The House of Quality (Harvard Business Review May 1988)
David Segrera
16.842 Systems Engineering
25 September 2009
What is Quality?
• More than avoiding repairs
• Reconcile what consumers want with what can
be built
• Before Industrial revolution
Marketing + engineering +manufacturing = 1 person • Now we must get these different divisions to
talk to each other, how?
The House of Quality
Background
• The House of Quality aka “Quality Function
Deployment” Originated in Japan 1972
Mitsubishi’s Kobe Shipyard
• Others credit two Japanese professors back in the
1960’s (Drs. Yoji Akao and Shigeru Mizuno)
• Graphic tool which links customer needs to
product capabilities
• “focuses and coordinates skills within an
organization, first to design, then to
manufacture and market goods that
customers want to purchase and will continue
to purchase.”
House of Quality
Japanese automaker with QFD made fewer changes than
U.S. company without QFD
• 1st look at customer
needs
• Leads to reduced
prelaunch time and after
launch tinkering
• Toyota 1977-1984 60%
reduction in cost
U.S. company
Design changes
• 2nd Design across
corporate functions
Japanese
company
90% of total
Japanese changes
complete
20-24
Months
14-17
Months
Image by MIT OpenCourseWare.
1-3
Months
+3
Months
Building the House
• 1. Customer Attributes
Roof Matrix Facilitates Engineering Creativity
What do Customers want?
• Take the product to the consumer
and listen
• Market Research: focus groups,
qualitative interviews
• Group CAs into bundels
• Remember customers may be
regulators, or retailers
X
X
+ Road noise reduction
Customer perceptions
1
2
3
4
5
Relationship
Strong positive
X Medium negative
Medium positive
X Strong negative
Image by MIT OpenCourseWare.
lb
lb
lb
Measurement units
Our car door
11 12 13
A'S car door
9 12 6
B'S car door
9.5 11 7
/ft
X
lb
3
2
SealingInsulation
+ Door seal resistance
Energy to close door
Doesn't leak in rain
No road noise
+ Check force on level ground
o
+ Check force on 10 slope
_
7
5
lb
• Comparison with the competition to
identify strategic positioning
Easy to close from outside
Stay open on a hill
ft/
Perceptual Maps
Customer Attributes
Objective
Easy to open
measure Isolation and close door
• 2. Customer Perceptions
Open-close
effort
Engineering characteristics
Relative importance
Not all preferences are created
equal…
• Necessitates tradeoffs, Rank
importance
X
3 9
2 5
2 6
Our Car
A'S Car
B'S Car
Building the House
Roof Matrix Facilitates Engineering Creativity
• 3.Technical Requirements
• Identify engineering characteristics that will effect customer attributes X
X
3
2
lb
ft/
lb
lb
Measurement units
Our car door
11 12 13
A'S car door
9 12 6
B'S car door
9.5 11 7
Relationship
Strong positive
X Medium negative
Medium positive
X Strong negative
Image by MIT OpenCourseWare.
+ Road noise reduction
+ Door seal resistance
1
2
3
4
5
/ft
Doesn't leak in rain
No road noise
Customer perceptions
X
lb
7
5
SealingInsulation
lb
Easy to close from outside
Stay open on a hill
+ Check force on level ground
o
+ Check force on 10 slope
Energy to close door
_
Customer Attributes
Objective
Easy to open
measure Isolation and close door
Open-close
effort
Engineering characteristics
Relative importance
• 4.Relationship Matrix
• indicates how much each engineering characteristic affects each customer attribute based on engineering experience, customer responses and data from experimentation X
3 9
2 5
2 6
Our Car
A'S Car
B'S Car
Building the House
• 5. Targets
X
X
X
X
X
+ Door seal resistance
+ Acoustic transmission, window
+ Road noise reduction
+ Water resistance
3 .10 9 70
2 .10 5 60
2 .10 6 60
1 3 3 5
Imputed importance (%) (all total 100%) 10 6 4
9 1
6
2 4 3
Estimated cost (%)
9 5
6
6 9 2
(all total 100%)
Targets
2
3
4
5
i
lb
ftlb
lb
Measurement units
Our car door
11 12 6 10 18
A'S car door
9 12 6 9 13
B'S car door
9.5 11 7 11 14
Technical difficulty
4 5 1 1 3
ps
3
2
1
X
db
Doesn't leak in rain
No road noise
Customer perceptions
X
/ft
7
5
3
3
SealingInsulation
lb
Easy to close from outside
Stay open on a hill
Easy to open from outside
Doesn't kick back
+ Check force on level ground
o
+ Check force on 10 slope
_
Energy to open door
_
Peack closing force
Engineering characteristics
_
Energy to close door
Relative importance
Customer Attributes
b
lb
• identifies engineering
features that must be
improved collaterally
X
Open-close
effort
ftl
• 6.Roof Matrix
X
X
Objective
Easy to open
measure Isolation and close door
• Objective Measures and
target values
• Additional information:
technical difficulty,
estimated cost, sales data,
etc
X
5 2 2
7.5 9
6 7.5 12
3 .10 9 70
Relationship
Strong positive
X Medium negative
Medium positive
X Strong negative
Image by MIT OpenCourseWare.
Our Car
A'S Car
B'S Car
Using the House
• Connects the what with the
how
X
X
X
X
X
X
X
X
X
• Management
• Displays strategic opportunities
+ Door seal resistance
+ Acoustic transmission, window
+ Road noise reduction
+ Water resistance
Engineering characteristics
SealingInsulation
3
2
lb
lb
ftl
b
Measurement units
Our car door
11 12 6 10 18
A'S car door
9 12 6 9 13
B'S car door
9.5 11 7 11 14
Technical difficulty
4 5 1 1 3
Imputed importance (%) (all total 100%) 10 6 4
9 1
Estimated cost (%)
9 5
(all total 100%)
Targets
5 2 2
7.5 9
6 7.5 12
3 .10 9 70
2 .10 5 60
2 .10 6 60
1 3 3 5
6
2 4 3
6
6 9 2
3 .10 9 70
Relationship
Strong positive
X Medium negative
Medium positive
X Strong negative
Image by MIT OpenCourseWare.
db
ps
i
Doesn't leak in rain
No road noise
1
2
3
4
5
X
/ft
7
5
3
3
Customer perceptions
X
lb
Easy to close from outside
Stay open on a hill
Easy to open from outside
Doesn't kick back
+ Check force on level ground
o
+ Check force on 10 slope
_
Energy to open door
_
Peack closing force
_
Energy to close door
HOW
b
lb
• Expresses the voice of the
customer
Open-close
effort
ftl
• Marketing
WHAT
• Summarizes basic data in
usable form
Customer Attributes
Objective
Easy to open
measure Isolation and close door
• Engineers
Relative importance
• Sets Targets, facilitates
communication about
priorities and goals
Our Car
A'S Car
B'S Car
House to House
• “Principles apply to any effort between
manufacturing functions and customer
satisfaction that are not easy to visualize”
• “The Hows become the Whats”
• the outputs become a starting point for the next
stage in development
House of quality
Parts deployment
Production
requirements
Key process
operations
II
Key process
operations
Parts
characteristics
I
Parts
characteristics
Engineering
characteristics
Customer
attributes
Engineering
characteristics
III
Process planning
IV
Production planning
Linked houses convey the customer's voice through to manufacturing
Image by MIT OpenCourseWare.
Discussion
• Has anyone used this method? What was your
experience?
• Which processes or products lend themselves
well to this type of approach?
• Are there processes and products that do not
work well with this method?
Sources
• John R. Hauser & Don Clausing (1988) The
house of quality. Harvard Business Review,
May-June, 63-73.
• http://www.qfdonline.com
• http://www.qfdonline.com/templates/qfd­
and-house-of-quality-templates/
MIT OpenCourseWare
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16.842 Fundamentals of Systems Engineering
Fall 2009
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