aia ntap conference set based design
DESCRIPTION
The construction industry is one of the only industries with declining productivity. Tools like BIM, IPD, and Lean aim to reverse this trend. Set-based Concurrent Design is a Lean alternative to the traditional iterative design loops and enables projects to be designed 10 to 15 times faster.TRANSCRIPT
Set-based Concurrent DesignEric Peabody
The Design Partnership ■
Architects + Planners
415 345-3813
Set-based Concurrent Design What is Set-Based? Set-Based Detailing Set-Based Design Choosing by Advantages Results
Why Do We Care?
What is Set-Based Design?
• Iteration in design is part value added and part waste– Understanding the problem and range of
solutions is value added– Rework and time delay is waste
• “Posing alternative design solutions as sets, rather than as point solutions is the strategy at the heart of…set-based design.”
• (Ballard, Lean Construction Institute, “Positive vs Negative Iteration in Design”)
Iterative Loops
Set-based Design
Iterative Design Set-Based Design• Sequential processing adds
time• Release incomplete work for
others to start evaluating• Simultaneous evaluation of
options
• Select best alternative as quickly as possible to move to next stage
• Carrying multiple options allows more time for analysis
• Defer commitment to avoid premature decisions with incomplete knowledge
• One design contribution can invalidate all previous work
• Identifying a problem with an option reduces the design space but does not trigger rework
Set-Based Detailing
SET 1
SET 2SET 3
Set-Based Design1. Divide design into interchangeable
chunks
2. Multiple simultaneous designs for each chunk
3. Evaluate Combinations
4. Select a combination set• Choosing by Advantages
5. Swap chunks at roadblocks
VA Palo Alto, Aquatic Center
Design Sets: Massing
Design Sets: Roof Structure
Design Sets: Skin Design
Design SetsCombinations: n1*n2*n3…nn= many sets
Massing: 7 optionsRoof Structure: 4 optionsSkin Design: 6 options
7*4*6=168 design sets
Which is the best option?
Choosing by Advantages• The Fundamental Rule of Sound Decision-making:
• Decisions must be based on the importance of advantages.• Pros & Cons = double counting
1. Identify Attributes:• Cake vs Cereal for Breakfast
• Calories• Taste
2. Identify Difference in Attribute Value:• Cake for breakfast = 500 calories• Cereal for breakfast = 200 calories
• Difference = 300 calories
Choosing by Advantages3. Identify Advantage
• Calories:• Cake has 300 more calories• Cereal has 300 fewer calories• Advantage:
• Cereal’s advantage is 300 fewer calories • Cake has no calorie advantage
• Taste: • Cake tastes very good.• Cereal tastes okay.• Advantage:
• Cake’s advantage is it tastes much better • Cereal has no taste advantage
Choosing by Advantages4. Evaluate the Importance of the Advantage
5. Select the option with the highest Advantage• Cereal for breakfast
Cake CerealCalories
No Advantage 0 300 Fewer Calories 10
Taste Tastes Much Better 5 No Advantage 0
5 10
Selecting an Option
9 55 0
0 12 1
0 88 0
0 106 10
0 83 3
7 50 0
16 3724 14
The Design Partnership LLP
Architects + Planners
Swap Chunks• Initial Client Selection
• Massing: Courtyard• Roof Structure: Bow String• Skin Design: Green Screen w/ Translucent Top
• Road block 1: Roof maintenance safety• Keep Massing & Skin Design• Trade Roof Structure: Flat for Bowstring
• Road block 2: 30% scope increase• Keep Skin Design & Roof Structure• Trade Massing: New Massing Option
• Road block 3: Contextuality• Keep Massing & Roof Structure• Trade Skin Design: Rainscreen for Green Screen
The Design Partnership LLP
Architects + Planners
Radically Accelerated Schedule
• Typical Project Schedule: • 30 to 45 minutes per SF for design.
• Radically Accelerated Schedule:• 30,000 SF in 4 months – Programming through CD
3 minutes per SF for design (10 to 15 times faster)
Set-based Concurrent DesignEric Peabody
The Design Partnership ■
Architects + Planners
415 345-3813