Simple, rigid, and triangular! The A-frame shape naturally sheds rain and snow while providing a cozy, low-ceiling pocket that holds a cat’s body heat effectively.
+-------------------------------------------------------------+
| ORIGAMI A-FRAME CAT SHELTER |
| |
| /\ |
| / \ [ TRIANGULAR ROOF RIDGE ] |
| / \ |
| / /\ \ [ CIRCULAR ENTRANCE HOLE ] |
| / / \ \ |
| +----+----+ |
| | BOTTOM | [ FOLDS FLAT ALONG RIDGE ] |
| +---------+ |
+-------------------------------------------------------------+
How to Build
- Score a large rectangular sheet of heavy cardboard into three equal sections to form an equilateral triangle.
- Cut a 6-inch circular entrance hole in one end wall.
- Tape waterproof plastic or tarps onto the outer roof panels.
- Fold along the scored center ridge; secure the floor flaps with Velcro strips so it collapses flat when unlatched.

2. Double-Box Insulated Modular Shelter
A box-inside-a-box design that creates an air gap insulating layer, protecting feral cats during freezing winter months.