QFD analysis, mapped.
Also called: Quality Function Deployment · House of quality · Voice-of-customer mapping · Customer-to-engineering matrix
A simple translation table that connects what customers want to the engineering choices that deliver it, so design effort goes where it counts.
List what customers want. List the engineering characteristics that could deliver each want. Score how strongly each one helps. The scores tell you which characteristic earns the most attention. For the proofing box, temperature stability wins by a mile.
What QFD analysis is
QFD has a frightening name and a friendly job. Think of it as a translator sitting between two people who do not speak the same language. On one side is the customer, saying things like “I want a prove that never fails” and “it should look good on the counter.” On the other side is the engineer, who deals in numbers: temperature held to half a degree, watts drawn, millimetres of insulation. QFD is the table that lets the two sides talk.
The full method draws this table as a diagram with a peaked roof and calls it the “house of quality.” Ignore the roof for now. The useful part is the body of the house, a plain grid. Down the left you write the customer wants, in the customer’s own words. Across the top you write the engineering characteristics, the things you can actually measure and design. Then, cell by cell, you ask one question: how strongly does this characteristic help deliver that want? Strong, medium, weak, or nothing.
Weight the customer wants by how much they matter, multiply through, and the columns add up. The characteristic with the highest total is the one your design effort should chase first. That is the whole trick. It turns “everything feels important” into a ranked list you can defend, because the ranking came from the customer, not from whoever argued loudest in the room.
Here is the grid we filled in for the proofing box, so you can see the shape of a real one rather than a textbook diagram.
Read the right-hand column top to bottom and the message is hard to miss. Temperature stability outranks everything. So the engineering hours, the prototype testing, the BS EN 61010 safety work around the heater, all of it should cluster there first. Finish and price matter, but they serve a box that has to hold temperature before anything else is worth a penny.
- “The finish sells it, so polish the ceramic first.”
- “Everyone loves an app, let’s add a screen.”
- Effort spread evenly because nothing was ranked.
- The loudest voice in the room sets the order.
- Temperature stability ranked highest, so it gets the first hours.
- Each characteristic traces back to a stated customer want.
- Effort follows the scores, not the strongest opinion.
- The ranking is written down and anyone can challenge it.
The gut-feel column is not stupid; every item on it is something a sensible person might say. The trouble is that none of it is anchored to what the customer actually weighted, so the order is an accident. The mapped column reaches the same characteristics but knows why each one sits where it does.
How it fits the bigger picture
QFD analysis is the last activity of Stage 05 Define. By now the design brief, the specification, and the value goals all exist as words. QFD turns those words into a ranked engineering target, which is exactly what Stage 06 Design needs to start drawing. It is the handover note from “what we want” to “how we will build it.”
What it can do
It gives the design team a defensible order of attack. When time runs short, and it always does, QFD says where to spend the next hour. It also catches the orphan, an engineering characteristic that maps to no customer want, which is usually a feature someone added because it was interesting rather than because anyone asked for it.
What it can’t do
It can’t invent the customer wants or measure them for you. Garbage in, garbage out: if the wants on the left come from a hunch rather than from Stage 02 Discover’s research, the ranking just dresses up a guess. And it ranks; it doesn’t design. The clever solution to “hold 26°C cheaply” still has to be engineered in Stage 06.
See the full 10-stage process →
Try it yourself
Take five customer wants in their own words and weight each one out of nine for how much it matters. List the engineering characteristics that could deliver them. For every want-and-characteristic pair, score the link strong, medium, weak, or nothing. Multiply by the weights, total the columns, and the highest column is where your design effort starts. Half an hour with a spreadsheet beats a week of arguing.
Want the guided version first? Start the Free Sprint → and the GPT will help you surface and rank the wants before you map them.
Your QFD checklist
Project notes: the column that settled the argument
▸ From the notebook · optional reading
Filling the house of quality with Dan and Anna Hartley in Stockport, and how one column ended a fortnight of circular debate about where to spend the budget.
3 min read · click to open
Dan called QFD “the scary spreadsheet” the first time I mentioned it. By the end of the afternoon he was running it himself. The trick was refusing to draw the famous peaked roof; we just built the plain grid and filled it in.
What went on the page
Down the left we put four wants, in their words: a prove that never fails, no fuss, looks good on the counter, fair price. Across the top, the things we could actually measure: temperature stability, thermal mass, control simplicity, finish quality, power draw. Then I asked the only question that matters: “For each box, how hard does this characteristic pull on that want? Strong, medium, weak, or nothing.”
The argument it settled. For a fortnight the team had gone back and forth: spend the prototype money on a gorgeous ceramic finish, or on the heater-control electronics? Anna leaned finish, because finish is what sells a £149 object in a John Lewis. Dan leaned electronics. Neither could win because neither had a number.
When we totalled the columns, temperature stability scored highest by a clear margin. Every want except “looks good” pulled on it strongly, and even the never-fails want, weighted top, mapped almost entirely to it. Finish quality scored well but second. The grid had answered the question they’d been arguing about for two weeks.
The orphan we found
The grid caught something else. We’d been carrying a “temperature graph” idea as a possible characteristic. When we tried to map it to a customer want, it mapped to nothing. Nobody had asked to watch a graph; they’d asked for a prove that never fails. Into the V2 backlog it went, and the conversation closed in a minute.
I am wary of methods that promise to remove judgement from design, and QFD does not do that. What it did was make the team’s judgement visible and shared, so the budget went to the heater control first and the finish second, in that order, with everyone agreed on why.
— Define stage, project notes, 2026
— Next stage → Stage 06 · Design