What Tom Bassett-Dilley Architects does

Tom Bassett-Dilley Architects (TBDA) is a boutique sustainable architecture and consulting firm headquartered in Oak Park, Illinois, serving residential homeowners, commercial entities, institutional clients, and other architecture firms across the Chicago metropolitan area and select Midwest states (Illinois, Wisconsin, Michigan, Indiana). Founded in 2006 by Tom Bassett-Dilley after leaving a prior position to pursue climate-responsive, ecologically grounded architecture, the firm has completed approximately 100 high-performance new homes, renovations, and retrofits over its operational history. Client segments include individual homeowners seeking Passive House or LEED-certified homes, park districts and educational institutions requiring LEED Platinum community buildings, multifamily developers pursuing Phius certification, and peer architecture firms contracting TBDA for Phius consulting and energy modeling.

TBDA's core methodology integrates Passive House (Phius) design principles with LEED and decarbonization strategies, executed through in-house energy modeling using WUFI-Passive software. The firm provides a portfolio of services including Passive House (Phius) design and consulting, residential and commercial/institutional green architecture, decarbonization and deep energy retrofit consulting, Net Zero design, and LEED/Living Building Challenge certification. Technical capabilities are anchored by multiple Certified Passive House Consultants (CPHCs) on staff, with expertise in thermal envelope optimization, building science analysis, electrification planning, and historic preservation retrofitting. Projects span Phius Source Zero, DOE Zero Energy Ready Home, LEED Platinum/Gold, and Net Zero certifications, with the firm recognized as one of only 19 AIA 2030 Commitment firms meeting 80% predicted EUI reduction targets out of 428 reporting firms in 2022.

TBDA operates a sales-led professional services model, with design fees typically set at 10-15% of construction cost on multi-year project contracts, and construction costs for new homes and gut renovations ranging from $320-$380 per square foot and above. The firm does not use intermediaries, relying on direct client engagement, referrals from peer firms (e.g., Mark Miller Architecture), industry recognition, and thought leadership (2025 PhiusCon opening keynote, national awards) to acquire projects. Revenue is project-based and variable depending on the mix of residential commissions, multifamily consulting engagements, and institutional work. The firm maintains a small team (1-10 employees) with no external investors, parent company, or public financial disclosure.

Name

Tom Bassett-Dilley Architects

Legal name

Tom Bassett-Dilley Architects

Website

https://tbdarchitects.com

Company type

Private

Founded year

2006

Operating status

Operating

Headcount range

1–10 employees

Short description

Tom Bassett-Dilley Architects is a boutique sustainable architecture firm in Oak Park, Illinois, specializing in Passive House (Phius), LEED, and decarbonization design for residential and commercial clients across the Chicago metropolitan area and Midwest.

Ownership category

akta.pro rank

Product category

Sustainable Architecture Services

NAICS

Environmental Consulting Services (541620)

akta.pro primary industry

Sustainable/Green Building & LEED Consulting (BPAHAKAG)

Keywords

• Passive House design
• Sustainable architecture services
• LEED consulting
• Decarbonization consulting
• Energy modeling services

Headquarters

HQ city

Oak Park

HQ country

United States

HQ region

North America

Offices1 record

Markets served

GTM type

B2B and B2C

Offering type

Services

Cost components

Personnel, Operations, Marketing or Sales, Technology or R&D, Infrastructure

Revenue model

1. Architecture and Design Services: Professional services revenue generated from architectural design, consulting, and project management for residential, commercial, and institutional projects. The firm provides both design services and consulting support for Phius certification and decarbonization projects.

Pricing tiers

Go-to-market motion1 record

Distribution channels1 record

Marketing channels5 records

Core offering

TBDA is a boutique sustainable architecture firm offering architectural design, energy modeling, and consulting services for residential, commercial, and institutional clients. Core services include Passive House (Phius) design and certification consulting, residential green architecture, commercial and institutional design, decarbonization and deep energy retrofits, Net Zero design, and LEED/Living Building Challenge design. The firm integrates Passive House principles, LEED design, and decarbonization strategies to deliver energy-efficient, healthy buildings in the Chicago metropolitan area and broader Midwest.

Product overview

Tom Bassett-Dilley Architects (TBDA) is a boutique sustainable architecture and consulting firm offering a portfolio of green building services. The firm's core offerings include Passive House (Phius) design and consulting, residential green architecture, commercial and institutional design, decarbonization and deep energy retrofit services, Net Zero design, and LEED/Living Building Challenge certification design. The services integrate energy modeling, building science analysis, and sustainable design principles to deliver healthy, energy-efficient, and environmentally responsible buildings. TBDA also showcases completed projects including Passive Houses, LEED-certified buildings, historic retrofits, and net zero developments across residential and commercial categories.

Differentiator

Problem solved

Functional benefit

Named customers8 records

Segments3 records

Ideal customer profiles3 records

Technology focussed No

API detail

Has API

No

API docs

API detail

Core technology

AI maturity

App detail

Feature3 records

Partnerships

Six partnerships are on record, tiered core and minor.

• Oak Park Residence CorporationcoreStrategic or Co-development PartnerOwner of the Pierce at 7 Van Buren, a 44-unit mixed affordable and market-rate apartment building. TBDA provides Phius consulting services for this significant multifamily project, working with the design team through energy modeling iterations and certification support. The project received a grant from Illinois Clean Energy Community Foundation requiring demonstrated net zero energy performance.
• Ware MalcombcoreStrategic or Co-development PartnerArchitecture firm engaged as design architect on the Pierce at 7 Van Buren project. TBDA provides Passive House expertise and Phius certification consulting support to bring the design team up to speed on Passive design principles.
• EcoAchieverscoreTechnology or IntegrationThird-party Rater/Verifier providing quality control inspections during construction, testing and verification services, and valuable multifamily-specific design and construction expertise relevant to Phius certification.
• Illinois Green AllianceminorChannel Partner/ Reseller/ DistributorRegional green building organization. TBDA participates in joint events including home tours and educational presentations. TBDA's Right Sized Passive House won Outstanding Single-Family Project in USGBC LEED Home Awards.
• PhiuscoreTechnology or IntegrationPassive House US certification body. TBDA staff hold Certified Passive House Consultant (CPHC) credentials and provide Phius certification consulting and energy modeling services aligned with Phius standards.
• Synergy GroupminorImplementation/ SI/ Consulting PartnerGeneral contractor on the Pierce at 7 Van Buren project. Participated in Phius Builders Training and contributes to discussions about materials and constructability of air barriers and other Passive House elements.

Scale indicators6 records

Recent moves7 records

Expansion highlights5 records

Direct peers

• ZeroEnergy Design: Boutique Passive House architecture and consulting firm; similar size, same Phius methodology, and comparable residential/light-commercial focus — the closest direct peer to TBDA's consulting-plus-design model.
• Atelierjones: Seattle-based boutique firm practicing sustainable architecture across residential and small institutional projects with comparable attention to health, energy performance, and material sourcing.
• Positive Energy: New Mexico-based high-performance residential architecture firm specializing in Passive House; comparable boutique scale and similar Phius certification depth.
• Onion Flats: Philadelphia-based design-build firm specializing in Passive House, modular construction, and sustainable urban infill; comparable in technical depth and high-performance residential focus, with a larger multifamily tilt.
• SHED Architecture & Design: Pacific Northwest boutique firm known for net-zero and Passive House-adjacent residential design; similar firm size and project typology, serving a different region.
• Caleb Johnson Architects: Maine-based boutique firm focused on Passive House and sustainable residential architecture; comparable scale and deep technical specialization in Phius/energy modeling.

Broad incumbents

• BNIM Architects: National sustainable design firm with deep expertise in net-zero, Passive House, and decarbonization across commercial, institutional, and multifamily projects; larger scale and broader geography than TBDA.
• Lake|Flato Architects: Established, multi-office firm with a strong sustainability and regional-vernacular design ethos; broader portfolio and greater capacity than TBDA, but operates in adjacent high-performance design space.
• Olson Kundig: Large, award-winning architecture practice known for high-performance and sustainably-minded residential and hospitality projects; broader portfolio and geographic reach but operates in the same high-end sustainable design category.

Emerging players

• Interface Architects: Boutique firm with growing portfolio in sustainable residential and small commercial work; partial overlap with TBDA in decarbonization/retrofit consulting but a smaller installed project base.

Market position

Strengths4 records

Weaknesses4 records

Competitive moat4 records

Key risks5 records

Key highlights6 records

Customer concentration

• LinkedInlinkedin.com/company/tbdarchitects
• Xx.com/TBDArchitects
• Facebookfacebook.com/tbdarchitects

Compliance21 records

Revenue estimate

Valuation estimate

Number of profiles

Profiles5 records

Funding overview

Funding rounds

Investors

Funding detail is available on the Subscription and Enterprise plan.Contact sales →

M&A

Investments

M&A and investment is available on the Subscription and Enterprise plan.Contact sales →

Frequently asked questions about Tom Bassett-Dilley Architects