Design Development Process
Navigate from initial concept to final construction documents like a seasoned developer
The $2.3 Million Design Decision:
Two developers hire the same architect for identical 60-unit apartment projects. Developer A rushes through design development in 6 weeks, pushing for quick construction documents. Developer B invests 14 weeks in systematic design development, coordinating MEP consultants, value engineering sessions, and three full design iterations. Result: Developer A discovers $2.3 million in design conflicts during construction—clashing HVAC ducts, undersized electrical rooms, inefficient unit layouts. Developer B’s thorough process caught every issue on paper where changes cost $200, not $200,000. The difference? Understanding that design development isn’t a phase to rush through—it’s where projects succeed or fail.
1. The Five Phases of Architectural Design Development
Professional design development follows a proven sequence. Skip a phase or rush through, and you’ll pay for it in construction. Master this process, and you’ll build better projects for less money.
📐 The Professional Design Development Roadmap
Phase 1: Programming & Pre-Design
Purpose: Define what you’re building and why
Key Activities:
- Space Programming: List every room, size, and relationship
- Site Analysis: Understand constraints and opportunities
- Code Research: Identify regulatory requirements
- Budget Setting: Establish cost parameters
- Goals Documentation: Define success metrics
Deliverables:
Program Document: Room-by-room requirements
Site Analysis: Opportunities and constraints map
Project Goals: Written objectives and priorities
💰 Cost Impact Decisions:
Building Size: Every 1% reduction saves $50-100k
Quality Level: Sets expectation for finishes
Efficiency Targets: Rentable vs. gross area ratio
Phase 2: Schematic Design (SD)
Purpose: Explore design options and establish basic concept
Key Activities:
- Concept Development: Multiple design options
- Massing Studies: 3D form and scale
- Site Planning: Building placement and circulation
- System Selection: Structural and MEP approach
- Preliminary Layouts: Basic floor plans
Deliverables:
Site Plan: 1:200 scale showing building location
Floor Plans: 1:200 scale basic layouts
Elevations: All four sides, basic massing
3D Views: Massing model perspectives
✅ Approval Requirements:
Owner Review: Concept approval before proceeding
Planning Department: Informal review recommended
Budget Check: Rough cost estimate ±20-30%
Phase 3: Design Development (DD)
Purpose: Refine and coordinate all building systems
Key Activities:
- System Coordination: MEP, structural integration
- Material Selection: Exterior and interior finishes
- Detail Development: Wall sections, connections
- Code Compliance: Ensure all requirements met
- Consultant Coordination: All disciplines aligned
🤝 Consultant Integration:
Structural Engineer
Column locations, beam depths, lateral system
MEP Engineer
Equipment rooms, shaft sizes, ceiling heights
Civil Engineer
Grading, utilities, stormwater management
Landscape Architect
Planting design, hardscape, irrigation
Deliverables:
Detailed Plans: 1:100 scale, all levels
Building Sections: 2-4 sections showing systems
Wall Sections: 1:20 scale typical details
MEP Layouts: Coordinated system drawings
Material Boards: Finish selections
Phase 4: Construction Documents (CD)
Purpose: Create complete instructions for building
Key Activities:
- Technical Drawings: Every detail documented
- Specifications: Written requirements for materials
- Dimension Control: Complete dimensional information
- Detail Library: Standard and custom details
- Permit Set: Code compliance documentation
📑 Document Components:
Architectural (A)
- Site plan (A0.1)
- Floor plans (A1.1-A1.x)
- Roof plan (A1.R)
- Elevations (A2.1-A2.4)
- Sections (A3.1-A3.x)
- Wall sections (A4.1-A4.x)
- Details (A5.1-A5.x)
- Schedules (A8.1-A8.x)
Structural (S)
- Foundation plan
- Framing plans
- Structural details
- Structural schedules
MEP (M/E/P)
- Mechanical plans
- Electrical plans
- Plumbing plans
- Riser diagrams
Phase 5: Construction Administration (CA)
Purpose: Ensure design intent during construction
Key Activities:
- Shop Drawing Review: Verify contractor submittals
- RFI Responses: Clarify design questions
- Site Visits: Observe construction progress
- Change Orders: Evaluate and document changes
- Punch Lists: Final quality control
⏱️ Typical Response Times:
Shop Drawings: 7-10 business days
RFIs: 3-5 business days
Change Requests: 5-7 business days
Site Issues: Same day if critical
2. Cost Implications of Design Decisions
Every line on a drawing has a dollar sign attached. Understanding when and how design decisions impact cost separates profitable projects from budget disasters.
💰 The Cost Influence Curve
Key Principle: Your ability to influence project cost decreases dramatically as design progresses, while the cost of making changes increases exponentially.
Programming (100% influence)
Cost to change: $0 – Just updating documents
Impact potential: Can affect 40-50% of project cost
Example: Reducing building from 5 to 4 stories saves $2M
Schematic Design (80% influence)
Cost to change: $5,000-15,000 in design fees
Impact potential: Can affect 25-30% of project cost
Example: Changing from steel to wood frame saves $800k
Design Development (50% influence)
Cost to change: $15,000-50,000 in redesign
Impact potential: Can affect 15-20% of project cost
Example: Optimizing mechanical systems saves $400k
Construction Documents (20% influence)
Cost to change: $50,000-150,000 to revise drawings
Impact potential: Can affect 5-10% of project cost
Example: Changing window types saves $100k
Construction (5% influence)
Cost to change: $200,000+ including delays
Impact potential: Usually adds cost, rarely saves
Example: Moving a wall costs $50k vs $500 on paper
🎯 Major Design Decisions and Their Cost Impact
Structural System Selection
Wood Frame (Type V)
Cost: $85-110/SF
Height Limit: 4 stories typical
Speed: Fastest construction
Best for: Apartments, condos under 60 units
Light Gauge Steel
Cost: $95-125/SF
Height Limit: 4-6 stories
Speed: Moderate
Best for: Hotels, senior housing
Concrete Podium
Cost: $120-150/SF
Height Limit: 5-7 stories
Speed: Slower first floor
Best for: Mixed-use with parking
Structural Steel
Cost: $150-200/SF
Height Limit: No practical limit
Speed: Moderate to fast
Best for: High-rise, long spans
Building Envelope Decisions
MEP System Selection
3. Design Phase Cost Impact Calculator
Build your own cost model using REAL local data:
💰 Real-World Design Decision Cost Tracker
⚠️ Before You Start:
This calculator requires YOU to research actual costs in your market. Contact 3 local contractors, check RS Means, or use recent project data. This is how professionals actually estimate!
🎯 Understanding How Construction is Priced:
Critical Concept: Different building components are priced by different units!
📐 Structure (per SF of building)
Priced by total floor area
Example: 50,000 SF building × $120/SF = $6M
🧱 Exterior (per SF of wall)
Priced by vertical wall surface only
Example: 24,000 SF walls × $45/SF = $1.08M
🔧 MEP (per unit or SF)
HVAC by unit, central systems by SF
Example: 50 units × $3,500/unit = $175k
💡 Key Insight: A 50,000 SF building might only have 20,000-30,000 SF of exterior walls. That’s why exterior finish costs per SF of wall look different when spread across the whole building!
Step 1: Define Your Project
Step 2: Enter YOUR Local Costs (Research Required!)
Base Construction Costs (per SF of BUILDING):
These costs are based on total building square footage (all floors combined)
Exterior Systems (per SF of WALL area):
⚠️ Important: These costs are per square foot of exterior WALL surface only, NOT per square foot of building! The calculator will automatically calculate wall area and show the impact on overall building cost.
MEP Systems (per unit or SF):
Individual systems are priced per unit, central systems per SF of building
Step 3: Model Your Design Decisions
Step 4: Document Your Analysis
📚 Where to Find Real Cost Data:
- RS Means: Industry standard cost database (subscription required)
- Local GCs: Call 3-5 general contractors for budget estimates
- Recent Bids: Public project bids are often available online
- Industry Reports: Turner Construction Cost Index, Mortenson Cost Index
- Trade Associations: AGC, ABC chapter cost surveys
- Your Network: Other students may share regional data
4. Coordinating with Consultants and Engineers
A building is a complex system of systems. Success requires orchestrating multiple consultants like a conductor leading a symphony—everyone plays their part at the right time.
🤝 The Consultant Coordination Matrix
When Each Consultant Joins the Team:
Programming Phase
Essential: None typically needed
Optional: Specialty consultants for complex programs
Schematic Design
Essential:
- Civil Engineer – Site feasibility
- Structural Engineer – System selection
Optional:
- MEP Engineer – Major system decisions
- Geotechnical – If site conditions unknown
Design Development
Essential:
- All engineering disciplines (S, M, E, P, FP)
- Landscape Architect
- Civil Engineer – Full involvement
Optional:
- Acoustical Consultant
- Lighting Designer
- Security Consultant
📋 Coordination Best Practices
Design Team Meeting Structure:
Weekly Coordination Meetings
Duration: 1-2 hours
Attendees: All active consultants
Agenda:
- Progress since last meeting
- Coordination issues
- RFIs and clarifications
- Upcoming deadlines
- Action items
Milestone Reviews
Frequency: End of each design phase
Purpose: Comprehensive coordination check
Key Reviews:
- 30% DD – Major systems locked in
- 60% DD – Full coordination check
- 90% DD – Final coordination
- 50% CD – Constructability review
Essential Coordination Tools:
BIM/Revit Model
Purpose: 3D coordination and clash detection
Best Practice: Weekly model uploads from all disciplines
Key Benefit: Find conflicts before construction
Overlay Drawings
Purpose: 2D coordination check
Best Practice: Architect overlays all consultant drawings
Key Benefit: Quick visual conflict identification
Coordination Checklists
Purpose: Systematic review process
Best Practice: Phase-specific checklists
Key Benefit: Nothing falls through cracks
RFI Log
Purpose: Track all clarifications
Best Practice: Cloud-based, real-time updates
Key Benefit: Clear communication trail
⚠️ Common Coordination Failures and Solutions
Ceiling Height Conflicts
Problem: Structural beams, ducts, and sprinkler lines all fighting for same space
Cost Impact: $50,000-200,000 to resolve in field
Solution:
- Establish ceiling height matrix in DD
- Create typical ceiling coordination sections
- Model critical areas in 3D
- Lock in beam depths early
Mechanical Room Sizing
Problem: Equipment doesn’t fit in allocated space
Cost Impact: $100,000+ to relocate or resize
Solution:
- Size mechanical rooms in SD with engineer input
- Include maintenance clearances
- Consider equipment replacement path
- Add 15% space buffer
Structural Penetrations
Problem: MEP systems need holes through beams/slabs not shown
Cost Impact: $500-5,000 per penetration
Solution:
- MEP rough layout in SD
- Penetration schedule by 60% DD
- Coordinate all vertical shafts
- Show all sleeves on structural drawings
5. Case Study: The Power of Proper Design Development
How one developer’s investment in design development turned a potential disaster into a profit center:
🏢 The Project: Meridian Mixed-Use Development
Project Details:
Location: Downtown Seattle
Program: 180 apartments, 20,000 SF retail, 200 parking spaces
Site: 0.92 acres, sloping site with view potential
Budget: $52 million initial projection
The Design Development Process:
Week 1-2: Programming Deep Dive
Discovery: Market analysis showed strong demand for smaller units
Decision: Shifted from 150 large units to 180 efficient units
Impact: +$2.4M in projected revenue, same building size
Week 3-6: Schematic Design Options
Explored: 3 different massing schemes
Decision: Tower placement to maximize views
Impact: +$15/month premium rent for 120 units = $216k/year
Week 7-14: Design Development Intensity
Actions Taken:
- 5 full-team coordination meetings
- 3D BIM model with clash detection
- Value engineering sessions with GC
- Detailed systems coordination
Critical Discoveries:
Issue 1: Structural system conflict with parking layout
Solution: Adjusted column grid, saved 10 parking spaces
Value: 10 spaces × $40k = $400k additional value
Issue 2: MEP routes blocked view corridors
Solution: Rerouted systems to maintain premium views
Value: Preserved $2.1M in view premiums
Issue 3: Inefficient mechanical room placement
Solution: Consolidated and relocated, gained 2 units
Value: 2 units × $450k = $900k additional revenue
Week 15-16: Final DD Package
Deliverables: Complete coordinated drawings
Cost Estimate: GMP at $51.2M (below budget!)
Schedule: Identified 2-month acceleration opportunity
Project Outcomes:
Without Proper DD (Projected)
- Construction Cost: $54M (+$2M overrun)
- Schedule: 20 months + 3 month delays
- Lost Revenue: $1.8M from delays
- Change Orders: $2.5M estimated
- Total Units: 178 (lost 2 to conflicts)
- Rental Premium: Standard rates only
With Proper DD (Actual)
- Construction Cost: $51.2M (under budget)
- Schedule: 18 months (2 months early)
- Bonus Revenue: $600k from early delivery
- Change Orders: $340k (minimal)
- Total Units: 180 (gained 2)
- Rental Premium: +$15-25/unit for views
Financial Impact Summary:
DD Investment: $180,000 extra time and fees
Construction Savings: $2,800,000
Revenue Gains: $3,600,000 (from units and premiums)
ROI on DD Investment: 3,444%
🔑 Developer’s Key Takeaway:
“That extra $180k and 8 weeks in design development made us $6.4 million. It’s not a cost—it’s the best investment you can make in a project. We found and fixed $2.5 million in conflicts on paper where it cost us nothing but time.” – Project Developer
⚡ Design Development Challenge
Navigate a Real Design Development Scenario (30 minutes):
You’re managing design development for a 40-unit apartment building. Practice making critical decisions:
🏢 Project: Urban Flats Development
Program: 40 units (20 one-bedroom, 20 two-bedroom)
Site: 0.75 acres urban infill
Budget: $8 million construction
Current Phase: 30% Design Development
Your Role: Development Manager coordinating the design team
Design Development Challenges to Resolve:
Challenge 1: Ceiling Height Conflict
The structural engineer’s beams are 24″ deep, HVAC ducts need 18″ vertical space, and you promised 9′ ceilings in units. Floor-to-floor height is only 11 feet.
Math: 11′ floor-to-floor – 24″ beam – 18″ duct – 12″ floor = 7′-6″ ceiling (NOT 9′!)
Your Decision Options:
- Increase floor-to-floor height to 12′-6″ (+$320,000)
- Run ducts through beams with penetrations (+$45,000)
- Change to post-tension slab for 8″ structure (+$180,000)
- Lower ceiling height to 8′-6″ and adjust marketing (saves $500/unit)
Challenge 2: Mechanical Room Crisis
MEP engineer needs 800 SF for equipment. Architect allocated 500 SF. Each SF of mechanical room = lost rental income.
Financial Impact: 300 SF × $25/SF/month × 12 months = $90,000/year lost revenue
Resolution Strategies:
- Give up apartment unit for mechanical space (-$2,000/month)
- Go to rooftop equipment with screening (+$125,000)
- Use high-efficiency equipment needing less space (+$85,000)
- Distribute to multiple smaller rooms (coordination challenge)
Challenge 3: Value Engineering Pressure
GC’s budget came in $600k over. Need to cut costs without sacrificing quality or marketability.
Your Design Development Action Plan:
DESIGN DEVELOPMENT DECISION LOG
- PROJECT: Urban Flats – 40 Units
- DATE: [Current Phase: 30% DD]
- ATTENDEES: Developer, Architect, Engineers
- CHALLENGE 1: CEILING HEIGHT CONFLICT
- Issue: 7′-6″ ceiling vs 9′ marketed height
- Decision: _________________________________
- Rationale: _________________________________
- Cost Impact: $_____________
- Schedule Impact: _____________
- Action Items: _________________________________
- CHALLENGE 2: MECHANICAL ROOM SIZE
- Issue: Need 800 SF, have 500 SF allocated
- Decision: _________________________________
- Rationale: _________________________________
- Revenue Impact: $_____________/year
- Coordination Required: _________________________
- CHALLENGE 3: VALUE ENGINEERING
- Target: Reduce costs by $600,000
- Selected VE Items:
- 1. _______________________ Savings: $_________
- 2. _______________________ Savings: $_________
- 3. _______________________ Savings: $_________
- Total VE Savings: $_____________
- CONSULTANT COORDINATION PLAN:
- Immediate Actions: _____________________________
- Next Meeting Focus: ____________________________
- Drawing Updates Needed: ________________________
- Critical Path Items: ___________________________
- LESSONS LEARNED:
- What worked: __________________________________
- What to improve: _______________________________
- Applied cost influence principle: _______________
🎯 Design Development Mastery
Design development follows 5 distinct phases, each with specific deliverables
Cost influence decreases dramatically as design progresses
Changes during construction cost 100x more than during design
Consultant coordination prevents expensive field conflicts
3D modeling and clash detection save millions in change orders
Value engineering should enhance, not compromise, project quality
✅ Design Development Knowledge Check
Question 1:
At which design phase do you have maximum ability to influence project cost?
Question 2:
What percentage of design time is typically spent on Construction Documents?
Question 3:
When should MEP engineers be fully engaged in the design process?
Question 4:
What is the primary purpose of Design Development phase?
Question 5:
Moving a wall during construction vs. design typically costs:
Question 6:
What is the most effective tool for finding conflicts between building systems?
Question 7:
In the case study, what was the ROI on the extra design development investment?
Question 8:
Which consultant coordination meeting is most critical?
🎯 Ready to Complete Lesson 39?
Take the quiz to finish this lesson and move forward with value engineering.
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