Envelope first
Air tightness targets and thermal bridge details are drawn before cladding selections.
Sustainable architecture · Seattle
Buildings that earn their energy back.
Hearthline designs net-ready offices, housing, and schools with measured envelopes, electrified systems, and commissioning plans owners can operate—not only plaques on opening day.
Performance baked into design
Energy models, embodied carbon, and O&M manuals are deliverables—not side studies.
Electrified systems
Heat pumps, ERVs, and panel schedules sized for future PV and battery add-ons.
Modeled outcomes
We publish EUI targets and carbon budgets beside each design option.
Embodied carbon
Material swaps are logged with kgCO₂e comparisons before specs finalize.
Commissioning
Functional tests and trend logs are handed to facilities with alarm narratives.
Operator training
We run handover sessions with screens showing how setbacks actually behave.
Measured impact
- Average EUI reduction vs. baseline
- 42%
- Projects targeting net-zero
- 18
- Embodied carbon avoided
- 1,200 t
- LEED Platinum certifications
- 11
Net-ready office retrofit
Phasing a 1980s tower without displacing tenants.
- 2026
Electrification complete
Boilers replaced with heat pumps; roof PV online with tenant-aware metering.
- 2025
Envelope upgrades
Window replacements and roof insulation done floor by floor on nights and weekends.
- 2024
Baseline + modeling
Blower door tests and energy model established owner targets and incentives.
Owner notes
“Our EUI dropped 38% in year one—and operators finally understand the setbacks.”
“Embodied carbon swaps were documented so our lender could underwrite the timber upgrade.”
“Commissioning caught a VAV issue before occupancy—saved us a summer of complaints.”
Performance team
- Sofia AlvarezPrincipal, passive design
- Jonah WeissEnergy model lead
- Amira SolCommissioning director
Sustainability FAQ
Do you certify projects?
We lead LEED, WELL, and Living Building consultations with certifier coordination.
Can you retrofit occupied buildings?
Yes—phased envelopes and overnight mechanical swaps are our specialty.
How do you handle incentives?
We map utility rebates and document models for incentive reviewers.
What about mass timber?
We partner with structural engineers on fire, acoustics, and moisture details.
Do you monitor after opening?
Optional M&V retainers compare actual EUI to modeled targets.
Can you work with our CM?
We issue commissioning specs and attend prefunctional checklists on site.
How early should we involve you on a campus master plan?
Before land is purchased we can model solar access, stormwater, and EUI targets so each building inherits a shared carbon budget.
Tell us about your building
Share square footage, fuel type, and occupancy—we reply with a performance baseline proposal.
Targeting net-zero on your next lease?
We benchmark your portfolio, model tariff shifts, and identify the three upgrades with the fastest payback and the lowest disruption.