While there are several easy ways to build a doghouse, owners with minimal woodworking skills and tools can build a simple A-frame roof structure from a single sheet of 3/4-inch exterior-grade plywood, an 8-foot 2x4 and a 6-foot 2x2. Cover the roof with roofing paper and shingles to provide a dry place for a dog weighing up to 50 pounds.
Layout the plans on the plywood. Use a marker, framing square and straight edge to draw all cutting lines on the wood. Use a plate or similar round object to mark the rounded top of the door. Choose to cut along the lines or outside them, but be consistent for the entire project.
Build a base using the 2x4 lumber. Cut two lengths 22 1/2 inches and two 23 inches. Attach the 2x4s with 3-inch wood screws to make a box, and then attach the floor of the dog house to the base, making sure it is square. The base lifts the floor off the ground, so the interior remains dry and provides a dead space of air to help keep the pet warm.
Attach the walls to the base and to each other. Apply the roof panels and roofing. Paint the doghouse with exterior-grade paint to protect the wood from the elements.