First: how wide can you actually build?
Lot width isn't your building width. Subtract the side setbacks — the required distance from each side property line — and that's your buildable envelope.
| Lot width | Side setbacks (example) | Max house width |
|---|---|---|
| 40 ft | 5 ft each side | 30 ft |
| 50 ft | 5 ft + 7.5 ft | 37.5 ft |
| 60 ft | 7.5 ft each side | 45 ft |
Setbacks vary by city and zoning district, and corner lots often have a larger street-side setback. Get the real numbers from your zoning code or a survey before any design work — see setback requirements. Also check eaves, porches and chimneys: some codes let them project into the setback, some don't.
6 ways to narrow a house plan
- Take width out of the widest rooms. Great rooms and primary suites often have 2–4 feet to spare. Trimming them along one line can narrow the whole house without losing function.
- Go deeper. Move a room from the side to the back. A 60′-wide, 40′-deep ranch can become a 44′-wide, 55′-deep plan with the same square footage.
- Go up. Move secondary bedrooms upstairs. A 1½- or 2-story version of a ranch can cut the footprint by a third or more. Compare costs in single-story vs. two-story.
- Remove bump-outs. Bay windows, side porches and jogs that project past the main walls often push a plan over the setback line.
- Rethink the hallway. A central hall down a long house wastes less width than a side corridor plus a separate foyer.
- Turn or move the garage. Usually the biggest single win — see below.
The garage problem
A front-load 2-car garage takes 20–24 feet of a narrow lot's width. Options, from least to most change:
| Option | Width used | Trade-off |
|---|---|---|
| Tandem garage (2 cars nose-to-tail) | 12–14 ft | One car blocks the other |
| Rear-load garage off an alley | Out of the front façade | Needs alley access |
| Detached garage in the back | Driveway only, ~10–12 ft | Longer driveway, walk to the house |
| Single-car garage + carport or pad | 12–14 ft | Less covered parking |
Moving the garage usually also moves the mudroom, laundry and entry, so we treat it as part of the same modification. More garage options: how to change the garage on a house plan.
Keeping light in a long, narrow house
A narrow house has short front and back walls and long side walls that often face a neighbor 10–15 feet away. Good narrow-lot modifications plan for light and privacy:
- Clerestory and high windows on side walls — light in, no view of the neighbor's kitchen.
- Open living area at the back with large glass facing the yard.
- A side courtyard or notch in the middle of a long plan to bring light into central rooms.
- Vaulted ceilings in the main living space to offset a narrower room.
- Fire-rated walls where the house sits close to the property line — codes limit openings in walls very near the line.
Typical front, side and rear setbacks — and how to find the exact numbers for your lot.
Read the setback guideWhat narrowing a plan costs
| Change | Our package |
|---|---|
| Trim room widths, remove bump-outs | Standard Modification — $599 |
| Move or change the garage, reshape into a deeper plan | Standard Modification — $599 |
| Convert a ranch into a 1½- or 2-story plan | Major Plan Redesign — from $999 |
A narrower, simpler footprint is often cheaper to build: fewer corners, a simpler roof. See how house shape affects cost.
How to get your plan fitted to your lot
- Upload your plan and your lot info — a survey or plat is best, lot width and setbacks are the minimum.
- Tell us what matters most: keeping it single-story, the garage, the yard, the views.
- We confirm scope within 1 business day with a target building width.
- We redraw the plan to fit, with two revision rounds included.
Frequently asked questions
Can you make a house plan narrower?
Yes. We trim room widths, move rooms to the back or upstairs, remove bump-outs and rethink the garage so the plan fits inside your side setbacks.
How do I know how wide my house can be?
Subtract both side setbacks from your lot width. Setbacks come from your local zoning code or survey; corner lots usually have a larger setback on the street side.
What is the best garage for a narrow lot?
Rear-load off an alley is ideal. Without an alley, a tandem garage or a detached garage behind the house saves the most width.
How much does it cost to modify a plan for a narrow lot?
Most narrow-lot changes are a Standard Modification at $599. Turning a ranch into a two-story plan is a Major Plan Redesign from $999.
Can you modify a plan I bought from another website?
Yes — provided you own the plan or have permission / the right to modify it.