What drawings do I need for a home addition permit?

Usually a site plan with setbacks, existing and proposed floor plans, exterior elevations of the sides that change, and a building section. Many places also need structural drawings or calculations, which an engineer prepares.

Can I draw the plans for my own addition?

Some places accept owner-drawn plans for a small single-storey addition; many require a licensed designer or engineer for additions, especially for structure. DrawPlans makes the drawings to scale either way, and a DXF export lets a designer carry on in CAD.

How do I show where the addition goes on my lot?

Draw the property lines and the house, turn on the site plan and enter the setbacks. Then draw the addition: anything inside a setback shows in red, and lot coverage is worked out as you draw.

Will the elevations show the addition's roof?

Yes, once you add a roof over it in the Plan panel (gable, hip, shed or flat). The exterior elevations and building sections draw it from its settings.

Home addition permit drawings

An addition, a new bedroom, a bigger kitchen or a sunroom, almost always needs a building permit, and the drawings have to show the house as it is, what's being added, and how the addition sits on the lot.

Start from the two-bedroom house template (or draw your own house), save a copy, and draw the addition onto the copy. The elevations and sections redraw from the plan as you go.

See pricing

Drawings usually requested

What building departments commonly ask for with this kind of project. Each links to how to make it in DrawPlans.

Site plan with setbacksThe lot from its property lines, the building on it, the setback lines and the distance to each lot line.
Existing and proposed floor plansThe space as it is today and as it will be, as two plans (save a copy of the plan before you change it).
Exterior elevationsEach side of the building with its doors, windows, roof and heights.
Building sectionA cut through the building: wall and ceiling heights, the floor, and the roof.
Door and window scheduleEach door and window marked on the plan with its size, in a table.
A PDF set at a stated scaleThe drawings as PDF pages with a title block and a scale bar, or a DXF for a designer's CAD program.

For an addition, check the setbacks and lot coverage first: the site plan shows how much room the lot leaves, before you draw the new rooms.

Example drawings

Drawn by DrawPlans from the templates below, exactly as it exports them.

Floor plan of a 40' × 28' two-bedroom house drawn to scale: living room, kitchen and dining, two bedrooms, hall and bathroom with wall lengths — The two-bedroom house template: draw the existing house, then the addition beside it.

Front exterior elevation of the two-bedroom house with a gable roof added: two windows and the front door, level marks and the overall width and height — Front elevation of the house, with a gable roof added in DrawPlans.

Building section across the two-bedroom house: cut walls with window openings, floor slab, gable roof with overhangs, room names and level marks — Building section across the house: where a new room's floor and roof meet the old.

How to make the drawings

Start from the two-bedroom house templateOpen the two-bedroom house template, or draw your own building from scratch. It becomes your own plan, saved to your account.
Change it to your projectType your real wall lengths, move or resize the doors and windows, and add the roof in the Plan panel. The elevations and sections redraw from the plan.
Add the site plan and setbacksDraw the property lines from your survey, turn on the site plan and enter the setbacks: the distances to each lot line and the lot coverage are worked out for you.
Export the PDF setAdd the elevations and sections to PDF exports, then export one PDF with the floor plan, site plan, elevations, sections and schedules, each at a stated scale.

Which plan fits

14-day pass: $12.99 one time

For one quick project. Doesn't renew.

For one project of your own: draw it, then download the PDF set and any other files while the pass lasts.

Monthly: $9.99 per month · Yearly: $79.99 per year

For designers, builders and contractors with project after project. Also includes client proposals (PDF): your plan, AI renders, schedules and cost estimate in one branded document.

You can draw one plan and see it in 3D before paying. See pricing

Questions

What drawings do I need for a home addition permit?: Usually a site plan with setbacks, existing and proposed floor plans, exterior elevations of the sides that change, and a building section. Many places also need structural drawings or calculations, which an engineer prepares.
Can I draw the plans for my own addition?: Some places accept owner-drawn plans for a small single-storey addition; many require a licensed designer or engineer for additions, especially for structure. DrawPlans makes the drawings to scale either way, and a DXF export lets a designer carry on in CAD.
How do I show where the addition goes on my lot?: Draw the property lines and the house, turn on the site plan and enter the setbacks. Then draw the addition: anything inside a setback shows in red, and lot coverage is worked out as you draw.
Will the elevations show the addition's roof?: Yes, once you add a roof over it in the Plan panel (gable, hip, shed or flat). The exterior elevations and building sections draw it from its settings.