More space, same address
Home Additions in Tigard.
Add a backyard ADU or expand the home you have. De Marco Builders is an ADU builder in Tigard that designs, permits, and builds new living space, with a guaranteed contract price and a completion date we meet. Home additions in Tigard start here.
space For every chapter
ADUs & Home Additions Built Around You.
Tigard homeowners like to make the most of their properties. A guest suite for visiting relatives. A home office with a door that closes. A rental unit with its own entrance. A place for a parent to live close by. A well-planned ADU or addition makes all of that possible without packing a single box.
We start with who will use the space, how often, and how it connects to the rest of your property. Design, permitting, and construction all run through one team, so what you approve on paper is what you walk into.
The foundation
Where Great Construction Starts.
An ADU or addition is a structural project before it’s a design project. Foundations, framing, rooflines, and connections to your existing home all have to work together, and the quality of that work shapes how the space performs for years to come.
That makes it a management job as much as a building job. De Marco Builders coordinates every trade, inspection, and delivery under a single plan, and we’ve done it across more than 1,400 projects in the Portland metro. For a home addition contractor in Tigard, that oversight keeps the build on schedule and the structure sound.
THE PROCESS
What to Expect from an ADU or Home Addition.
Your project begins with a conversation about what you need, what you want to invest, and what your property allows. From there, we develop the design, handle the permit paperwork, and walk you through a clear, itemized proposal before anything starts.
You’ll know the price and the finish date before the first day of construction, and we stand behind both. With transparent pricing and a 100% on-time record, De Marco Builders keeps your project on track from start to finish. Request a free quote to get started.
WHY DEMARCO
Why Tigard Clients Choose Us.
Tigard's longest-serving custom builder
In business since 1996, we know Tigard's neighborhoods, soils, permits, and inspectors better than anyone.
Fixed price, fixed schedule
What we quote is what you pay. The date we give you is the date we hit. No surprise change orders, no surprises, no exceptions — not once in over 1400 construction projects in the Portland metro.
One team from start to finish
Design, permits, construction — same crew, same point of contact, from the first site walk to the day we hand you the keys. No gaps in accountability, no finger-pointing when something needs to be fixed.
Award-winning craftsmanship
Recognized by Portland Monthly, the NW Natural Street of Dreams, BuildZoom, Nextdoor, and BusinessRate.
Family-owned since day one
Same owners, same values, nearly three decades running. You work with the people whose name is on the door.
Serving all of Portland Metro
From Tigard to Lake Oswego, Beaverton, Hillsboro and every Portland neighborhood in between.
Our Services
Everything We Build in Tigard
FAQ
Common Questions.
Can't find the answer you're looking for? Reach out and we'll get back to you within one business day.
Do you offer free estimates?
Yes
How long does a typical project take?
It depends on the size, scope, design complexity and permit process.
Typical project timelines include:
- ADUs: 45–60 days
- Home Additions: 45–90 days
- Remodels: 30–90 days
- Custom Homes: 90–160 days
- Commercial Projects: 90–160 days
How do you price a project?
Every proposal from De Marco Builders provides complete cost transparency. Our estimates clearly show the construction costs, company overhead, profit, and total project cost so clients fully understand where every dollar is allocated.
Do you require a deposit?
No. Never. We do not require an upfront deposit. The first payment is due only after a portion of the contracted work has been completed.
What happens if costs change during the project?
We guarantee the contract price through project completion unless the homeowner requests additional work beyond the original scope or unforeseen structural conditions are discovered that were not visible during the initial evaluation.
Can you work within a specific budget?
Absolutely. De Marco Builders is a budget-driven builder. We work within the client’s established budget throughout the design, engineering, permitting, and construction phases. We utilize value-engineering principles to maximize quality while maintaining budget goals.
Are you licensed, bonded, and insured?
Yes. De Marco Builders is fully licensed, bonded, and insured. We maintain all required certifications and operate in full compliance with state regulations.
How do you handle unexpected issues that come up mid-project?
Unexpected issues are rare because of our extensive experience and thorough planning process. If an unforeseen issue does arise, it is addressed immediately, typically within 24 hours. We resolve issues in a code-compliant manner while protecting the project schedule.
How often will I receive updates?
Communication is one of our highest priorities. Once a client signs a contract, we maintain frequent communication throughout design, engineering, permitting, and construction. Clients receive regular progress updates, photos, and end-of-day reports so they remain informed from start to finish.
Our Projects
Recent Work
A Home Renovation in NE Portland
De Marco Builders completed a full interior and exterior renovation, transforming a 1936 NE Portland home into an updated Portland […]
More Room to Grow: A Restaurant Expansion in Hillsboro
De Marco Builders delivered this commercial build in Hillsboro, Oregon — a new banquet room, a redesigned entrance, and a […]
Design-Build Custom Home in Portland
See how De Marco Builders transformed a 900 sq ft 1946 bungalow into a 2,400 sq ft custom home in […]
Ready to Build Something
You'll Love?
Get a free consultation with our team — no commitment, just a conversation about what's possible.
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