Professional Home Additions in Northern Illinois and Southern Wisconsin
Outgrowing your home in the Stateline area doesn’t have to mean you have to move. A well-planned home addition can give you the extra space you need while keeping you in the neighborhood you already love.
ERS Builders is a trusted home addition contractor serving Rockford, Roscoe, Rockton, Beloit, Janesville, and the surrounding communities. We design and build additions that look and feel like part of your current home. From planning and permits to final finishes, we manage every step, so you can expand your home without unnecessary stress.
- 25+ Years of Experience
- Serving Winnebago County, IL & Rock County, WI
- Fully Managed Design-Build Process
Types of Additions We Build
Every home addition project is unique. As experienced room addition contractors in Rockford, IL and throughout Northern Illinois and Southern Wisconsin, we build practical spaces that improve how your home functions day to day.
We specialize in additions of all types, including:
- Room Additions – Add a new bedroom, family room, or office to create more usable living space without changing your home’s overall layout.
- Kitchen Expansions – Open up tight kitchens or add square footage for better flow, storage, and gathering space.
- Bathroom Additions – Reduce congestion in busy households by adding a full or half bathroom where it makes the most sense.
- Second-Story Additions – Maximize your square footage without expanding your footprint by building upward—ideal for homes with limited lot space in Winnebago County and Rock County.
- In-Law Suites & Guest Spaces – Create comfortable, private areas for extended family or long-term guests.
Home Addition Contractors Serving Rockford, Roscoe, Rockton, Beloit, & Janesville
ERS Builders proudly provides home additions throughout the Stateline area. Our local experience allows us to design additions that meet zoning requirements while matching the style and structure of homes in each community.
We serve homeowners across Southern Wisconsin and Northern Illinois, including:
- Rockford, IL
- Roscoe, IL
- Rockton, IL
- South Beloit, IL
- Beloit, WI
- Janesville, WI
Navigating Permits and Codes for Additions in the Stateline Area
Building a home addition in Northern Illinois or Southern Wisconsin requires careful planning and compliance with local regulations. We manage all local filings in Rockford, Janesville, South Beloit, and the surrounding communities, so you don’t have to.
Our familiarity with local building departments helps prevent delays, reduce unexpected issues, and keep your project on schedule. We handle the entire process, including:
- Local zoning and setback requirements
- Permit applications in Winnebago County and Rock County
- Inspections and code compliance
- Coordination with city and municipal offices
Why Homeowners Choose ERS Builders for Home Additions
A home addition is a major investment, and choosing the right contractor matters. ERS Builders combines design expertise, construction experience, and local knowledge to deliver high-quality results.
- 25+ years of hands-on construction experience
- Licensed and insured in Illinois and Wisconsin
- Extensive knowledge of Illinois and Wisconsin building codes
- Design-build approach for better efficiency and communication
- Focus on structural integrity, durability, and seamless design integration
Our Design-Build Process for Home Additions
Our design-build approach keeps everything aligned from the first conversation through final construction.
Concept & Design
We start by understanding how you want to use the new space. From there, we design an addition that connects naturally to your existing home, so your addition feels intentional, not like an afterthought.
That includes:
- Matching rooflines, siding, and structural elements
- Aligning floor levels and transitions
- Planning layouts that improve flow and usability
Transparent Budgeting
Unexpected costs are one of the biggest concerns homeowners have with construction. We address that upfront with clear, detailed proposals.
You’ll know:
- What’s included in the scope of work
- Material and construction expectations
- A realistic budget and timeline
Expert Construction
Once construction begins, we focus on efficiency and minimizing disruption to your daily life by:
- Keeping job sites clean, organized, and safe
- Coordinating with trusted local trade partners
- Providing clear communication throughout the project
Frequently Asked Questions
Will a home addition increase my property taxes in Illinois or Wisconsin?
Yes, in most cases. Adding square footage or upgrading your home typically increases its assessed value. The exact impact depends on your local municipality in Winnebago County or Rock County. We can help you understand what to expect based on your location.
How much does a home addition cost in Northern Illinois or Southern Wisconsin?
The cost of a home addition in Rockford, South Beloit, or the surrounding area depends on several factors, including the size of the space, type of addition, materials, and structural complexity. For example, a simple room addition will cost less than a second-story build or a kitchen expansion with plumbing and electrical work.
After an on-site evaluation, we provide a detailed estimate so you know exactly what to expect before construction begins.
How much square footage can I add to my lot?
This depends on local zoning regulations, setback requirements, and lot coverage limits. These rules vary between Winnebago County and Rock County. We review your property and confirm what’s allowed before design begins.
How long does a typical room addition take?
Timelines vary based on size and complexity. Smaller additions may take several weeks, while larger or multi-phase projects can take a few months. We provide a clear schedule during the planning phase so you know what to expect.
Ready to Start Your Home Addition?
If your current home no longer fits your needs, a custom home addition can give you the extra square footage you’re missing without the hassle of moving. ERS Builders provides practical, well-constructed home additions that improve comfort, function, and long-term value.
Schedule your free estimate today to start planning your project with a trusted local builder.
We build high-quality home additions for homeowners throughout Winnebago County, Illinois and Rock County, Wisconsin, including in Rockford, Roscoe, Rockton, Beloit, and Janesville.
Why Homeowners in Northern Illinois and Southern Wisconsin Choose ERS Builders
Licensed ● Insured ● Locally Owned ● 25+ Years of Hands-On Experience
We focus on doing the job right and making sure every decision makes sense for your home and budget.
- \Experienced Leadership on Every Job: Co-owner Eric Schnack brings more than two decades of building experience and stays closely involved from start to finish.
- \Local and Relationship-Driven: ERS Builders is locally owned and proud to consistently earn new business from repeat clients and referrals within the community.
- \Broad Residential Expertise: From basement finishes and home additions to roofing and full restorations, we handle a wide range of residential construction needs.
- \One Clear Point of Contact: We manage permits, scheduling, and trusted trade partners so you’re not juggling multiple contractors.
- \Planning That Starts With You: We listen first, discuss options, and help you choose an approach that fits your goals and investment level.
- \Projects Sized to Fit Your Needs: Our team is comfortable handling everything from smaller, single room remodels to larger-scale interior expansions.
Additional Contracting Services in Northern Illinois & Southern Wisconsin
Many homeowners choose to combine their addition with other upgrades. ERS Builders offers a full range of remodeling and outdoor living services to complement your home addition, including:
Interior remodeling
Bathroom Remodeling: Transform your bathroom with better layouts, modern fixtures, and better storage.
Kitchen Remodeling: Remodel your kitchen with updated cabinetry, lighting, flow, and finishes.
Basement Remodeling: Finish your basement into a livable space like a family room, office, or guest space—built safely to code.
Exterior home renovations
When your home needs more space, an addition can be a smart alternative to moving. ERS Builders constructs interior additions that integrate smoothly with the existing structure. From planning and permitting to framing and finishing, we create additions that look intentional, function well, and add long-term value.
Custom decks and patios
Expand your living space outdoors with a custom deck or patio. We design and build outdoor spaces that fit your yard, lifestyle, and maintenance preferences. Whether you want a simple deck or a larger entertaining area, ERS Builders focuses on solid construction and durable materials.
Roofing repair and replacement
ERS Builders offers residential roofing services that prioritize durability, expert installation, and long-term performance, so you can rest assured that your home is protected from Midwest weather. We handle roof replacements and repairs using quality materials and proven methods. Our team evaluates the condition of your roof, explains your options clearly, and completes the work with attention to detail and safety.