In Your Daily Routine Is Research for Your Self-Build post, we started recording what we like and dislike about the things we use every day. The comfortable bath. The awkward kitchen cupboard. The shower that makes you want to stay in for another five minutes.
Those observations give us the beginnings of a self-build specification. Next, we’re going to make them more useful by adding numbers.
“I want a decent shower” leaves plenty open to interpretation. A measurement gives you something more specific to discuss with your designer or installer, and eventually check in the finished house.
Start with something you like
Take a shower you enjoy using. What makes it good?
It might be the amount of water, the coverage of the spray, or how consistently it holds its temperature. Identify the quality you care about before deciding what to measure.
If it’s the amount of water, you can measure the flow rate in litres per minute using a measuring jug and a stopwatch, for example.
Run the shower at your normal preferred setting. Collect the spray in the jug, capturing all the water, and time how long it takes to reach a known volume. A larger container can help if the spray is too wide.
Calculate:
Flow rate = litres collected × 60 ÷ seconds taken
If you collect 2 litres in 12 seconds:
2 × 60 ÷ 12 = 10 litres per minute
Repeat it a few times to check the result.
This way you can explicitly record: “This shower feels comfortable at approximately 10 litres per minute.”
It is just one example of applying an actual number to a real world use that you may want to replicate in a future home.
Apply the same approach elsewhere
You don’t need to measure everything, just start with the experiences that matter most to you.
| Your observation | What to measure | What to record |
|---|---|---|
| This bath is comfortable | Internal length, width and backrest shape | Dimensions, model if known, and who found it comfortable |
| Two people can work in this kitchen easily | Clear distance between opposing units | The gap, plus whether movement still works with drawers or appliances open |
| The toilet roll is easy to reach | Holder position relative to the toilet | Measurements and a photograph, checked by the people who will use it |
| There’s enough room for everyone at dinner | Table size and usable space around it | Number seated, table dimensions and room to pull chairs out |
| The washing dries without taking over a room | Drying space and time | Size of a normal load, rail length used and drying conditions |
Some qualities need more than one measurement. A bath’s length alone won’t capture its comfort, and drying time depends on ventilation, temperature and the clothes themselves.
Record enough context to make the number useful later.
Turn the measurement into a target
Your existing home gives you reference points. You can then decide which ones to carry into the specification.
For each requirement, write down:
- Attribute: What matters to you?
- Metric: How will you measure it?
- Target: What should the finished house achieve?
- Priority: Must, Should or Could?
- Test: How will you check it?
Discuss that target with the designer or installer. They can check it against the proposed water supply, hot-water system and other demands in the house.
A provisional target gives that conversation a starting point. You can revise it as you understand the practical implications. In the shower example it may be that water saving becomes a higher priority in an Eco Home so you may decide to compromise.
Decide how you’ll check it
Put the test alongside the requirement now.
If you want to be able to manoeuvre around an open dishwasher comfortably, mark out the proposed kitchen and try it. If you want a reachable toilet roll holder, test its position before permanently mounting. If you want a particular shower flow, agree the product spec matches your own.
Check things while changes are still straightforward. Some requirements can be tested with a tape measure or a mock-up. Others, such as ventilation performance or airtightness, will need the appropriate specialist testing.
Add three measured requirements to your specification
Choose three entries from your likes and dislikes log. Identify what matters, add a measurement, then write a provisional target and a way to check it.
Keep the original observation beside the numbers. It explains why the requirement exists and helps you judge alternatives later.
Your specification now starts to describe how you’ll know the finished home works for you and can guide your later snags list.