If you are like many homeowners, the cost estimate for a kitchen expansion will impact your kitchen remodel design. Such an estimate aids in setting your budget and will help you make choices in design and features so that you remain within that budget. You can use it to make priority decisions about the features you want and the work you wish to include. You’ll know what do at present and what must be postponed.

In a kitchen expansion, construction costs are a primary factor so you’ll need to calculate that cost before you get far into the project. When you have this particular estimate, you’ll know whether or not you’ll want to remodel the kitchen along with the expansion, or if you’ll just want to go ahead with the expansion for now.

The features in the cost for construction include:

  • Putting in the foundation. Do you know if your expansion will be so large as to require a foundation? What about using posts for the expansion instead of a foundation? Your expansion may be small enough that a bump-out will be all that you will need.
  • Providing a seamless addition to the existing roof. Of course, you will want a roof for your expansion. You will wish to create a new roof that is seamless with your existing roof. It is the best way to provide proper drainage from the roof and will look nice, too.
  • Insulation and framing issues. Consider the cost of insulating exterior walls and framing the expansion.
  • External Siding. Plan for the exterior walls and determine if they are to be wood, masonry  or another type of siding. The materials you choose should blend with or match the siding you already have.

You need to consider the following aspects that will impact your overall cost of expansion:

  • What about a fireplace?
  • Do you require new windows or doors?
  • Does your expansion include a pantry?
  • What about a skylight?
  • Do you need new plumbing or for the existing plumbing to be  moved?
  • Will you require the addition of new gas lines?

Preliminary construction costs estimates can be calculated on a cost-per-square-foot basis. You can get the average cost-per-square-foot for an addition in your location from several sources, including local contractors and your local government.  Click here to get a contractor referral.


The information you will need to provide to get this estimate includes the following:

  • How much of the work will you do yourself?
  • What level of quality do you want in the job – economy, average, custom?
  • What is the size in square feet of your existing kitchen?
  • What will be the size in square feet of the extended kitchen?

Much of this process involves going back and forth between your wish list, your budget, and the estimate you’re working off of. You may decide that doing some of the work yourself will help you save money on the project. Or it may turn out to be cheaper to do the expansion and the remodel in two separate phases.

When you plan your kitchen expansion or addition, it becomes easier when you have a reliable construction cost estimate.  Click here to use our kitchen remodeling calculator.