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Q. What do I need to know about building an addition onto my home?

A: Many homeowners love their neighborhood and their home, and they have no desire to move.

But due to changes in the size of their family, they really need more space. An addition can provide extra living space and add resale value to your home.

When an addition is built on a home, it changes what is called the “footprint.” And any time you change the footprint of a home, you will need building permits from your local city or county in order to have a legal project.

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This is critical — if city or county regulations are not followed, there can be costly penalties and you could be required to have the work redone or in some cases removed.

A qualified remodeling contractor or design professional can help you determine what work is needed, create a realistic budget for the project, and create a schedule of construction that includes a detailed scope of work. Your contractor will also help facilitate the permitting process.

Washington state does not require that you hire a professional architect to craft plans for a remodel, but it’s a good idea to have plans professionally analyzed for feasibility before submitting them for permitting.

When you are thinking about a budget for your home addition, be aware that your project might require the services of an architect. If so, those fees could amount to 15 percent of your total construction costs. Some construction companies have design capabilities.

These design-build firms fold the architectural fees into the construction budget, often at a discount because you’re hiring them for the entire process. Another potential expense could be engineering services. Your local building authority might require that a soils engineer evaluate a steeply sloped yard, for example.

Other expenses to plan for when building an addition include increased insurance premiums and higher property taxes, which go hand-in-hand with the increased value of your home.

Don’t forget about the likelihood of landscaping repair. Some of your new space may replace turf, shrubs, flower beds or even trees. And even though the contractor’s crew is careful, the daily construction process — from heavy foot traffic to possible heavy machinery and staging materials — could take a toll on remaining vegetation.

Every home addition is unique, so as you begin the process, it’s a good idea to budget for a few unexpected expenses along the way.

Before settling on a price for the addition work, make sure your agreement includes what is called a change-order policy.

The change order spells out costs for any alterations that you may want after the contract is signed. This protects both you and your contractor. You will have a clear idea of what costs you could incur if you change your mind about what you want done or the materials you want to use after the contract is signed.

Every remodel includes the unexpected, from products suddenly on back order to weather delays. Knowing what to expect can help your family survive the process and thrive in your new space.

Jon W. Simpson, owner of JWS Design, Inc., is a member of the Master Builders Association of King and Snohomish Counties’ Remodelers Council and provided the information contained in this article. If you would like more information or have questions about home improvement send them to

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