, lightweight look
2. If you want a stronger structure, fold each leg into multiple layers to reinforce

When attaching them:

1. Apply glue to both the “foot” of the leg and the underside of the balcony
2. Hold each leg in place for a few seconds to let the glue grip
3. Check from the front and side to make sure the legs are straight and vertically aligned
4. Place legs evenly apart so the structure looks balanced and intentional

💡 Tip: Adding 2 to 3 legs usually look best. Too many could make the design messy, but it's up to you.

Once the glue dries, your balcony should feel much more stable, and the completed legs add an architectural detail that visually anchors your design to the ground.

Now that your main structure is complete, it’s time to bring your cardboard house to life with creative details!

This step is all about adding personality and realism to your model.

We decided to add balcony fences, cooler roofs, colors to contrast, and some other fine details to make it look better.

Here are some few ideas:

1. Fences & Railings: Use thin strips of cardboard or toothpicks to build fences, balcony railings, or garden borders.
2. Stairs or Ladders: Cut small rectangles and stack them to form stairs, or glue thin sticks together for a rustic ladder.
3. Pathways: Create walkways using textured paper, sandpaper, or painted cardboard pieces to mimic stone or tiles.
4. Furniture & Accessories: Make tiny chairs, tables, or potted plants from leftover cardboard scraps. You can even add curtains, doors, or a mailbox for extra charm.
5. Color & Texture: Paint or decorate your house with markers, colored paper, or patterned fabric to give it a finished look.

Take your time with this step and add anything you like or imagine. The sky is the limit.

And you're done!

Here is what our house looks like if you would want to take inspiration or add onto.