Design-Build vs General Contractor: Which Is Right for Your Project?
A straightforward comparison from 40+ years of Arizona construction
Design-build combines architecture and construction under one contract, giving you a single point of accountability, faster timelines, and typically 5–15% lower total cost. A general contractor model separates design from construction, offering more design flexibility but requiring you to coordinate between architect and builder. For custom homes and major renovations in Arizona, design-build has become the dominant model.
How each model works
The fundamental difference is who you hire and how many contracts you sign. Here is how each approach is structured.
Design-Build
You hire a single company that provides both design (architecture, engineering) and construction under one agreement. The design-build firm manages the entire project from concept through move-in. You have one point of contact, one timeline, and one budget.
General Contractor Model
You hire an architect to design the project, then separately hire a general contractor to build it. You manage the relationship between both parties, coordinate communication, and reconcile two separate scopes and timelines.
The Key Difference
In design-build, when something goes wrong the fix is the firm's responsibility. In the GC model, the architect and builder may each point to the other. You become the project manager by default.
Side-by-side comparison
How the two models stack up across the factors that matter most to homeowners.
Pros and cons of each model
Neither approach is universally better. The right choice depends on your project, priorities, and how involved you want to be.
Design-Build
Advantages
- Single point of accountability from design through construction
- Typically 5–15% lower total project cost
- 15–25% faster timelines due to overlapping phases
- Fewer change orders — builder involved during design
- Unified budget with no surprises during bidding
- Less stress — you are not the project manager
Drawbacks
- Design limited to the firm's in-house team or partners
- Less competitive bidding on the construction side
- Must trust one firm to handle everything
- Harder to compare proposals across firms (different scopes)
General Contractor
Advantages
- Freedom to choose any architect or designer
- Competitive bidding between multiple contractors
- Clear separation of design and construction roles
- Architect acts as your advocate during construction
Drawbacks
- You coordinate communication between architect and builder
- Design costs can exceed the construction budget
- Longer timelines — design finishes before bidding starts
- Change orders are more expensive and disruptive
- Finger-pointing risk when problems arise
- Two separate contracts to manage and enforce
Cost comparison
Design-build projects typically cost 5–15% less in total. Here is where the savings come from and how each model breaks down.
Where design-build saves money
Cost breakdown by model
| Cost Category | Design-Build | Architect + GC | Notes |
|---|---|---|---|
| Architect / Design Fees | Included | 8–15% of build | DB firms include design in their contract |
| Engineering | Included | $5K–$25K | Structural, civil, MEP — separate in GC model |
| Permits | Included | $3K–$15K | DB firm handles all permitting |
| Construction | Open-book or fixed | Cost + markup | GC markup typically 15–25% on top of subs |
| Change Orders | Minimal | 5–10% of total | DB catches issues in design phase |
| Project Management | Included | Your time or a PM fee | You are the PM in the GC model unless you hire one |
The hidden cost of the GC model
The most overlooked expense in the architect-plus-GC model is your time. Coordinating between an architect and builder on a custom home project requires dozens of hours of meetings, phone calls, and decision management. If your time has value, this is a real cost.
The second hidden cost is redesign. When the architect's plans come in over the construction budget, you pay for design revisions. In design-build, the budget is integrated from day one, so this problem rarely occurs.
When to choose design-build
Design-build is the strongest choice when accountability, speed, and budget certainty matter most.
- Building a custom home from scratch. The complexity of a ground-up build demands tight coordination between design and construction. Design-build eliminates the gap between what the architect draws and what the builder can deliver within budget.
- Major whole-home remodel. When you are gutting and rebuilding a significant portion of an existing home, the builder needs to be involved during design to identify hidden conditions, structural constraints, and phasing requirements.
- You have a tight timeline. Design-build overlaps design and pre-construction phases, saving 15–25% of the total project schedule. If you need to be in your home by a specific date, this matters.
- You want a single point of contact. If managing two separate firms and reconciling their scopes, schedules, and budgets sounds stressful, design-build removes that burden entirely.
- Budget certainty is your priority. Design-build firms provide a fixed price or open-book budget that includes design, engineering, permits, and construction. No bidding surprises after months of design work.
When to choose a general contractor
The GC model can be the right fit in specific situations where design independence or existing plans are involved.
- You already have architectural plans. If you have invested in a full set of construction documents from an architect you trust, hiring a GC to execute those plans can be the most direct path forward.
- Simple renovation or remodel. For projects that do not involve structural changes or complex coordination — like a cosmetic refresh, flooring replacement, or bathroom update — a straightforward GC relationship works well.
- You want a specific architect's vision. If there is a particular architect whose work you admire and you want their creative direction driving the project, the GC model preserves that relationship.
- The project is primarily cosmetic. Paint, fixtures, hardware, and surface-level updates do not require the integrated approach that design-build provides. A good GC can handle these efficiently.
How Fenn Rogers operates
We are a design-build firm with over 40 years of experience building custom homes in Arizona.
Our approach is straightforward: one team, one contract, one point of accountability. Our in-house design team works alongside our construction team from the first conversation through move-in day. This means the people designing your home understand exactly what it takes to build it — and what it will cost.
We offer fixed-price contracts so you know your total investment before construction begins. No bidding surprises, no budget overruns from disconnected design. When questions come up during construction — and they always do — our team resolves them internally without you playing intermediary.
Every Fenn Rogers project is personally overseen by Jeff or Brady Rogers. We take on a limited number of projects each year so we can stay deeply involved in each one. That is the design-build model done right.
Frequently asked questions
What is design-build construction?
Is design-build cheaper than hiring an architect and general contractor separately?
Do I lose design control with design-build?
How much faster is design-build?
What if I already have architectural plans?
How do change orders work in design-build vs the GC model?
Is design-build better for custom homes?
How do I evaluate a design-build firm?
Ready to discuss your project?
We take on a limited number of projects each year so we can stay personally involved. Tell us about your project and we will help you determine the right approach.