Design-build firms handle both the architectural design and construction execution under one contract—meaning you deal with a single point of contact instead of juggling separate architects and contractors. This integrated approach typically saves 5–15% on project costs and shaves 3–6 months off your timeline. Understanding what's bundled into a design-build contract protects your budget and sets realistic expectations before you sign.
The Core Design Phase
Design-build firms start by meeting with you to define project scope, budget, and timeline. They'll conduct site surveys, assess existing conditions, and pull permits—tasks that usually cost $2,000–$8,000 depending on project complexity. During this phase, your design-build team produces conceptual drawings, 3D renderings, and schematic designs so you can visualize the final product before construction begins.
Most firms include multiple design revision rounds (typically 2–3) in their base fee. Additional rounds beyond that usually trigger change orders at $150–$350 per hour for design time. Clarify revision limits in your contract upfront to avoid surprise costs.
Pre-Construction Services Bundled In
Before the crew breaks ground, your design-build firm handles:
- Detailed construction documentation (blueprints, specifications, material lists)
- Value engineering to optimize costs without cutting corners
- Permit acquisition and inspections coordination
- Subcontractor bidding and selection
- Building code compliance verification
- Site logistics planning (where equipment parks, material storage, traffic flow)
These services typically cost 10–15% of the total project budget when bundled into a design-build contract. If you hire them separately, that percentage often climbs to 18–22%.
Construction & Labor
This is where the bulk of your spending happens. The design-build firm provides:
- General contracting and project management (on-site supervision, daily reporting, schedule tracking)
- Labor and skilled trades (framing, electrical, plumbing, HVAC, finishing)
- Materials procurement (with negotiated supplier pricing, usually better than you'd get independently)
- Quality control and inspections
- Safety compliance and insurance
Construction costs vary wildly by location and scope—residential renovation runs $150–$300 per square foot, while commercial builds range $200–$500+ per square foot. Your design-build firm's contract should spell out what's covered under the fixed price and what triggers change orders (unforeseen structural damage, design modifications, scope creep).
Project Management & Overhead
Design-build contracts always include project management, but verify what that covers:
- Weekly or bi-weekly progress meetings
- Budget and schedule tracking
- Change order processing
- Subcontractor coordination
- Final walkthroughs and punch-list inspections
Some firms include all communication and documentation in their overhead fee; others charge separately for expedited requests, weekend inspections, or extensive change-order reviews. Ask for examples of their typical monthly reporting format before signing.
Warranties & Post-Completion Support
Most design-build firms guarantee workmanship for 1 year and structural elements for longer periods (sometimes 5–10 years, depending on your location and contract). This typically covers:
- Roof leaks caused by installation defects
- Plumbing leaks from faulty work
- Electrical system failures from poor installation
- Structural settling or cracking from construction error
Manufacturer warranties on appliances, HVAC systems, and other components usually run 1–5 years separately and transfer to you. Make sure your contract clarifies who handles warranty claims and which party covers costs.
What's Typically Not Included
Watch out for these common exclusions:
- Owner-furnished materials (you buy finishes, fixtures, or specialty items separately)
- Testing and inspections beyond standard code requirements
- Extended warranties on equipment
- Furniture, landscaping, or décor
- Soft costs like accountant fees or permit expediting
Reading the "scope exclusions" section is as important as reading what's included.
Comparing Contracts
When evaluating design-build firms, request detailed proposals that break down design fees, construction costs, overhead, and contingencies. Mercoly makes it easy to compare multiple design-build firms in your area and find trusted providers—all in one place.
A well-written contract should also define how changes are handled, dispute resolution procedures, and payment schedules (typically tied to construction milestones, usually 10–25% deposits upfront).
Frequently Asked Questions
Q: What percentage of the total project cost goes toward design in a design-build contract? Design fees typically represent 8–15% of total project cost, significantly lower than hiring a separate architect (15–20%) and contractor (general contractor markup of 10–20%) independently.
Q: Can I still hire my own inspector to oversee the design-build firm's work? Yes—third-party inspectors (typically $300–$800 per visit) are common and recommended, especially for larger projects, because they provide objective oversight and documentation.
Q: What happens if the design-build firm discovers hidden structural problems during construction? These usually trigger change orders; the contract should define how discovery is handled and whether costs are shared or absorbed by either party, so confirm this before work starts.
Ready to hire? Use Mercoly to compare local design-build firms side-by-side and request detailed proposals.