Home Additions · Auburn · Opelika · Lake Martin

Premium Home Additions in Auburn, AL

Upscale Square Footage with Zero Guesswork

Master suite, bonus room, and second-story home additions for Auburn, Opelika, Lake Martin, and Alexander City — engineered to integrate with the existing structure.

Licensed AL Residential GC · NAICS 236118 Based in Auburn, AL 256-749-6262
Project Photo · 16:9 hero of completed home additions
01 — Overview
What We Build

Home Additions Done Right

A home addition is part new construction, part surgery on the existing house. The roof tie-in, the foundation match, the HVAC capacity, the load path back to the original footings — those are the decisions that determine whether the addition feels like part of the home or a bolt-on.

Old Number One Customs builds master suite additions, bonus room additions, and second-story additions across Auburn, Opelika, Lake Martin, and Alexander City. Each addition starts with a structural review of the existing house before we draw a single line on paper.

02 — Scope
Project Types

Configurations We Build

Master suite additions

New primary bedroom, bathroom, and closet — typically 600-1,200 sq ft. Most common addition type in our market.

Bonus room additions

Garage-bonus, attic-bonus, and over-garage bonus rooms — finished as flex, office, or media space.

Second-story additions

Adding a full second floor or partial second floor when the existing foundation can carry the load. Includes structural engineering.

Sunroom & three-season additions

Heated/cooled additions with floor-to-ceiling glass — used year-round, transition between indoors and outdoor living.

Mother-in-law suites

Self-contained additions with bedroom, bath, kitchenette, and private entrance for multi-generational living.

Garage additions

Attached and detached garage additions with or without finished space above.
Service Area

Serving East-Central Alabama

Old Number One Customs serves homeowners across Lee County, Tallapoosa County, and the Lake Martin region. Most of our work is within 60 minutes of our Auburn office.

  • Auburn
  • Opelika
  • Lake Martin
  • Alexander City
  • Lee County
  • Tallapoosa County
03 — FAQ
Common Questions

What Homeowners Ask

How much does a home addition cost in Auburn, AL?

Most home additions in Auburn and Opelika run $300 to $500 per square foot all-in, including finishes. A 600 sq ft master suite addition typically lands $180,000 to $320,000. Use the configurator for a tier-based estimate scoped to your project.

How long does a home addition take?

Four to seven months from breaking ground to final inspection. The biggest schedule drivers are design and permitting (often 6-10 weeks before construction starts), and any structural engineering needed for the tie-in.

Do I need an architect for a home addition?

Most additions in the Auburn-Opelika market don't require a stamped architectural drawing — we work with residential designers for the plans and bring in a structural engineer for any framing that needs a stamp. Larger additions or historic district work require a licensed architect.

Can you match the existing exterior of my home?

Yes — this is one of the biggest tells of a good addition. We match siding profile, brick coursing, roof pitch, fascia, soffit, and window manufacturer. If the existing siding is no longer manufactured, we'll source close matches and stage the transition so it doesn't read as new.

Can you build additions on Lake Martin?

Yes. We serve Lake Martin and Alexander City. Lake home additions often involve coordinating with Alabama Power shoreline permits and working around seasonal access for vacation owners.
Start Your Project

Get a Tier-Based Estimate

Use our project configurator for a real-time estimate scoped to your address, project type, and finish level. No sales call required to see a number.