Jason Allen Contracting, LLC

Portland ADU is a residential design-build contractor based in Portland, Oregon, specializing in Accessory Dwelling Units (ADUs), home additions, basement conversions, kitchen remodeling, bathroom remodeling, and custom residential renovations. Founded by Jason Ali Allen, the company has more than 25 years of construction experience, combining craftsmanship, architectural vision, and practical project management to help homeowners maximize their property’s living space and value. With a strong focus on Portland’s unique housing stock and zoning regulations, Portland ADU creates functional, energy-efficient living spaces tailored to each homeowner’s goals.

Operating as a full-service design-build firm, Portland ADU manages every stage of the project—from feasibility consultations and master planning to architectural design, engineering, permitting, and construction. As a recognized Field Issuance Remodel (FIR) Contractor, the company benefits from a streamlined permitting and inspection process through the City of Portland, helping clients complete projects more efficiently. Whether building a detached backyard ADU, converting a basement into a rental unit, or expanding an existing home, Portland ADU emphasizes thoughtful design, durable construction, and transparent communication throughout the entire process.

Services

• Accessory Dwelling Units (ADUs)
• Detached ADUs
• Basement ADUs
• Garage Conversions
• Home Additions
• Basement Remodeling
• Kitchen Remodeling
• Bathroom Remodeling
• Custom Homes
• Dormer Additions
• Historic Home Remodeling
• Tiny House Utility Hookups
• Water & Fire Restoration
• Master Planning
• Property Development Consultations
• Architectural Design
• Engineering Services
• Permit Coordination
• Design-Build Services
• General Contracting
• Project Management

Why Choose Portland ADU?

• Over 25 years of residential construction experience
• Complete design-build services under one roof
• In-house designer and engineering coordination
• Handles all permits and city approvals
• Certified Field Issuance Remodel (FIR) Contractor
• Specialists in detached and basement ADUs
• Extensive experience with Portland’s historic homes
• Transparent project planning and consultations
• High-quality craftsmanship with premium finishes
• Personalized service led by founder Jason Ali Allen