Is It Cheaper to Add On to Our House or Move to a Bigger One?
It depends on your finances, timing, and what you want from the home. This comparison depends heavily on the scope of the addition and local construction costs, which vary significantly by region and project complexity.
Typical addition costs
A modest addition, such as converting a garage into a bedroom or playroom, often runs $20,000-50,000. A full room addition with new foundation work typically costs $100-300 per square foot, and a second-story addition, given the structural engineering involved, can run $150,000-300,000 or more depending on size and finishes.
When moving is the cheaper option
If an addition would cost more than roughly 10-15% of the home's current value, moving to a larger home often becomes the more cost-effective path, particularly when factoring in the temporary disruption and potential permit delays that come with major construction.
Hidden costs on both sides
Moving involves real estate agent commissions (commonly 5-6% of the sale price), closing costs on the new purchase, and moving expenses. Adding on involves permit fees, potential temporary housing during construction, and the risk of unexpected costs once walls are opened up and existing conditions are discovered.
How financing an addition typically works
Most families finance a significant addition through a home equity loan, HELOC, or a cash-out refinance, rather than paying entirely out of pocket. Each option carries different rates and repayment structures, and comparing them against a mortgage on a larger replacement home is worth doing with an actual lender rather than assuming the addition is automatically the cheaper financed option.