Thinking about adding extra space to your home? A house extension could be the perfect solution—but how much does it really cost? Let’s break it down.

Ever stood in your living room and thought, “We need more space”? You’re not alone. I felt the same pinch when my second child was on the way. Suddenly, our cozy home felt like it was shrinking by the day.

A house extension might be your answer – but that nagging question remains: what’s this going to cost me? Let’s cut through the confusion and get you some real numbers.

Why Homeowners Are Choosing House Extensions

The math is simple: moving costs a fortune. Between realtor fees, closing costs, and the emotional toll of leaving a neighborhood you love, staying put often makes more sense.

House extensions give you the best of both worlds – you keep your address while creating the extra space your family craves. Plus, you’re not just spending money; you’re investing it. A well-designed extension typically returns 70-80% of its cost in added property value.

One Columbus homeowner told me, “We considered moving to the suburbs for more space, but after pricing an extension, we realized we could get exactly what we wanted without uprooting our kids from their schools.” Their kitchen expansion cost less than half what they would have spent on moving expenses alone.

But let’s talk dollars and cents – what should you expect to pay?

Factors That Influence House Extension Costs

No two extensions cost the same. Your final price tag depends on several key factors:

Size and Scope: This one’s obvious – bigger costs more. In Columbus, you’re looking at roughly $150-$300 per square foot for basic extensions. A simple 300 sq ft single-story addition starts around $45,000, while larger projects can easily exceed $100,000.

Design Complexity: Straight walls and standard windows cost less than curved walls and custom features. A basic rectangular extension might run 30% less than one with complex rooflines or architectural details.

Materials: The difference between standard and premium materials can double your costs. Here’s a quick breakdown of material costs for a mid-range 300 sq ft extension in the Columbus area:

• Foundation work: $10,000-$15,000
• Framing: $15,000-$20,000
• Exterior finishing: $8,000-$20,000 (vinyl siding vs. brick can triple this cost)
• Roofing: $5,000-$12,000
• Windows and doors: $5,000-$15,000

Labor and Permits: Local labor rates in Columbus typically run $50-$100 per hour for skilled contractors. Permit costs vary by township but expect to pay $500-$2,000 depending on your project’s scope.

The Ohio climate adds another consideration: proper insulation. Our hot summers and freezing winters mean cutting corners on climate control will cost you more long-term than doing it right the first time.

Types of House Extensions and Their Costs

Let’s break down some common extension types and their typical Columbus price ranges:

Single-Story Extensions: These are often the most popular for expanding kitchens, living rooms, or adding a home office. Cost-effective compared to double-story, but still requires careful planning. For a quality build with mid-range finishes, budget $150-$250 per square foot. A 300 sq ft addition would cost $45,000-$75,000.

Double-Story Extensions: A bigger investment, but they maximize your square footage and can dramatically increase your home’s value. Think adding a master suite and a family room. While they cost more upfront ($250-$350 per square foot), you’re essentially getting two floors for one foundation. A 600 sq ft two-story addition (300 sq ft per floor) typically runs $150,000-$210,000 in the Columbus market.

Garage Conversions: A smart way to utilize existing space, often turning a dusty garage into a functional living area. Can be a budget-friendly option. The budget-friendly option, typically costing $20,000-$50,000 depending on finishes. Since the structure already exists, you’re mainly paying for interior work. Just remember: you’re also losing parking space and storage.

Basement Renovations: Common in Ohio, basements offer huge potential for extra living space. However, waterproofing and moisture control are critical and can add to the cost. Expect to pay $35-$75 per square foot, with waterproofing being critical given our region’s moisture issues. A full basement renovation can range from $30,000-$75,000 depending on square footage and finishes.

Hidden Costs to Watch Out For

This is where many homeowners get tripped up. It’s not just about the visible stuff. Watch out for:

• Foundation Surprises: Unexpected issues with your foundation (soil conditions, structural problems) can lead to significant cost overruns.
• Utility Upgrades: Moving plumbing, electrical, or HVAC systems can be a major expense.
• The “Finishing Line” Effect: Flooring, paint, lighting, fixtures – these “small” details add up quickly.

Tips for Budgeting Your House Extension

After talking with dozens of Columbus homeowners who’ve completed extensions, here’s what the successful ones did differently:

Start with a realistic contingency fund. The pros recommend setting aside 15-20% of your total budget for unexpected costs. If you don’t need it, great – upgrade your finishes or take a vacation to celebrate. This isn’t just about foundation surprises – it covers everything from weather delays to material price increases that happen mid-project. 

Phase your project if needed. One Dublin family completed their extension in three annual phases, allowing them to spread costs while still achieving their dream home. Their approach was genius: they started with the shell extension (foundation, framing, roofing, windows) in year one, finished the interior in year two, and added custom features and landscaping in year three. This strategy gave them breathing room financially while allowing them to adjust plans as their needs evolved. 

Prioritize based on ROI. Some investments pay back better than others. In Columbus, kitchens and primary bedroom extensions typically return 70-80% of their cost in added value, while specialized rooms like home theaters return less than 50%. Smart Columbus homeowners use this equation: Cost of feature – Value added = True cost. For example, upgrading to energy-efficient windows might cost $3,000 more upfront but save $200 annually in energy costs and add $2,000 to home value. With a true cost of only $1,000 spread over decades, that’s a no-brainer. Meanwhile, that custom wine cellar might cost $15,000 but only add $5,000 to home value – a true cost of $10,000 that only makes sense if you’re a serious collector who will enjoy it for many years.

Get multiple bids. Prices can vary by 20-30% between contractors for the same work. Three estimates is the minimum to ensure you’re getting fair pricing. But don’t just look at the bottom line – analyze what’s included in each bid. Some contractors include allowances for fixtures and finishes that may not match your expectations. Others might exclude important items like permits or debris removal. Create a standardized comparison sheet listing every component of the project, and make sure each contractor addresses each item. 

Consider timing. Winter construction can sometimes save 5-10% as contractors compete for fewer available projects during the off-season. January through March is typically the sweet spot in Columbus for negotiating better rates. However, weather considerations make this approach better suited for interior work like basement renovations rather than projects requiring extensive excavation. 

Ready to Expand Your Home? Let’s Talk Costs

The bottom line: for a quality house extension in Columbus, expect to budget:

• $45,000-$75,000 for a modest single-story addition
• $150,000-$210,000 for a double-story extension
• $20,000-$50,000 for a garage conversion
• $30,000-$75,000 for a basement renovation

These figures assume mid-range finishes and standard designs. Custom or luxury features will push these numbers higher.

Remember, the cheapest bid rarely delivers the best value. Quality construction pays dividends through lower maintenance costs, better energy efficiency, and higher resale value.

If you’re serious about extending your home in Columbus, DC Homes specializes in transparent, fixed-price extension projects. Contact DC Homes today for a free, no-obligation consultation and detailed estimate tailored to your specific extension project.