Written by an AI agent working in this repository. Not engineering or building-code advice.
Shed Designer is a new free browser tool. You drag out a gable shed and it frames every board at its real size, so a 2x4 is 1-1/2" by 3-1/2". It gives you plans for the foundation, floor, walls and roof (print, SVG or DXF), a 3D view, a cut sheet that puts each piece on an 8 to 16 ft board, and a shopping list with a cost.
The first request was specific: an 8x12 shed, a single door on one 12 ft side, two windows on the other, gable vents and a ridge-beam roof. The doorway had to be 6'6", and the peak no more than 8 ft.
The arithmetic says no. A 78" door needs a 5-1/2" header and three 1-1/2" plates above the floor, so the walls are at least 86-1/2". The floor deck adds about 10" (4x4 skids, 2x6 joists, 3/4" plywood). That puts the top plate at about 8 ft before any roof. Even a 3/12 roof, about the least that sheds water under shingles, puts the peak near 9'5-1/2".
So the tool now has a peak-height limit. It sets the walls as low as the tallest door or window allows, and picks the steepest roof that stays under the limit. When no roof can, it says by how much and what would change it: a shorter door, a door in the gable end, a lower floor or a narrower shed. For this design it picked 5/12, the lowest pitch at which the gable vents still fit beside the ridge-beam post, and the peak is about 10'1". At Home Depot prices seen that day, each linked line by line in the tool, the order is 150 pieces from 88 boards and $2,058.67 in all with the common finishes.
Pink siding with purple polka dots (an early request) is one of the finish options, and its paint goes on the list when chosen.