Posts in CAST Projects
AIA 2030 Commitment

As an AIA 2030 signatory firm, CAST has committed to its goal of carbon-neutral buildings by 2030. This Commitment is an actionable climate strategy that offers a set of standards and goals for reaching net zero emissions in the built environment.

Our design approach and process are thoughtful. We push the limits of sustainability through project performance by setting clear goals and making a positive impact on the environment. Our expertise helps our clients align with their green building goals and understand building life-cycle costs, lower utility bills, enjoy the benefits from natural light, and manage water usage.

The latest climate data tells us that reducing carbon emissions is not enough. To make the biggest impact, we must commit to net zero emissions by 2030—a path that requires strong, immediate action. Since the built environment creates a staggering 40% of the world's emissions, architects, engineers, and owners play a key role. We know that every project can be a catalyst for change.

Our Sustainability Action Plan includes principles and commitments that look for smart, innovative ways to deliver our projects and support climate goals.
Principles
Think Holistically
Act with Urgency
Every Project Counts
Make the Next Project Better

Commitments
Measure Performance
Support Research
Commit to AIA 2030 Challenge
Iterate on Success
Work with Partners
Advocate for Change
Celebrate Wins

See our Sustainability Action Plan here: www.castarchitecture.com/sustainability-action-plan

CAST is dedicated to tracking and reporting our progress toward the AIA 2030 Commitment. We will utilize energy modeling, life cycle assessments, and post-occupancy evaluations to measure operational energy use and embodied carbon across our projects. Our team will document and submit project performance data to the AIA Design Data Exchange (DDx), responding with transparency and accountability. By setting measurable benchmarks and analyzing trends, we will refine our strategies, improve outcomes, and contribute to industry-wide efforts to achieve carbon neutrality. Through this commitment, we will continuously push the boundaries of sustainable design while sharing insights that drive collective progress.

We have had deep roots in sustainable design since our founding in 1999. We are committed to improving the lives of individuals, families, and the community through vibrant and thoughtful design. CAST is at the forefront of sustainable architecture, creating high-performance buildings designed to endure. Our approach prioritizes responsible resource management throughout a building’s lifecycle, integrating climate-responsive design, the best available building science, and site-specific strategies.

ADU + DADU: Living Small, Living Well

Accessory Dwelling Units (ADUs) and Detached Accessory Dwelling Units (DADUs) are transforming the housing landscape in urban areas. These self-contained small homes, can be attached or stand-alone and are becoming increasingly popular in cities grappling with housing shortages, rising costs, and shifting lifestyle preferences.

Help Housing Shortages
The surge in demand for housing has put significant pressure on urban neighborhoods, where space is limited and housing affordability is a critical issue. ADUs and DADUs offer a practical solution by increasing the housing stock within existing neighborhoods.

Affordability + Flexibility
ADUs and DADUs provide an affordable alternative for renters and homeowners alike. Homeowners can use these units as rental properties, offering housing at a lower cost than traditional apartment units. They can also serve as multi-generational living spaces, allowing families to stay connected while maintaining privacy. For many, ADUs are a way to downsize without leaving their neighborhoods, contributing to economic diversity in communities.

Ease Zoning Regulations
Cities across the US are revising zoning laws to encourage the construction of ADUs and DADUs. These policy changes make it easier for homeowners to build these units by reducing permitting costs, relaxing parking requirements, and increasing maximum allowable sizes. In Seattle, for example, pre-approved DADU plans streamline the process, saving time and money for homeowners.

Sustainability
These small homes align with urban densification goals. By utilizing existing infrastructure and minimizing the need for new developments these homes help reduce urban sprawl. Additionally, their smaller size typically results in lower energy consumption.

Enhance Community Character
Thoughtfully designed DADUs can blend seamlessly into existing architectural styles, adding diversity to the housing stock while preserving the integrity of the neighborhood.

See more: www.castarchitecture.com/backyard-cottages-new

CAST's Matt Hutchins focuses on innovative solutions to promote accessible, medium-density housing

Matt Hutchins addresses the critical issue of “missing middle” housing in the U.S., exploring the housing gap that falls between single-family homes and high-density apartments. Serving as a jury member for the Denver Single-Stair Housing Challenge organized by Buildner, he focuses on innovative solutions to promote accessible, medium-density housing options.

Watch on YouTube: https://www.youtube.com/watch?v=orW8tnmPSv0

Missing-middle housing is a housing type that fits in the middle between single-family detached houses and larger apartment buildings. That’s duplexes, tri-plexes, four-plexes, ten-plexes, and small apartment buildings. It’s any sort of increment of density that is greater than a single-family house, but isn’t the blocks of apartment buildings that is much of what we see in the development world today. Missing-middle housing is important for urban development because American cities have lots of space. They are nowhere near full. We have empty parking lots. We have lots that were never developed. We have space in our cities we can use or reuse. There are many opportunities within our cities to densify and make use of existing infrastructure without having to assemble a whole block or use more “high-wire acts” with regard to development.

• Make good use of small lots

• Use of single-stair buildings is a critical tactic for taking advantage of small urban lots

• Adapt building regulations and make required changes

• Use underutilized urban land

• Use space correctly

• We have already invested in the urban infrastructure

• We can have a more efficient city and residents with a lower carbon footprint

• ADUs and DADUs are powerful tools to keep communities together, keep the property in family, and create generational wealth

• Missing-middle housing is compact, efficient, and sustainable


middle housing toolkit

Introducing CAST’s Infill Housing Toolkit: We put together recent, current, and future projects to showcase strategies and case studies for abundant housing infill development.

Site
Typologies
Constrained Lots
Typical Infill Lots
Large, Assembled Lots

Design Features
Single Stair
Stacked Flats
Low-Energy Design
Low-Carbon Building
Diverse Unit Mix
Open Space

Kirkland Cedar Cottage

The Kirkland Cedar Cottage shines. It has an extremely efficient footprint that provides well daylit living space, necessary storage, flexibility, and a covered outdoor living area.

Bathed in natural light, a generous central area includes the kitchen, dining, and living spaces. The cottage is accessible with one-level living, flush entry thresholds and flooring transitions, a galley kitchen, and a generous entry that connects the spaces. 

Carefully placed large windows and glass entry doors flood the area with light that bounces off the white walls to make it feel larger than its square footage. The open glass doors and deep eaves create a vibrant indoor/outdoor living experience.

Square feet: 467

Green Design: Energy-efficient heating, cooling, and water heating systems, passive solar heat gain in window/shading, all LED lighting, low VOC recycled and renewable materials, and no fossil fuel use appliances.

Interior Designer: Jayne Douglas Design
Builder: NW Finishing
Photos: Kara Mercer

This cottage was recently featured in Kirkland Lifestyle.

Green design elements prominent in the Methow Valley's RiversMeet

RiversMeet, a mixed-use project in the town of Winthrop in Washington’s Methow Valley, is positioned to become the upvalley entrance to “old downtown.” The site is a challenging set of narrow parcels overlooking the confluence of the Methow and Chewuch Rivers.

RiversMeet is envisioned as a template for how buildings can work within Winthrop's westernization code while striving for high levels of sustainability and providing more inclusive housing options.

The program will provide two 2-bedroom residential units overlooking the river, with approximately 1,870 SF of pedestrian-level retail space. The second floor incorporates 1,870 SF of office space. The second floor incorporates 1,870 SF of office space, continuing the client’s tradition of renting below market rate to community non-profit businesses.

GREEN DESIGN
1. Concrete mix uses fly ash, reducing use of higher-carbon cement
2. Low-Carbon Foamed Glass Aggregate replaces typical underslab foam board insulation
3. Gutex wood fiber exterior board insulation
4. Low-Carbon Wildfire Resistance Strategy:
- Wood siding treated with a non-toxic solution that provides fire resistance without the high carbon penalty of fiber cement
- Exterior sprinkler system
- Fiber cement siding reduced to areas where it's most effective
5. FSC-certified wood framing package
6. High-efficiency all-electric heat pump space heating
7. High-efficiency heat pump water heating
8. Solar array

TEAM
Client: Peter Goldman and Martha Kongsgaard
Architect: CAST architecture
Builder: North Star Construction Company  www.Northstarbuilds.Com
Civil & Structural: DCG, now Facet   www.dcgengr.com  
Electrical: TFWB   tf-wb.com
Environmental:  Grette  www.gretteassociates.com 
Geotech: Geoengineers  www.geoengineers.com/ 
Mechanical: Ecotope   www.ecotope.com 
Survey: Tackman   www.tackmansurveying.com

Passive House design certified apartment building in Seattle

ECHO, a 10-unit apartment building in the Eastlake neighborhood of Seattle, is now a Design Certified PHIUS (Passive House Institute US) Core 2021 project.

This apartment building will replaces a single-family structure in this residential urban village, adding missing-middle housing. It utilizes the stacked flats concept which pushes the bounds of the single-family envelope but maintains an urbanism-friendly street frontage.

The two homes on the ground floor are both fully accessible. And, the top two units have high ceilings with lofted sleeping areas.

High-performance design elements include: thermal control, airtightness and moisture control, balanced ventilation, and high-performance glazing.

TEAM
Developer: West Crescent Advisors, LLC, Nancy Melton
Architect: CAST
Passive House Institute US: @passivehouseinstituteus
Builder: Carrig Construction @carrig_construction
Project Consultant: Woodworth Construction Management LLC, Lydia Anne, @woodworth_built
Civil Engineer: Davido Consulting Group, Inc. @dcgengr
Structural Engineer: Harriott Valentine Engineers @harriottvalentine
Mechanical Engineer: Ecotope @ecotope_inc
Envelope Consultant: B.E.E Consulting, LLC
Electrical Engineer: TFWB Engineers, Inc
Windows: Alpen Windows – Passive House Certified
Landscape Architect: @karenkiestlandscapearchitects
Arborist: Moss Studio
Geotechnical Engineer: PanGEO, Inc.
Surveyor: Terrane @terranesurveying
Third party verifier: Balderston Associates

RiversMeet Winthrop Proposed Mixed-use building

ON THE BOARDS - METHOW VALLEY’S RIVERSMeet WINTHROP proposed MIXED-USE BUILDING

RiversMeet, a proposed mixed-use project in the town of Winthrop in Washington’s Methow Valley, is positioned to become the upvalley entrance to “old downtown.” The site is a challenging set of narrow parcels overlooking the confluence of the Methow and Chewuch Rivers.

CAST’s client, Peter Goldman, as part of his development proposal, intends to request the town make zoning changes to allow for long-term rentals in the commercial district. RiversMeet is envisioned as a template for how buildings can work within Winthrop's westernization code while striving for high levels of sustainability and providing more inclusive housing options.

The program will provide two 2-bedroom residential units overlooking the river, with approximately 1,870 SF of pedestrian-level retail space. The second floor incorporates 1,870 SF of office space. The second floor incorporates 1,870 SF of office space, continuing the client’s tradition of renting below market rate to community non-profit businesses.

Team
Client: Peter Goldman and Martha Kongsgaard
Architect: CAST architecture
Builder: North Star Construction Company  www.Northstarbuilds.Com
Civil & Structural: DCG   www.dcgengr.com   
Electrical: TFWB   tf-wb.com
Environmental:  Grette  www.gretteassociates.com  
Geotech: Geoengineers  www.geoengineers.com/ 
Mechanical: Ecotope   www.ecotope.com 
Survey: Tackman   www.tackmansurveying.com

Sitka Cottage

New Sitka Cottage: 3-bedroom DADU

At 1,000 net square feet, the Sitka Cottage features three bedrooms and two baths upstairs, an open living room and kitchen, storage, and an additional powder room tucked away on the first floor.  It fits flexibly on many sites with a walk-out terrace off the living room/kitchen. The three bedrooms upstairs are reasonably sized and work well for a family. Standard, wood-frame construction, vented shed roof, slab-on-grade foundation, careful placement of windows, and a simple exterior allow for low-cost construction without sacrificing durability, function, or style.

The design is under the height limit and can fit on standard to small lots, around trees, or on sloped lots, with space for adjacent parking if desired. The cottage can be oriented toward the principal residence for multi-generational living around a courtyard. The front door is on the corner and can be placed on either the short or long side of the design, depending on site orientation.

The design targets 4-Star Built Green, with details for reduced air infiltration, energy-efficient heating, cooling and water heating systems, passive solar heat gain in window/shading in summer, low-VOC finishes, no fossil fuel appliances, and all LED lighting.

See more at CASTcottages.com