From Capital Needs Assessments to Environmental Reviews (HEROS), Energy Reviews, & AEC Services, D3G provides the expert guidance needed to confidently navigate housing compliance & development.

We support housing professionals, lenders, PHAs, developers, nonprofits, & municipalities and property operations with expert consulting to navigate complex regulations, secure funding, & drive impactful housing solutions.

Over the last 30+ years, D3G has transformed into a full-service due diligence & consulting firm—committed to advancing housing through expertise, innovation, & impact.

Learn more about D3G’s culture of innovation, growth, and service—and explore our open roles.

WHO IS D3G FOR?

We've guided thousands of Lenders, Developers, Borrowers, General Contractors, Design Professionals, & Equity Partners through the Due Diligence process.

Let us lead the way through your next HUD, FHA, Fannie Mae, Freddie Mac or RAD real estate financing project. 

30+

Years of D3G

SERVICES

Our Due Diligence Services

Environmental Services

  • Phase I & II ESAs
  • HUD Environmental Reviews
  • NEPA Compliance
  • Radon Testing & Mitigation
  • Asbestos & Lead-Based Paint
  • Mold & Moisture Assessments
  • Industrial Hygiene

Capital Needs Assessments

  • HUD, RAD & LIHTC-Compliant CNAs
  • Green CNA & IPNA Services
  • Mechanical, MEP & Life Safety Reviews
  • Seismic & Obsolescence Testing
  • 20,000+ CNAs Completed Nationwide

Energy & Sustainability

  • Energy Audits & Benchmarking
  • ENERGY STAR & NGBS Certifications
  • Green CNA & IPNA Services
  • Tax Incentives: 45L, 179D, Green MIP
  • GRRP & Sustainability Grant Support

Architectural & Cost Review

  • HUD 221(d)(4) AEC Reviews
  • LIHTC & Tax Credit Compliance
  • Architectural Plan & Cost Reviews
  • New Construction & Rehab Support
  • Adaptive Reuse & Design Feasibility

EMPLOYEE CENTRIC ENVIRONMENT

Innovation Starts With Empowered People

At D3G, we believe our greatest asset is our team. We value the expertise, dedication, and innovation each team member brings to the table. By fostering a culture of growth, collaboration, and continuous learning, we empower our professionals to excel in their careers while delivering exceptional results for our clients. Your talent is what drives our success, and we are committed to supporting your development every step of the way. Join us and be part of a team where your skills and contributions are truly valued.

SERVICES

Our Consulting Services

  • RAD & Section 18 Consulting
  • Repositioning Strategy & Feasibility
  • Voluntary Conversion & Restore-Rebuild
  • Environmental & Policy Compliance
  • Procurement & Development Advisory
  • Building Evaluation Consulting
  • Budget-Based Rental Increases (BBRI/BBRA/202 RAD)
  • Pre-Acquisition Physical Assessments
  • Energy Efficiency & Modeling
  • Accessibility Compliance (UFAS, ADA, FHA)
  • HUD Environmental & Risk Consulting
  • Contamination & Mitigation Strategy
  • NEPA / HEROS Compliance (Part 50 & 58)
  • Climate Risk & Resilience Planning
  • Floodplain & Wetland Consulting
  • HUD Environmental Review Support
  • LIHTC & QAP Green Strategy Support
  • HUD Green Lending (Green MIP, SEDI, SEP)
  • NGBS, LEED, ENERGY STAR & GreenPoint Certification
  • Utility Allowance & Consumption Studies
  • 45L & 179D Tax Credit Guidance

What is HEROS?

We're Champions of the
HEROS Process

HEROS stands for HUD Environmental Review Online System. The platform prepares, manages, shares, and stores supporting documentation to complete Environmental Reviews. The platform’s purpose is to provide a pathway to environmental clearance for HUD/FHA-insured loans, CPD programs like HOME Funds, Community Development Block Grants (CDBG), and Section 8 vouchers.

NATIONWIDE INDUSTRY EXPERTS

Serving the Nation’s
Housing Community
For Over 30 Years.

Serving the Nation’s Housing Community For Over 30 Years.

INDUSTRY EXPERTS

For over 30 years, D3G has been a trusted leader in the housing industry, delivering unparalleled expertise and guidance to clients across the nation.

PASSIONATE PROFESSIONALS

Our dedicated team of passionate professionals has driven innovation and excellence, ensuring every project meets the highest standards of quality and integrity.

NATIONWIDE SOLUTIONS

With a focus on nationwide solutions, D3G has successfully completed thousands of projects, bringing tailored services to communities from coast to coast.

POSITIVE COMMUNITY CHANGES

Through decades of hard work and commitment, D3G has contributed to meaningful, positive changes in communities, enhancing housing opportunities and improving lives.

In 1994, I started D3G as an environmental due diligence firm to fill a gap in the housing market. Over the last 30 years, we’ve grown into a full-service due diligence and consulting partner, supporting housing professionals with strategic guidance. Our mission has always been to drive better housing outcomes through expertise, innovation, and a deep commitment to the communities we serve.

So, I dove in head-first and learned HUD, housing, tax credits, and leveraged finance. D3G expanded our services to include a myriad of housing preservation consulting and we steadily grew.  And all the while, this enforced my belief in quality, sustainable, and affordable housing for Americans. 

– Rob Hazelton
    Founder, CEO

Case Studies

Comprehensive Nationwide
Environmental Solutions
Powered by Expertise

Comprehensive Nationwide Environmental Solutions Powered by Expertise

Dive into our case studies to see how D3G’s wealth of experience and innovative problem-solving have transformed projects across the U.S. and beyond. Our experts bring the knowledge to tackle any challenge.

20K+

Capital Needs Assessments Completed

16K+

Capital Needs Assessments Completed

200K+

RAD Units Assessed

16K+

Years of Industry Experience

20K+

16K+

200K+

30+

Capital Needs Assessments Completed

Environmental Assessments Completed

RAD Units Assessed

Years of Industry Experience

Latest Blog Posts

Stay up to date with the latest industry, environmental, and due diligence news from D3G.