Seattle's Trusted Second Story Addition Experts

Expanding up isn’t just about adding space—it’s about reimaging structure, flow, and comfort. Let’s explore the possibilities together. Contact us for a free consultation today!

Experience

Over 20 years of experience shaping solutions that balance aesthetics and function.

Design

Focused on creating healthy, sustainable spaces that respond to light, air, and context.

Expertise

Expert in codes, zoning, and permits across more than 22 jurisdictions in Washington State.

Support

Support from the first meeting through design, permitting, and construction coordination

Featured second story additions

Why second story additions are complex

A second story addition can dramatically improve your home’s function and appearance. However, these projects rank among the most complex in residential construction, requiring structural reinforcements, strategic layout adjustments, and coordination across HVAC, plumbing, and electrical—all while integrating with the home’s existing conditions.

Dormer addition - Ballard Seattle Sugi Ban

Need more space?

Sometimes building up is the only option.

When lot size is limited or zoning restricts expansions, a second story gives you a way to grow without sacrificing your yard. It’s ideal for homeowners who want more square footage and better views—without leaving their neighborhood.
Second story addition - West Seattle Puget Perch

Structure Comes First

Your foundation needs to be ready to carry the weight.

Adding an upper floor increases the structural load on your home, so a licensed structural engineer must assess the existing foundation and framing before construction begins. In many cases, upgrades such as seismic upgrades or adding new footings are required to ensure the home meets current safety and building codes.
Second story addition - Capitol Hill Seattle Grande Dame

Thick Floor Layers

Keeping existing ceilings often leads to a thicker floor structure.

Many second-story additions keep the original ceiling intact to minimize disruption to the rooms below. A new floor system is then built on top, resulting in a floor that’s thicker than usual. This added thickness can impact stair design, layout, and the overall exterior proportions of the home.
Stair - Capitol Hill Seattle Grande Dame

Rethink the stairs

Think creatively when placing the stairwell.

Stairs can take up a significant amount of floor space, so thoughtful planning is essential. In some cases, the ideal solution is a modest bump-out to accommodate the stairwell—and perhaps even create a more welcoming front or rear entry. Incorporating skylights or feature lighting can also transform the staircase into a striking architectural feature.
Vaulted ceiling - Capitol Hill Seattle Grande Dame

Add ceiling height

Vaulted ceilings add light and space.

If your new roof design allows, using scissor trusses or stick framing can allow the introduction of vaulted ceilings in key areas—making spaces like the primary bedroom or a family room feel open, airy, and luxurious. There are also ways to increase ceiling height in the existing main level, though this typically requires more extensive remodeling.
Dormer addition - Ballard Seattle Sugi Ban

Heat it right

Separate systems = better comfort and control.

Second-story additions often require a dedicated HVAC system to ensure optimal comfort. One of the most effective solutions is installing a compact ducted system in a conditioned attic, efficiently serving all major spaces in the addition. This setup is discreet, energy-efficient, and allows for independent temperature control of the upper floor. For enhanced zoning and flexibility, ductless mini-splits offer ever greater comfort and control, providing targeted cooling or heating to each bedroom or living space.
Second story addition bathroom - Capitol Hill Seattle Grande Dame

Plumbing matters

Bathroom locations impact layout and cost.

Adding a bathroom upstairs requires integration with the existing drainage system, often necessitating pipe routes through floors and walls below. This must be factored into the design, as it can impact structural planning. Identifying these constraints early helps avoid costly and disruptive modifications in construction. A well-conceived design anticipates drain paths from the outset, working within the existing conditions to minimize unnecessary alterations.
Second story addtion den - Capitol Hill Seattle Grande Dame

Beyond bedrooms

Plan for flexible, shared-use spaces.

Your second floor doesn’t have to be all bedrooms. Consider including a den, study nook, or playroom—spaces that allow flexibility as your needs change. Even small areas like a stair landing or hallway can be turned into something useful with thoughtful design.
Second story addition bedroom - Capitol Hill Seattle Grande Dame

Timing is everything

Seattle’s seasons affect build schedules.

Expect 4-6 months for design and permits, and 9-12 months for construction. Summer is an ideal time to begin construction, particularly if the existing home isn’t undergoing extensive remodeling. To ensure a smooth process, it’s best to start designing a second-story addition in the preceding fall or winter.

Our expertise turns the complexity of second story addition design into clarity. Book a free consultation or call 206-204-0490 to discuss your project.

Schedule a call

Design powered by advanced technology

Technology - 3D Point Cloud Scanning

3D Point Cloud Scanning

Capturing your existing structure conditions with accurate data so we can create better models in BIM to serve your vision. And help you design for the master plan for your future. Seeing a bigger picture.
The BIM Advantage for Architectural Design

Building Information Model (BIM)

We use Revit, a Building Information Modeling (BIM) software that is beneficial for a range of projects, from single-family residences and partial remodels to larger commercial and facility developments.
Technology - Visualization

Visualization

Since a BIM workflow operates in 3D throughout our design process, we can add detail directly to our schematic designs and provide 3D visualizations that help you better understand how the proposed spaces will feel.
Technology - Lighting Analysis

Lighting Analysis

The BIM model allows us to integrate the precise location of your project, enabling us to address site-specific solar questions and accurately determine the sun’s position relative to your modeled project at any given time and date. As a result, you can see how light will interact with your project before construction begins!

We’ll help you figure out how—and who—will build it

Be your own contractor

For hands-on homeowners comfortable acting as their own general contractor, managing construction and hiring subcontractors directly.

  • You get the lowest construction cost
  • You avoid markup and overhead
  • You have full control over subcontractors
UBuildIt

Partner with UBuildIt

For homeowners who want to stay involved, get expert support, and potentially save up to 30%.

  • UBuildIt manages pricing and schedule
  • You hire subcontractors directly
  • You pay UBuildIt a fixed consulting fee

Hire a general contractor

For owners who’d rather hand things off to a pro who can keep the project moving and handle the details.

  • We help match you with the right contractor
  • Contractors provide rough pricing estimates (ROM)
  • We help with selection and planning

How to estimate construction cost + design fees

— this and many other topics all covered in our Project Planner

Trust + Satisfaction

See what it’s like working with us.

Loading...