Quality Function Deployment House of Quality
What is Quality Function Deployment?
QFD is a rigorous method for translating customer needs, wants, and wishes into step-by-step procedures for delivering the product or service. While delivering better designs tailored to customer needs, Quality Function Deployment also cuts the normal development cycle by 50%, making you faster to market.
QFD uses the "QFD House of Quality" to help structure your thinking, making sure nothing is left out.
QFD Example
The QFD House of Quality template, is one of many tools found in QI Macros Six Sigma add-in for Excel.
There are four key steps to QFD thinking:
1. Product Planning- Translating what the customer wants (in their language, e.g., portable, convenient phone service) into a list of prioritized product/service design requirements (in your language, e.g., cell phones) that describes how the product works. It also compares your performance with your competition's, and sets targets for improvement to differentiate your product/service from your competitor's.
2. Part Planning - Translating product specifications (design criteria from step 1) into part characteristics (e.g., light weight, belt-clip, battery-driven, not hard wired but radio-frequency based).
3. Process Planning - Translating part characteristics (from step 2) into optimal process characteristics that maximize your ability to deliver Six Sigma quality (e.g., ability to "hand off" a cellular call from one antenna to another without interruption).
4. Production Planning - Translating process characteristics (from step 3) into manufacturing or service delivery methods that will optimize your ability to deliver Six Sigma quality in the most efficient manner (e.g., cellular antennas installed with overlapping coverage to eliminate dropped calls).
Even in my small business, I often use the Quality Function Deployment template to evaluate and design a new product or service. It helps me think through every aspect of what my customers want and how to deliver it. It saves me a lot of "clean up" on the backend. It doesn't always mean that I get everything right, but I get more of it right, which translates into greater sales and higher profitability with less rework on my part.
That's the power of QFD.
QFD Steps
In this walkthrough, let’s use the “Product Planning” tab for reference:
- First, you want to define what the customer wants...their requirements. Then, input those requirements in cells B9 and B12.
- Once you have done so, you'll need to define those requirements into characteristics. Input these characteristics into cells C8:C13. Also, please note that you can add rows or remove rows...meaning, it is not required to have exactly 3 different characteristics for each requirement.
- Next, assign a level of importance to each of these characteristics - 1 for least important and 5 for most important. These values are placed in cells D8:D13.
- Then, what different aspects of each characteristic is included in your process? You would input those in cells E7:I7...and again, you can have as many or as few aspects as you would like - it doesn't need to be exactly 5 aspects.
- Once you have defined those aspects, assign either a 9 (high), 3 (medium), or 1 (low). This value will indicate how much the aspect relates to that requirement. E.g., "Design Criteria 1" is VERY impactful to the Quality requirement, however, has very low impact on the Speed requirement:
- And please note that the values found in cells D8:I13 inform the “Absolute Importance” totals found in cells E20:I20. These results let you know which aspects should be focused on the most, as they are calculated from the 1, 3, 9 values assigned from the criteria portion, as well as the Level of Importance assigned in Column D:
- Once you have completed the task of assigning not only the Level of Importance, but also the Design Criteria table, you can then begin to fill out the “Strong +/Positive/Negative/Strong -“ portion of the template:
- As well as the (2) Company vs. Competitor Rating and Evaluation tables:
- And lastly, the “Targets” portion of the template:
Learn more about QI Macros' QFD Template