Draw a Permit-Ready Gable Roof in ArchiMaster 3D

To draw a permit-ready gable roof in ArchiMaster 3D, open the Roof tab, select Gable, set pitch to 6:12, enter 18–24 inches for eave overhang and 12 inches for gable overhang, then snap the roof to your exterior wall lines. Those settings place the overhang lines exactly where a residential plan reviewer expects them on a roof plan, and they keep the ridge height predictable when you dimension the front elevation. The roof tool generates from wall top plates, so the first task is not drawing the roof; it is setting the wall height correctly. If you are new to this tool, the 3D home design feature overview shows how the roof module connects to your floor plan and materials.

• Set eave overhang to 18–24 inches and gable overhang to 12 inches before you export roof plan views.
• The roof tool builds from wall top plates, so set floor-to-plate height first or the ridge height will be wrong.
• Use a pitch between 4:12 and 9:12 for most residential permit drawings; 6:12 is a safe default.
• Snap the roof perimeter to the outside face of exterior walls to create the gable end automatically.
• Export plan, front elevation, and side elevation as separate PDF pages with scale locked at 1/4 in. = 1 ft.

“A roof plan passes review because the overhang is dimensioned to the sheathing, not because the 3D model looks good.”, ArchiMaster 3D Journal

Set Wall Height and Plate Height Before You Draw the Roof

The ArchiMaster 3D roof tool generates from your model's wall top plates, not from the floor line. If a wall is drawn at 8 feet but the real framed wall rises to 8 ft 1 1/8 in. because of the sole plate and double top plate, your ridge height will be low by that same amount. Fix the wall height first. For a standard 8-foot ceiling, set each exterior wall's height to 8 ft 1 1/8 in. (97 1/8 in.). For a 9-foot ceiling, use 9 ft 1 1/8 in.

After setting wall height, open a section view and confirm the top plate line sits at the intended elevation. A one-inch error at the plate becomes a larger error at the ridge on a 12:12 roof. This step matters for planning permission drawings because reviewers check ridge height against the zoning schedule, not against your ceiling height. The ArchiMaster 3D suite includes the roof tool in the home design editions, so check the edition comparison if you need DWG export for a plan reviewer.

Step-by-Step: Build a Gable Roof in ArchiMaster 3D

• Open your plan in 2D Plan view and make sure the exterior walls form a closed polygon.
• Click the Roof tab, then choose Gable Roof from the roof type selector.
• In the roof dialog, set Roof Pitch to 6:12 for a balanced, widely accepted residential slope.
• Set Eave Overhang to 24 in. for a deep eave or 18 in. for a tighter roof line.
• Set Gable Overhang to 12 in. This creates the raked edge shown on the gable-end elevation.
• Click OK, then snap the roof perimeter to the outside face of the exterior wall lines.

ArchiMaster 3D treats the roof as a single parametric object after placement. If you later change the wall length, select the roof and click Rebuild to regenerate the gable ends. If the plan is an L-shape, build the main wing first, then use the same Gable command on the secondary wing and merge the roofs. The merge tool keeps the ridge and valley lines clean, which is exactly what a roof plan needs to show.

Set Overhang Dimensions That Pass Plan Review

Eave overhang and gable overhang are two separate fields in the roof dialog. Set eave overhang to 18–24 inches. This dimension is measured from the exterior face of the wall sheathing to the outside edge of the fascia, not to the gutter. Set gable overhang to 12 inches. The gable overhang creates the triangular rake line on the end wall and is drawn on the gable-end elevation.

Most residential review checklists accept an eave overhang of 16–24 inches and a gable overhang of 12–18 inches. Use a 24-inch eave overhang when the site is in a heavy rain or snow region and you plan to show gutters on the elevations. Do not include the gutter in the roof overhang number. The gutter hangs outside the fascia and belongs in the elevation detail, not in the roof plan dimension.

Add Pitch, Ridge Height, and Overhang Dimensions

After the roof is placed, use the Dimension tool in ArchiMaster 3D to place three critical callouts. First, dimension from the exterior wall face to the fascia on the plan view to show the eave overhang. Second, dimension the gable overhang on the end wall. Third, place a pitch label on each roof plane. Most planning departments require pitch as a ratio, such as 6:12, shown with an arrow up the slope.

For ridge height, open a front elevation or a section view and dimension from finished grade to the underside of the ridge beam. Do not dimension to the top of the shingle surface. If your ridge height exceeds the local limit, lower the pitch before you start moving overhangs. A steeper pitch raises the ridge much faster than an overhang change does. For a complete interior remodeling permit package, pair this roof setup with the process in How to Design a Permit-Ready Kitchen in ArchiMaster 3D (2026). The roof plan and the kitchen plan share the same wall and dimension layer, so both exports stay consistent.

Export Plan, Elevation, and Section Views

A roof permit set needs three views from ArchiMaster 3D: the 2D plan view showing the roof perimeter, overhangs, and pitch labels; the front elevation showing the gable rake and ridge height; and a side elevation showing the eave overhang in profile. Use File > Export, then choose PDF for a single-sheet set or DWG if your plan reviewer asks for CAD.

Use the same scale across all sheets

Set the export scale to 1/4 in. = 1 ft. for residential roof plans. Use 1/8 in. = 1 ft. only for site plans. When the scale is locked in ArchiMaster 3D, the dimensions you placed in the model carry through to the printed page at their true value. If the export is set to Fit to Page, the dimension values remain correct, but the drawn line lengths can look shorter than the labels, which creates an avoidable review comment.