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Average Home Addition Costs in 2026
Home addition costs have stabilized since the post-pandemic spikes of 2021-2023, though labor shortages continue to drive prices upward in certain regions. Here is what homeowners are paying nationally in 2026.
The average home addition in the United States costs between $25,000 and $150,000, with most homeowners spending $55,000 to $95,000. On a per-square-foot basis, expect to pay $150 to $350 per square foot for a standard-quality addition with basic finishes, or $350 to $600+ per square foot for high-end construction in premium markets.
These numbers represent the full cost of a completed addition, including labor, materials, and basic interior finishing. However, they don't always include permits, architectural plans, utility connections, or landscaping restoration. When budgeting, plan to add 15-25% on top of the base construction cost for these additional expenses.
Where you live is the single biggest cost factor. A 400-square-foot bedroom addition that costs $48,000 in Mississippi could easily run $200,000 or more in California or Hawaii. That is a 4x difference for the same project, driven almost entirely by regional labor rates, material costs, and local building code requirements.
| Project Size | Low End | Average | High End |
|---|---|---|---|
| 200 sq ft (bump-out) | $16,000 | $40,000 | $100,000 |
| 400 sq ft (bedroom) | $32,000 | $80,000 | $200,000 |
| 600 sq ft (master suite) | $48,000 | $120,000 | $300,000 |
| 1,000 sq ft (second story) | $100,000 | $250,000 | $500,000+ |
Costs include labor, materials, and standard finishes. Does not include permits, design fees, or site preparation. Use our room cost calculator for a personalized estimate.
Cost by Addition Type
Not all home additions are created equal. A sunroom bump-out costs a fraction of a full second-story build. Here is how each type breaks down.
Bedroom Addition
$30,000 - $120,000200-400 sq ft | $100-$300/sq ft
A standard bedroom addition is one of the most common projects. It involves extending the foundation, framing walls, installing insulation, drywall, flooring, and basic electrical. Adding a closet is typical. Costs vary depending on whether you need to extend the roofline, add windows, or connect to existing HVAC. Ground-floor bedroom additions are simpler and more affordable than second-story bedrooms, which require structural reinforcement below. Use our room cost calculator to estimate your bedroom addition cost.
Bathroom Addition
$25,000 - $90,00050-150 sq ft | $200-$500/sq ft
Bathroom additions carry a higher per-square-foot cost than bedrooms because of the plumbing, waterproofing, and fixture requirements. A basic half-bath (toilet and sink) costs $10,000-$30,000, while a full bathroom with a shower or tub runs $25,000-$75,000. High-end master bathrooms with heated floors, walk-in showers, and double vanities can exceed $90,000. Plumbing proximity to existing supply lines is a major cost factor: bathrooms built directly above or adjacent to existing plumbing are significantly cheaper.
Kitchen Extension
$50,000 - $200,000+150-400 sq ft | $250-$500/sq ft
Kitchen extensions are among the most expensive home additions per square foot because they require plumbing, electrical, gas lines, ventilation, cabinetry, countertops, and appliance hookups. Expanding an existing kitchen by bumping out a wall is more affordable ($50,000-$100,000) than building a completely new kitchen space ($100,000-$200,000+). Costs escalate quickly with high-end appliances, custom cabinetry, stone countertops, and professional-grade fixtures.
Sunroom Addition
$22,000 - $75,000150-300 sq ft | $100-$350/sq ft
Sunrooms range from simple three-season screened enclosures to fully insulated, climate-controlled four-season rooms. Three-season sunrooms cost $22,000-$45,000 and are essentially enhanced porch structures with glass panels. Four-season sunrooms cost $40,000-$75,000+ because they require full insulation, HVAC extension, and proper foundation work to serve as year-round living space. Prefabricated sunroom kits can reduce costs by 20-30% compared to custom builds.
Second-Story Addition
$100,000 - $350,000+500-1,500 sq ft | $200-$500/sq ft
Adding a second story is the most complex and expensive type of home addition, but it doubles your living space without sacrificing yard area. The project typically involves removing the existing roof, reinforcing the foundation and first-floor walls to support the additional weight, building the new floor, framing, roofing, and installing a staircase. You will also need extended plumbing, electrical, and HVAC systems. The family must temporarily relocate during construction, which can take 5-7 months. Use our second story calculator for a detailed estimate.
ADU / In-Law Suite
$60,000 - $250,000+400-1,200 sq ft | $150-$400/sq ft
Accessory Dwelling Units (ADUs) are self-contained living spaces with their own kitchen, bathroom, and entrance. They have surged in popularity due to changing zoning laws, particularly in states like California, Oregon, and Washington that have relaxed ADU restrictions. Attached ADUs (built onto the existing home) cost $60,000-$150,000, while detached ADUs (separate structures) run $100,000-$250,000+. Many homeowners offset the cost by renting the ADU. Estimate your costs with our ADU calculator.
Garage Addition
$25,000 - $75,000200-600 sq ft | $50-$200/sq ft
A new attached garage is one of the more affordable additions because the finishing requirements are minimal: concrete slab, framing, roofing, a garage door, and basic electrical. Adding living space above the garage pushes costs to $75,000-$150,000 due to insulation, flooring, plumbing, and full interior finishing requirements. Detached garages cost slightly more due to separate foundation and utility runs.
Bump-Out Addition
$3,600 - $61,000Window-only to 120 sq ft | national averages
A bump-out extends an existing room by 2 to 10 feet outward. It is the smallest and most affordable type of home addition. Common uses include expanding a kitchen for an island, widening a bathroom, or creating a breakfast nook. Cantilevered bump-outs of about 2–3 feet don’t need a new foundation, which keeps them around $7,000–$17,000. Deeper bump-outs need footings, and kitchen or bath bump-outs that move plumbing can reach $60,000. See the full bump-out cost guide and estimator.
Where Your Money Goes: Cost Breakdown
Understanding how your budget is distributed helps you identify where to save and where not to cut corners. Here is the typical cost breakdown for a home addition project.
General contractor, subcontractors, skilled trades
Lumber, concrete, roofing, insulation, drywall, finishes
Building permits, architectural plans, engineering
Plumbing, electrical, HVAC extension, connections
Unexpected issues, change orders, price fluctuations
Labor is the largest expense and the one with the most regional variation. In metropolitan areas like New York City, San Francisco, and Boston, skilled tradespeople command premium rates. Union labor markets add additional cost. In rural areas and states like Mississippi, Alabama, and Arkansas, labor costs can be half of what coastal cities charge.
The contingency fund is not optional. Home additions frequently uncover hidden problems: termite damage, outdated wiring, foundation issues, asbestos in older homes, or soil conditions that require deeper footings. Experienced contractors recommend 10-20% contingency, with 15-20% for homes older than 30 years.
Factors That Affect Your Cost
Two identical 400-square-foot additions can cost wildly different amounts. These are the variables that determine where your project falls on the cost spectrum.
Geographic Location
The single biggest cost variable. Labor rates, material transportation costs, building code stringency, and market demand all differ by state. See our state-by-state cost guide below for specific pricing in your area.
Size & Complexity
Larger additions benefit from economies of scale (lower per-square-foot cost), but complex layouts with multiple corners, varying rooflines, or multi-level designs increase labor significantly. Simple rectangular additions are the most cost-effective.
Foundation Type
Slab-on-grade is cheapest ($5-$8/sq ft). Crawl space foundations add $7-$14/sq ft. Full basements cost $20-$35/sq ft but add usable space. Soil conditions, frost lines, and local codes determine which options are available.
Material Quality
Builder-grade materials cost 30-50% less than mid-range options. Premium materials (hardwood floors, quartz counters, custom cabinetry) can double or triple the finishing cost. Choose materials strategically based on where you spend the most time.
Plumbing & Electrical
Wet rooms (kitchens, bathrooms) cost 2-3x more per square foot than dry rooms (bedrooms, offices). The distance from existing plumbing and electrical panels matters: longer runs and panel upgrades add $3,000-$10,000+.
Timing & Season
Contractors charge premium rates during peak season (spring and summer). Starting in late fall or winter can save 5-15% in some markets. However, weather delays in cold-climate states may offset savings.
Home Addition Cost by State: State-by-State Guide
We have created detailed cost guides for 50 states with city-by-city pricing, local permit information, contractor tips, and regional factors. Click your state to see the full breakdown.
Regional Cost Breakdown
The United States can be divided into five broad pricing regions for home additions. Understanding these regional patterns helps you benchmark costs for your area.
Northeast
$165 - $420/sq ft average
The Northeast commands the highest home addition costs nationally, driven by dense urban development, aging housing stock, strict building codes, and strong union labor presence. Metro areas like New York City, Boston, and Philadelphia add substantial premiums. Older homes in this region frequently require additional structural work to integrate new additions with existing construction, adding 10-20% to project costs.
Southeast
$100 - $330/sq ft average
The Southeast offers the most affordable home addition costs in the country. Non-union labor markets, lower land values, simpler regulatory environments, and mild climate conditions (reducing weatherproofing requirements) all contribute to lower pricing. However, hurricane-prone coastal areas of Florida, the Carolinas, and Louisiana may require additional structural reinforcement and wind-rated materials that add 10-15% to costs. States like Mississippi and West Virginia offer the lowest prices nationally.
Midwest
$125 - $325/sq ft average
Midwest states offer solid value with moderate pricing. Cold-weather building requirements (deeper foundations below frost lines, enhanced insulation, snow load ratings) add some cost compared to southern states, but reasonable labor rates offset this. The Chicago metro area in Illinois and Minneapolis in Minnesota carry urban premiums, while states like Kansas, Iowa, and Nebraska provide some of the best value in the nation.
Southwest
$100 - $400/sq ft average
The Southwest shows wide variation. Oklahoma offers some of the lowest costs nationally at $100-$260/sq ft, while major Texas metros like Austin, Dallas, and Houston run $200-$400/sq ft due to rapid growth and high demand. Desert construction in Arizona and New Mexico requires specific materials for extreme heat, water management, and monsoon resistance. The region generally benefits from lower regulatory overhead and non-union labor markets.
West
$130 - $700/sq ft average
The West shows the widest cost range of any region. Hawaii leads the nation at $300-$700/sq ft because virtually all building materials must be shipped to the islands, and the limited contractor pool creates intense competition. California follows at $200-$600/sq ft, with the Bay Area and Los Angeles commanding the highest premiums. Washington and Oregon run $170-$450/sq ft, driven by Seattle and Portland's booming markets. Mountain states like Idaho, Montana, and Wyoming offer relative bargains at $130-$380/sq ft. Seismic requirements in earthquake-prone areas add structural costs.
Get Your Personalized Cost Estimate
Stop guessing. Use our free calculators built with 2026 pricing data to get an accurate estimate for your specific project.
Return on Investment (ROI)
One of the most common questions homeowners ask is whether a home addition will pay for itself. The answer is nuanced.
Home additions rarely return their full cost at resale. Nationally, mid-range additions tend to recoup roughly 40-80% depending on the type, quality, and local market conditions, and premium finishes recover about half as much. A midrange bathroom addition has an average ROI of about 53%, while functional additions like bedrooms in markets where homes typically have fewer bedrooms can perform better.
However, pure ROI does not tell the whole story. The financial case for a home addition should also consider what you would spend on alternatives: moving costs (typically $10,000-$30,000+), real estate commissions (5-6% of your home's sale price), higher mortgage rates on a new home, and the emotional cost of relocating your family. When you add it all up, building an addition is often the smarter financial move even at 50-60% resale ROI.
Projects with the highest ROI tend to be those that bring a home up to neighborhood standards. If every home on your street has three bedrooms and you have two, adding a third bedroom will likely recoup more of its cost. Conversely, over-improving beyond what the neighborhood supports yields diminishing returns. Use our ROI calculator to estimate the return on your specific project.
| Project Type | Avg Cost | Avg Value Added | ROI |
|---|---|---|---|
| Bathroom Addition (Midrange) | $60,000 | $32,000 | 53% |
| Bedroom Addition | $80,000 | $48,000 | 60% |
| Sunroom (Four-Season) | $55,000 | $30,000 | 55% |
| Master Suite | $130,000 | $78,000 | 60% |
| Second Story (Full) | $250,000 | $140,000 | 56% |
| ADU (Detached) | $175,000 | $105,000 | 60% |
ROI figures are national averages and vary by market. Hot real estate markets tend to see higher returns.
Permits and Building Codes
Building permits are required for virtually every home addition in the United States. Skipping them is not worth the risk.
Every home addition requires at minimum a general construction permit. Depending on your project scope, you may also need separate permits for electrical work, plumbing, HVAC installation, and demolition. Permit fees typically range from $500 to $5,000+, with some high-cost urban areas charging $5,000-$10,000 or more based on project valuation.
The permitting process involves submitting detailed construction plans, site plans, and engineering calculations to your local building department. Review times vary from 2 to 8 weeks depending on the jurisdiction and project complexity. Once approved, you will have scheduled inspections at key stages: foundation, framing, rough plumbing/electrical, insulation, and final inspection.
Building without permits is a serious mistake. The consequences include fines (often $500-$10,000+), mandatory demolition of unpermitted work, inability to sell your home (lenders require permit verification), insurance companies denying claims related to unpermitted construction, and personal liability if someone is injured due to substandard construction.
Zoning restrictions also affect what you can build. Setback requirements dictate how close your addition can be to property lines. Height restrictions may limit second-story additions. Lot coverage maximums cap the total building footprint relative to your lot size. If your planned addition violates zoning rules, you may need a variance, which requires a separate application and hearing process that can add weeks or months to your timeline.
For state-specific permit information, visit our detailed guides: California permits are among the most complex and expensive, while states like Texas and Florida have more streamlined processes in many jurisdictions. Check our complete permit guide for more details.
Project Timeline: What to Expect
From initial planning to move-in day, here is a realistic timeline for a typical home addition project.
Design & Planning (2-6 Weeks)
Hire an architect or designer, develop floor plans, select materials and finishes. For complex projects, structural engineering assessments are needed. This is the best time to get contractor quotes and finalize your budget.
Permitting (2-8 Weeks)
Submit plans to your local building department for review. Simple additions may be approved in 2-3 weeks. Complex projects in busy jurisdictions can take 6-8 weeks or longer. Your contractor can often handle permit applications on your behalf.
Site Prep & Foundation (1-3 Weeks)
Excavation, grading, utility marking, and pouring the foundation. Weather can affect this phase significantly. Foundation inspections must pass before framing begins.
Framing & Structural (2-4 Weeks)
Wall framing, roof framing, window and door installation, and sheathing. This is when the addition takes visible shape. Framing inspection is required before enclosing walls.
Rough-in & Systems (2-4 Weeks)
Electrical wiring, plumbing pipes, HVAC ductwork, insulation installation. Each trade requires separate inspections. Scheduling subcontractors is a common bottleneck at this stage.
Interior Finishing (3-6 Weeks)
Drywall, taping, painting, flooring, trim, cabinetry, countertops, fixtures, and appliances. This is the longest and most detail-intensive phase. Material lead times can cause delays if not ordered early.
Final Inspection & Completion (1-2 Weeks)
Final building inspection, punch list items, exterior finishing, landscaping restoration, and cleanup. Once you pass final inspection, you receive your certificate of occupancy and the addition is officially livable.
Total timeline: 3-7 months from permit approval to completion. Add 1-2 months for design and permitting. Second-story additions and complex projects skew toward the longer end. Weather delays, inspection backlogs, and material shortages can extend any phase.
12 Ways to Save on Your Home Addition
Smart planning can reduce your home addition cost by 15-30% without sacrificing quality. Here are proven strategies.
Get 3-5 Contractor Quotes
Quotes for the same project can vary by 30-50%. Get at least three detailed, itemized bids. Compare scope, materials, and timeline, not just total price.
Build During Off-Season
Late fall and winter projects (in mild climates) can save 5-15% as contractors offer lower rates to keep crews busy during slower periods.
Keep the Design Simple
Rectangular additions with standard rooflines cost significantly less than complex shapes. Every corner, angle, and custom detail adds labor cost.
Choose Standard Materials
Builder-grade or mid-range materials cost 30-50% less than premium options. Upgrade selectively in high-visibility areas and save on hidden components.
Minimize Plumbing Runs
Place new bathrooms and kitchens adjacent to or above existing plumbing. Long plumbing runs add thousands in material and labor costs.
Consider a Bump-Out First
Before committing to a full addition, see if a 4-8 foot bump-out can solve your space problem. They cost a fraction of a full room addition.
Finalize Plans Before Starting
Change orders during construction are expensive. Every mid-project modification adds 15-25% to the cost of that specific element. Lock in your design before breaking ground.
Do Some Work Yourself
Painting, landscaping, demolition, and cleanup are tasks many homeowners can handle. This can save $5,000-$15,000. Leave structural, electrical, and plumbing work to licensed professionals.
Reuse Existing Structure
Converting existing space (garage, attic, basement) is much cheaper than building new. Conversions typically cost 40-60% less than new construction of equivalent size.
Order Materials Early
Long lead-time items (windows, doors, cabinetry) should be ordered weeks before they are needed. Rush orders and expedited shipping add significant cost.
Check for Tax Credits
Energy-efficient additions may qualify for federal or state tax credits. High-efficiency HVAC, insulation, windows, and solar panels can offset costs through incentive programs.
Negotiate Payment Terms
Never pay more than 10-15% upfront. Structure payments around milestones. Hold 10% for final completion and punch list items. This protects your investment and keeps the project moving.
Common Mistakes to Avoid
These are the pitfalls that derail budgets, timelines, and satisfaction. Learning from others' mistakes can save you thousands.
Underestimating the Budget
The most common mistake is budgeting only for construction costs and forgetting permits ($500-$5,000), design fees ($2,000-$10,000), utility connections ($1,000-$5,000), landscaping restoration ($1,000-$5,000), temporary living costs, and contingency (10-20%). A project quoted at $80,000 will likely have a true all-in cost of $95,000-$110,000.
Hiring the Cheapest Contractor
The lowest bid is often lowest for a reason: cutting corners on materials, using inexperienced labor, or underestimating the scope. A cheaper contractor who delivers poor quality or abandons the project mid-way will ultimately cost more. Check references, verify licenses and insurance, and look for contractors who have completed similar projects in your area.
Making Changes During Construction
Change orders are project killers. Moving a wall 2 feet, changing the window size, or upgrading materials mid-project typically costs 25-50% more than it would have if planned from the start. Spend extra time in the design phase and commit to your plans before construction begins.
Ignoring the Addition's Impact on Existing Space
An addition affects your home's flow, natural light, HVAC balance, and curb appeal. Poorly designed additions block windows, create awkward transitions, overburden heating/cooling systems, or look like obvious afterthoughts from the street. Good design integrates the addition seamlessly with your existing home.
Skipping Permits
Building without permits to save money almost always backfires. When you sell your home, unpermitted additions are discovered during inspections. You will either need to demolish the work, pay to bring it up to code and retroactively permit it, or accept a significantly lower sale price. Insurance companies may also deny claims related to unpermitted construction.
How to Finance a Home Addition
Most homeowners do not pay for a home addition entirely in cash. Here are the most common financing options and when each makes sense.
Home Equity Loan (HEL)
A lump-sum loan using your home equity as collateral. Fixed interest rate and predictable monthly payments. Best for homeowners who know their exact project cost and prefer certainty. Interest may be tax-deductible if the loan is used to improve your home.
Best for: Well-defined projects with a firm budget | Typical rates: 7-10% (2026)
Home Equity Line of Credit (HELOC)
A revolving credit line that lets you draw funds as needed. Variable interest rate. Ideal for projects with uncertain final costs or phased construction. You only pay interest on what you draw, making it flexible for managing contractor payments.
Best for: Phased projects or uncertain budgets | Typical rates: 7-11% variable (2026)
Cash-Out Refinance
Replace your current mortgage with a larger one and receive the difference in cash. This can make sense if current mortgage rates are similar to or lower than your existing rate. Not ideal if it significantly increases your rate or extends your loan term.
Best for: Homeowners who can maintain or improve their rate | Typical rates: 6.5-8% (2026)
Construction Loan
Short-term financing specifically for construction projects. Funds are disbursed in stages as construction milestones are met. Converts to a permanent mortgage upon completion. Higher rates but designed for large projects where the added home value will support refinancing.
Best for: Large additions ($100K+) with clear value add | Typical rates: 8-12% during construction
Personal Loan
Unsecured loan that does not require your home as collateral. Faster approval process but higher interest rates and lower limits. Best for smaller additions or bump-outs under $50,000 where the speed and simplicity outweigh the rate premium.
Best for: Smaller projects under $50K | Typical rates: 8-15% (2026)
Is a Home Addition Worth It?
The decision to build a home addition involves financial, practical, and emotional factors. Here is how to evaluate whether it is the right choice for you.
A home addition makes financial sense when the cost of building is less than the cost of moving to a comparable larger home in your area, when the addition brings your home up to neighborhood standards (a missing bedroom or bathroom), when you plan to stay in the home long enough to enjoy the improvement (typically 5+ years), or when the addition generates income (ADU rental, home office that eliminates a commute).
A home addition may not make sense when it would over-improve your home beyond what the neighborhood supports, when the cost exceeds 50% of your current home value in a flat or declining market, when your home has fundamental issues (bad foundation, poor location, outdated systems) that the addition does not address, or when you are planning to sell within 2-3 years and unlikely to recoup the investment.
The "move vs. improve" calculation often favors building. Consider: real estate agent commissions on selling your current home (5-6% of sale price), moving costs ($10,000-$30,000), closing costs on a new home (2-5%), potentially higher mortgage rates, the disruption of changing schools, commutes, and community ties, and the time and stress of house hunting. For a homeowner in a $400,000 home, selling and buying equivalent could cost $40,000-$60,000 in transaction costs alone, before any premium for additional space.
Ultimately, many homeowners find that the non-financial benefits, staying in a neighborhood they love, keeping their children in the same schools, customizing the space to their exact needs, are the most compelling reasons to build rather than buy.
Free Home Addition Calculators
Ready to estimate your project? Our calculators use 2026 pricing data to give you accurate, location-adjusted cost estimates.
Room Cost Calculator
Estimate costs for bedrooms, bathrooms, kitchens, and more by size and location.
Second Story Calculator
Get detailed estimates for adding a full or partial second story to your home.
ADU Calculator
Plan your accessory dwelling unit with pricing for attached and detached units.
ROI Calculator
Calculate the return on investment for your home addition project.
Frequently Asked Questions
Quick answers to the most common questions about home addition costs.
How much does a home addition cost per square foot?
The national average is $150-$350 per square foot for a standard-quality addition. Ground-floor additions cost $80-$200/sqft, second-story additions $200-$500/sqft, and premium finishes can push costs above $500/sqft. Prices vary significantly by state. Check your state's specific cost guide for local pricing.
What is the cheapest type of home addition?
Bump-outs are the most affordable: a box or bay window bump-out starts around $4,000, and a small cantilevered bump-out that adds floor space runs about $7,000-$17,000. Sunroom additions ($22,000-$45,000 for three-season) and garage additions ($25,000-$50,000) are also relatively affordable. Converting existing space (basement, attic, garage) is typically cheaper than building new square footage.
How long does a home addition take to build?
Most home additions take 3-7 months from permit approval to completion. A simple bump-out takes 4-8 weeks, a standard room addition 3-5 months, and a full second story 5-7 months. Add 1-2 months for design and permitting before construction starts.
Do home additions increase property value?
Yes, home additions typically increase property value, but they rarely recoup 100% of their cost. Nationally, mid-range additions recover roughly 40-80% depending on type (garage conversions at the top, second stories at the bottom), and premium finishes recover about half as much. Additions that bring a home up to neighborhood standards (adding a missing bedroom or bathroom) tend to have the best returns. Over-improving beyond the neighborhood can yield diminishing returns. Use our ROI calculator to estimate your return.
Is it cheaper to build an addition or move to a bigger house?
In many cases, building an addition is cheaper than moving when you factor in real estate commissions (5-6%), closing costs (2-5%), moving expenses ($10,000-$30,000), potentially higher mortgage rates, and the intangible costs of relocating. However, if your home needs major structural work or is in a declining market, moving may be the better financial choice.
What permits do I need for a home addition?
At minimum, you need a general construction permit. Most additions also require separate electrical, plumbing, and HVAC permits. Permit costs range from $500-$5,000+ depending on location and project size. Your general contractor can usually handle the permit application process. See our permit guide for details.
Should I get a home equity loan to pay for an addition?
A home equity loan is one of the most popular options because it offers lower interest rates than personal loans and the interest may be tax-deductible. However, your home serves as collateral, so there is risk if you cannot make payments. A HELOC provides more flexibility for projects with uncertain budgets. Compare options based on your financial situation, project size, and risk tolerance.
How much contingency budget should I set aside?
Plan for a 10-20% contingency fund. Newer homes (built after 2000) can lean toward 10%. Older homes should budget 15-20% because hidden issues like outdated wiring, asbestos, termite damage, or foundation problems are more common. A $100,000 project should reserve $10,000-$20,000 for unexpected costs.
Ready to Plan Your Home Addition?
Start with your state's detailed cost guide for local pricing, permit info, and contractor tips. Then use our free calculators to build your budget.