Heating
Looks at fixed heating, heating types, heating safety, and reported winter warmth.
Healthy Homes Score
How we calculate Healthy Homes Scores
This page explains the ratemyflat Healthy Homes Score in plain English. If you want to know what a score means, what goes into it, and how multiple reviews are combined, this is the method.
The short version
Every completed property rating is converted into five category scores on a 0-5 scale. Those five categories are weighted equally, averaged into one overall score, and then shown on property pages as a percentage out of 100.
Formula
Overall score per rating = `(Heating + Insulation + Ventilation + Draughtiness + Moisture) / 5`
Displayed score = `(overall score / 5) x 100`
The five categories in the score
ratemyflat aligns the score with the main Healthy Homes topics renters actually care about when comparing a flat in New Zealand.
Insulation
Uses inputs like glazing, curtains, ceiling insulation, wall insulation, and legacy insulation answers where needed.
Ventilation
Checks kitchen and bathroom extraction plus whether habitable rooms can be ventilated.
Draughtiness
Measures whether the home has unintentional gaps and noticeable draught issues.
Moisture
Includes indicators such as mould, condensation, drainage, and moisture-related conditions.
How one rating becomes one score
- Each answer is normalized to a score between 0 and 5.
- Questions inside a category use question-level weights.
- The weighted questions become a category score for that rating.
- The five category scores are combined using equal category weights of 20% each.
- The final value is stored on a 0-5 scale and displayed as a percentage.
How property-level scores are combined
A property can have more than one completed rating. When that happens, ratemyflat combines the stored scores from completed visible ratings to produce the property-level Healthy Homes Score shown on the listing.
Verified tenant ratings are weighted more heavily than unverified ratings. In the current calculation, verified ratings use a weight of `1.0` and unverified ratings use a weight of `0.7`.
The category breakdown shown on the property page is also aggregated with those same review weights.
What the score does and does not mean
The Healthy Homes Score is a practical comparison tool, not a legal compliance certificate. It is designed to help renters compare warmth, dryness, ventilation, and likely comfort across listings using the information currently available to ratemyflat.
Useful for
- Comparing two rentals quickly
- Understanding why one property scores better than another
- Spotting likely issues before you book a viewing or apply
Not a substitute for
- An official Healthy Homes assessment
- A landlord compliance statement
- Your own inspection of heating, ventilation, dampness, and obvious defects
FAQ
Common questions about Healthy Homes Scores
Why do some property pages show category details from one review?
The numeric score is aggregated across completed visible ratings, while some descriptive item details may come from a representative review so the page stays readable.
Why is the displayed score out of 100?
Internally the system stores Healthy Homes scores on a 0-5 scale. The property page converts that number to a percentage because it is easier to scan.
Can the formula change?
Yes. ratemyflat can refine question mappings or weights over time, but this page describes the current scoring approach used by the product today.
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