What to Know Before Designing Your Custom Home in Washington State

Introduction

Designing a custom home is a deeply personal journey and one of the most significant investments many people will ever make. While it’s exciting to envision your ideal layout, finishes, and style, a successful custom home requires more than inspiration—it requires informed planning, collaboration, and a clear understanding of the local regulatory landscape. At Harmony Space Architecture, we’ve guided many homeowners in Washington State through this process, from concept to construction. This guide outlines the key considerations to help you get started with confidence.

1. Understand Your Site and Zoning

Before hiring a contractor or dreaming up design features, it’s critical to understand what’s possible on your property. Zoning codes dictate how large your home can be, how far it must be set back from property lines, how tall it can be, and more.

• Key Tip: Request a zoning summary or hire an architect to perform a zoning analysis before designing anything.

• Bonus: Sites with steep slopes, wetlands, or other environmentally critical areas may have additional restrictions.

2. Define Your Budget Early

A common challenge in custom home design is misalignment between vision and budget. Costs can vary widely based on location, materials, labor, and design complexity.

• Soft Costs: These include architectural fees, engineering, permit fees, and surveys.

• Hard Costs: These cover construction, site preparation, utilities, and finishes.

Tip: Be realistic and include a 10–15% contingency for unexpected costs. Your architect can help you align your design to your financial goals.

3. Choose the Right Architect

The right architect does more than draw plans—they become your trusted guide through zoning, permitting, and design decisions. Look for someone who:

• Understands your goals and style

• Has experience with projects in your area

• Offers end-to-end service, including permit drawings and construction oversight

At Harmony Space Architecture, we specialize in designing homes that are not only beautiful and functional but also thoughtfully integrated with Washington’s regulatory environment.

4. Choose the Right Architect Compact, Efficient Housing

With rising land and construction costs, many homeowners and developers are shifting toward smaller, smarter homes. But small doesn't mean sacrificing comfort or style.

• Townhouses, cottage clusters, and duplexes are becoming more common

• Design strategies like built-in storage, open sightlines, and vertical expansion help make compact spaces feel generous

• Unit Lot Subdivision allows developers to build multiple fee-simple homes on a single parcel—ideal for infill and missing-middle housing

At Harmony Space, we’re passionate about designing efficient housing that supports density, livability, and environmental sustainability.

5. Consider Sustainability and Energy Efficiency

Washington has robust energy codes, and many homeowners today are prioritizing sustainability. A well-designed custom home can reduce long-term costs and environmental impact.

Some ideas to explore:

• Passive solar orientation

• High-efficiency insulation and windows

• Green roofs or rainwater harvesting

• All-electric or hybrid heating systems

Many of these features can also help you qualify for tax incentives or green certifications.

6. Prepare for the Permit Process

Permitting in Washington can be complex and varies by city or county. Most custom homes require architectural drawings, site plans, and reports by structural engineers or other specialists. Your architect will manage this process and coordinate with reviewers to secure approvals.

Typical documents for submittal include:

• Site plan

• Floor plans and elevations

• Structural drawings

• Energy code compliance forms

7. Think Beyond Design - Plan for Construction

Your project isn’t done when the plans are approved. You’ll need to select a builder, finalize a construction contract, and manage your timeline and payments.

Some architects (like us) offer design-build coordination or can recommend trusted contractors. Communication, coordination, and supervision during construction are essential to keeping your vision on track.

8. Conclusion

A custom home is your chance to create a space that reflects your lifestyle, values, and aspirations—but it starts with smart planning and the right professional guidance. At Harmony Space Architecture, we’re here to help you translate your ideas into a design that’s practical, code-compliant, and inspiring. If you're ready to begin your custom home journey in Washington State, let’s start the conversation.