Breaking news and resources from across the industry.

Martha Rose Construction: 5-Star City Cabins at Abbott's Alley

Posted on Jun 1, 2021 in:
  • Case Studies

This small enclave of City Cabins at Abbott’s Alley is comprised of six live upstairs/work downstairs units located in the rural community of Sedro-Woolley, right in the heart of Skagit County. These homes have all of the healthy home and energy efficiency features you’d expect in a Martha Rose Construction project, which is why this project was awarded a 2020 Built Green Hammer Award. Martha Rose not only builds green, but lives green, and is a proud homeowner of one of the six homes she built.

Vital Stats



Location: Sedro-Woolley
Star Level: 5-Star, Net Zero Energy Label
Checklist: 2018 Single-Family/Townhome
Verifier: Balderston Associates
Site and Water 202
Energy Efficiency 273
Health and Indoor Air Quality 158
Material Efficiency 133
  Total Score 837

The dead-end alley was named after Edson “Dad” Abbott, who brought Dream Theater to Sedro-Woolley in the 1930s, ushering in and fostering a sense of community for the town. To honor this history, the end of the alley provides a new “Dream Theater” as a gathering spot for movies, music, and other outdoor events. This feature proved to be a crucial community amenity during the COVID-19 quarantine, allowing community members to gather outside with masks and plenty of distance to safely enjoy movies together and share stories around the firepit.

Creating homes that provide for a flexible lifestyle was a key component of the project. The ground floors are fully accessible; they are set up for a future kitchen, have private entrances, and include a bathroom with an accessible shower. City zoning mandated commercial use on the ground floor, but banks don’t typically like mixed-use homeowner mortgages. The solution was to build individual structures that meet single-family criteria for a traditional homeowner mortgage loan, but also satisfy the requirements of the land use code. The International Residential Code acknowledges these live/work units as single family. Despite being a novel idea in this town when first proposed, this last year has been a good reminder that reviving the old way of “living above the shop” has a myriad of benefits.

Martha Rose Construction Built Green 5-Star Sedro Woolley live/work cabin exterior

With a simple design and careful attention to construction details, Martha Rose Construction was able to achieve a HERS Index of -10 on each of the six live/work homes in this enclave in downtown Sedro-Woolley. This was accomplished through a variety of techniques, including the “Martha Wall,” excellent air sealing, beefed-up insulation, and careful attention to equipment choices. A 9.9 kW solar array tops each building. Martha shared that, “After living in my home for three winters, I’ve never used all of the electricity generated on the roof, even with charging an EV!” Construction materials were chosen for health, proximity to the job site, easy maintenance, durability and beauty. Hard surfaces were used on the floors and there is no crawl space. Plumbing fixtures meet or beat WaterSense criteria.

Despite the high percentage of impervious surface, 100% of the stormwater is managed on site. The city allowed the project to install a giant infiltration basin made of railroad ballast under the paved alley. The 160 yards of granite ballast provide the structure for the road while providing 40% voids to contain rainwater while it slowly seeps into the ground.

Homeowners benefit from the Marth Rose’s detailed focus on indoor air quality. Five fresh air changes every day, made possible with a very high efficiency heat recovery ventilator that runs continuously, is one leg of the healthy home strategy. During the 2020’s wildfire smoke-filled air, these homes were smoke-free. During the pandemic, these homes offered a higher level of protection because of the year-round conditioned fresh air.

Martha Rose Construction Built Green 5-Star Sedro Woolley live/work cabin living and dining room
Martha Rose Construction Built Green 5-Star Sedro Woolley live/work cabin first floor commercial space
Martha Rose Construction Built Green 5-Star Sedro Woolley live/work cabin exterior alleyway and dream theater

Built Green Highlights

Site and Water

  • 40% void infiltration bed below development manages 100% of stormwater onsite
  • New landscaping emphasized native vegetation
  • Existing vegetation that was removed was replanted or donated for reuse
  • No turf grass
  • Pesticide-free integrated pest management plan
  • Low-flow plumbing fixtures
  • High efficiency 0.8 GPF toilets
  • Main floor is an accessible studio/commercial space

Energy Efficiency

  • HERS index -10
  • 120% better than code, Net Positive Energy!
  • 100% electric, fossil-fuel free operations
  • 9.9 kW solar PV on each unit
  • EV charging ready
  • Energy Star and DOE Zero Energy Ready Home certified
  • R-20 sub-slab insulation
  • Blown-in cellulose walls and ceiling (~85% recycled content)
  • Blower door score of 1.2 ACH
  • "Martha Wall" utilizes 1" of closed-cell foam under the exterior plywood for continuous thermal break

Health and Indoor Air Quality

  • EPA Indoor airPLUS certified
  • No carpet in the units
  • No garages
  • All paints, finishes, and materials are low-VOC and NAUF
  • Roof overhangs of 24” and 36”
  • Heat recovery ventilators with ECM motors

Materials Efficiency

  • Deconstructed existing 600 SF house and reused onsite salvaged materials
  • Used locally salvaged lumber for concrete forms, siding, and finish shelving
  • Interior walls designed for flexible spaces
  • Abundant use of local and regional materials
  • Polished concrete slab floor
  • Cork stair treads
  • Metal siding installed
  • Pantry with open shelves, cabinets, and counters using local, recycled materials and some steel
  • Reclaimed diamond blocks for landscape walls


Help us build a sound future.