Updated · 6 min read
Written by the Z Construction team, from the projects we price and build in Lee County.
Short answer
In Lee County in 2026 a bedroom or bonus-room addition typically costs $55,000–$95,000 and a primary or in-law suite with a full bath $95,000–$170,000. Selling a home at the county's median listing price and buying another can cost roughly $28,700–$42,200 in commissions and closing costs alone, money that does not stay in any house, plus a higher mortgage rate. If you like your location and your lot can take it, an addition usually wins; if you need a different school zone, much more space or your lot has no room, moving does.
What an addition costs in Lee County (2026)
These are planning ranges for complete, finished space, installed, with permits, foundation, framing, roof tie-in, windows, siding matched to the house, mechanical trades, drywall, trim and paint. The biggest price jumps come from plumbing (a bathroom or kitchenette), a complicated roofline, a sloped lot and whether your HVAC and electrical panel can carry the new space. Try your own size in our addition cost estimator.
| Scope | Standard | Mid-range | Premium |
|---|---|---|---|
| Garage or sunroom — Attached garage, sunroom or screened porch | $34,000–$64,000 | $40,000–$75,000 | $52,000–$97,500 |
| Bedroom or bonus room — Roughly 250–350 sq ft, heated and cooled | $47,000–$81,000 | $55,000–$95,000 | $71,500–$123,500 |
| Primary or in-law suite — Roughly 400–500 sq ft with a full bath | $81,000–$144,500 | $95,000–$170,000 | $123,500–$221,000 |
What moving really costs
To compare honestly, use today's numbers. Realtor.com's median listing price for Lee County was $406,791 in August 2026 (reported on FRED). Redfin found the average U.S. buyer's agent commission was 2.42% in the third quarter of 2025, and commissions are negotiable; if both agents are paid around that rate, commissions on a median sale come to about $19,700. The Consumer Financial Protection Bureau says closing costs typically run 2% to 5% of the purchase price, so a $450,000 next home adds $9,000–$22,500.
- Commissions on the sale: about $19,700 in this example
- Closing costs on the purchase: $9,000–$22,500
- Getting the old house ready to sell: repairs from the buyer's inspection, paint, cleaning
- Movers, overlap in utilities, deposits, and often a few months of two housing payments
- Furnishing and fixing the new house, which rarely fits your furniture or needs exactly
Can your lot take an addition?
This is the question to answer first, before drawings. Every lot has setbacks (minimum distances from the property lines), and most subdivisions have recorded easements and HOA rules on top of city zoning.
- Auburn: the City of Auburn Planning Department can tell you your zoning district and the setbacks that apply, and staff review accessory structures for setbacks too. The building permit then goes through Inspection Services.
- Opelika: if a setback makes a reasonable addition impossible because of a narrow, shallow or oddly shaped lot, the Board of Zoning Adjustment hears variance requests. It meets the second Tuesday of each month, and applications are due to the Planning Department three Tuesdays before.
- Historic districts: exterior changes in Auburn's North College district and Opelika's Northside, Downtown and Geneva Street districts need a Certificate of Appropriateness.
- HOAs: most subdivisions around Auburn and Opelika require architectural review for additions, including rooflines, siding and colors. HOA approval and a city permit are separate; you usually need both.
- Outside city limits: county lots often have more room, but a septic drain field, a well or a steep slope can limit where an addition can go.
How long an addition takes
A move has its own timeline: preparing and listing the house, time on market, a buyer's inspection and financing, then closing and moving. The two are not far apart, but an addition's schedule is mostly in your control.
| Phase | Typical time | What happens |
|---|---|---|
| Feasibility and budget | 1–2 weeks | Site walk, setbacks, planning range before you pay for drawings |
| Design and drawings | Several weeks | Designer or architect, engineering where needed, HOA submittal |
| Permits | Days to a few weeks | Opelika plan review is typically 3–4 business days once complete; Auburn varies with the queue |
| Construction | 6–16 weeks on site | Foundation, framing, dry-in, trades, inspections, finishes |
Living through construction
Most of an addition is built outside the existing house. The disruptive part is the tie-in, when we open the wall between old and new, and the weeks of trades and finishes after it. We plan it so you keep a working kitchen and bathroom, put up dust walls and floor protection, and tell you ahead of time about days when water or power will be off. If the addition connects through the kitchen, it can make sense to update the kitchen at the same time; our kitchen remodel cost guide has those numbers.
When moving is the better call
- You need a different school zone, a shorter commute or a different town, not just more space.
- You need two or three rooms plus a bigger kitchen and garage. At that point you are rebuilding the house.
- Setbacks, easements, the HOA or a septic field leave no good place to build.
- The house has other big bills coming (roof, foundation, HVAC), so the addition would sit on a weak base.
- The addition would make yours the most expensive house on the street by a wide margin. Additions are built for living in; resale rarely pays back the full cost.
A simple way to decide
Before you decide, get a planning number for the addition and a realistic net-proceeds sheet for a sale, side by side. We give a planning range on our first visit to your house, before you pay for drawings, and our home additions page explains how we handle the whole project.
| If this is true | Leans toward |
|---|---|
| You like the neighborhood, schools and commute | Addition |
| Your mortgage rate is well below today's rate | Addition |
| You need one bedroom, a suite or a bonus room | Addition |
| Parents moving in and need a first-floor suite | Addition |
| The lot has room within setbacks and the HOA allows it | Addition |
| You need a different location or school zone | Move |
| You need several rooms and a bigger kitchen | Move |
| The lot or HOA rules block a sensible addition | Move |
| You plan to sell within two or three years | Move, or a smaller project |
Get a written price for home additions
A free walkthrough, a line-by-line estimate in writing, and the owner on the job from start to finish.
Typical 2026 range in Lee County: $40,000–$170,000
Or just leave your number
The owner calls or texts you back, usually the same business day. No spam, no mailing list.
FAQ
Is it cheaper to build an addition or buy a bigger house?
Often the addition, if you need one or two rooms. A bedroom addition runs $55,000–$95,000 here, and that money stays in your house as finished space, while commissions and closing costs on a move do not. If you need much more space or a new location, moving can come out ahead.
How much does a 400 sq ft addition cost in Auburn or Opelika?
A primary or in-law suite of roughly 400–500 sq ft with a full bath typically costs $95,000–$170,000 at mid-range finishes in 2026. Without a bathroom, a bonus room is closer to $55,000–$95,000.
Do I need a permit for a home addition?
Yes, always, from the City of Auburn, the City of Opelika or Lee County depending on the address, plus HOA approval in most subdivisions. See our permit guide.
How close to my property line can I build?
It depends on your zoning district and any subdivision plat or HOA rules. The city planning department can confirm the setbacks for your lot, and we check them on the first site visit.
Can we live in the house during an addition?
Usually yes. Most of the work is outside the existing house until the tie-in. We plan the schedule so you keep a working kitchen and bathroom.
Does an addition add value to my home?
It adds space and usually value, but rarely the full cost at resale. It makes the most sense when you plan to stay for years and it fits the size and price of the homes around you.
Sources
- Consumer Financial Protection Bureau — Figure out how much you want to spend (closing costs)
- Freddie Mac — Primary Mortgage Market Survey (week of Sept. 24, 2026)
- Redfin — Average buyer's agent commission, Q3 2025 (Dec. 8, 2025)
- FRED / Realtor.com — Median Listing Price in Lee County, AL (MEDLISPRI1081)
- City of Opelika — Board of Zoning Adjustment