Simple Outhouse

Build the floor frame from the treated 2x4s — two 72" rails, three 33" cross members. If the ground under it isn't flat and firm the whole footprint, step up to 2x6 for the frame or set it on beams; a floor system is only as good as what it bears on.

Three-inch deck screws, two per joint, and check the frame for square by comparing diagonals.

Screw the seven treated 2x6 deck boards across the frame. The front boards form an exposed entry deck that takes direct rain — this is why the decking is treated stock and not a plywood floor that would delaminate in two seasons.

Each wall is a bottom plate, three studs of stepping heights (80-1/4", 74-1/4", 68-1/4" long points, 15° cut on top), and the 15° top plate tying the slope together. Frame both flat on the deck.

The stepped studs ARE the roof pitch — that's the whole trick of this design. Keep each stud's long point oriented the same way and the top plate lands perfectly.

Attach the plywood side panels with the walls still flat — nailing sheathing on the ground beats nailing it on a ladder every time. The two walls are MIRRORS of each other, not copies: lay them out facing each other before fastening anything.

At the short (rear) end, the plywood overhangs the back framing by 1-1/2" — that overhang closes over the back wall assembly later. Nail off at all edges and intermediate studs.

Stand both walls on the base, screw them down through the bottom plates, and connect them front and back with the 2x4 and 2x6 tie-in pieces. The structure is wobbly until the ties go in, so have a helper or brace one wall plumb while you set the other.

Check plumb on both walls before the final screws — the door gets hung in this opening, and a racked opening means a door that binds forever.

Install the remaining 2x4 supports across the top between the walls. The roof plywood is only 1/2" — it needs bearing every couple of feet or it'll oil-can underfoot the first time someone clears snow off it.

Nail the roof plywood to every tie-in and support it crosses. Then lay the metal roofing over it and drive the gasketed roofing screws through the flats (follow the panel maker's pattern), snug enough to seat the washer without dimpling the tin.

The tin overhangs the high (front) edge slightly so drips fall past the door, not onto it.

Cover the back with the plywood panels — the roof offcut plus a pieced upper panel. The source considered acrylic glazing for the upper back panel for light; plywood is the weathertight default, but a polycarbonate panel there is a legitimate upgrade if the outhouse has no other light source.

Frame the bench with the 2x4 supports and 2x2 rail, top it, and cut the seat opening with the jigsaw — drill a starter hole inside the line first. Sand the opening edge well and round it over; this is one build where nobody forgives a splinter.

Lay the three 1x10s side by side, square them, and screw the three 1x6 battens across at top, middle, and bottom with the 1-1/4" screws. Add the two 37-1/2° braces running from the hinge side down — a board-and-batten door without diagonal bracing sags into a parallelogram within a year.

Hang it on the gate hinges, mount the latch and handle — and then the non-negotiable: drill a hole and run a string to the clasp so the door opens from the inside. Test it yourself, door closed, before anyone else uses the building.