Home Additions on the North Shore and in Lake County

Home Additions on the North Shore and in Lake County

J & M Elite Renovations designs and builds home additions across Chicago's North Shore and Lake County, including primary suites, kitchen and family room additions, and second-story additions. High-end additions here typically cost $400 to $700 or more per finished square foot, and most take 5 to 9 months to build after design and permits. We work with an architect and a structural engineer, and the owner runs every project.


Additions we build

  • Primary suite additions: a first- or second-floor bedroom, bath and closet suite.
  • Kitchen and family room additions: a rear addition or bump-out that turns a closed kitchen into the center of the house.
  • Second-story additions: adding a full floor, or a partial floor, over an existing ranch, split-level or one-and-a-half-story home.
  • Garage additions with living space above for an office, guest suite or in-law space.

What decides whether an addition works on your lot

On the North Shore, the lot and the rules set the limits. Before anyone draws, we check:


  • Zoning: setbacks, height limits, lot coverage and the municipality's cap on building size or floor area. Each town, including Lake Forest, Highland Park, Winnetka, Wilmette, Glencoe and Deerfield, calculates these differently.
  • Stormwater and grading: many towns require a grading or stormwater plan when an addition increases the hard surface on a lot.
  • Ravines and bluffs: lots on a ravine or lake bluff in Highland Park, Lake Forest and nearby towns have steep-slope rules that require geotechnical and engineering review.
  • Historic review: in Highland Park, most exterior changes to landmarks and contributing structures in historic districts need a Certificate of Appropriateness, and Lake Forest has its own local historic districts and review. We factor that time into the schedule.
  • HOA approval in subdivisions with an architectural committee.
  • Structure: a second story depends on whether the existing foundation and walls can carry the new load. A structural engineer confirms that early, before you spend on full drawings.

How the process works

  1. Feasibility walkthrough with Juan: goals, budget, lot and structure.
  2. Architect design and structural engineering, with our input on cost as the design develops, so there are no surprises at bid time.
  3. Fixed-scope proposal and permit submission, including any zoning, historic or HOA reviews.
  4. Construction in phases: foundation, framing, dry-in, mechanicals, then finishes. The tie-in to the existing house is where most of the craft is. We match brick, stone, siding, roofing and window profiles so the addition looks original.
  5. Final inspections, walkthrough and punch list.

What does a home addition cost?

Typical market ranges for high-end North Shore and Lake County additions in 2026, not a quote:


  • Finished addition space: about $400 to $700+ per square foot, depending on the foundation, finishes and how complex the tie-in is
  • Single-story family room, kitchen or primary suite addition (about 400 to 800 sq ft): about $250,000 to $600,000
  • Second-story addition: about $450,000 to $1,000,000 and up


Architect and engineering fees, and any interior remodeling around the addition, are usually on top of the construction cost.

How long does an addition take?

Typically 2 to 4 months for design and engineering, 1 to 3 months for permits and reviews, and 5 to 9 months of construction. Second-story additions often take 7 to 12 months to build. These are typical ranges, not a guaranteed schedule.

Frequently asked questions

  • How much does a home addition cost on the North Shore?

    Typical ranges in 2026, not a quote: about $400 to $700 or more per finished square foot. A 400 to 800 square foot single-story addition usually runs about $250,000 to $600,000, and a second-story addition about $450,000 to $1,000,000 or more. Design and engineering fees are usually extra.

  • How long does it take to build a home addition?

    Plan on about 2 to 4 months of design and engineering, 1 to 3 months of permits and reviews, and 5 to 9 months of construction for most additions. Second-story additions often take 7 to 12 months to build.

  • Do I need an architect for a home addition?

    Yes. North Shore and Lake County municipalities require stamped drawings for additions, and a structural engineer designs the foundation and framing. J & M Elite Renovations can build from your architect's plans or bring in an architect and engineer we work with.

  • Can my house support a second-story addition?

    Sometimes. It depends on the existing foundation, walls and framing, and on local height and building-size limits. A structural engineer evaluates the house early, and reinforcement or new footings are common before a second story goes on.

  • Can we live in the house while an addition is built?

    Often, yes, especially for single-story additions, because most work happens outside until the tie-in. Second-story additions usually require moving out for part of the project, since the roof comes off. We plan the phases with you.

  • Is it better to add on or move?

    If you like your town, school and lot, an addition often costs less than buying and remodeling another North Shore home once transaction costs are counted. It works best when zoning allows the space you need, which is the first thing J & M Elite Renovations checks.

Thinking about an addition?

Call Juan at (224) 480-3019 or request a consultation. We're available Monday to Friday 8 AM to 5 PM and Saturday 9 AM to 4 PM.