A noise data field, or a noise calculation? They’re not the same thing.
Homedata’s own site describes its noise field as “Defra road and rail noise zones” — a government zone label, looked up for about a penny a call, one line among dozens of unrelated property-risk flags. AcoustaPLOT’s Noise Risk Screening is a calculated result for the specific property, with a stated accuracy range and a named standard behind every figure. Here’s exactly what that difference is, with nothing asserted that isn’t checked against both companies’ own published material.
What you actually get, and what it costs
| Homedata’s noise field | AcoustaPLOT Noise Risk Screening | |
|---|---|---|
| What the noise field actually is | A Defra road/rail noise zone, looked up for the location (their own site's description) | A calculated Lden/Lnight figure in dB, using Defra where it has coverage and CRTN 1988 + real DfT traffic data where it doesn't |
| What you're shown | A zone label — one of several property-risk flags in a general due-diligence bundle | A numeric result, a 7-band risk rating, the dominant source named, and a stated accuracy range |
| Road + rail both present | Not stated as a combined figure | Combined correctly by logarithmic energy addition into one overall exposure |
| Price | 1 token per call (100 tokens = £1) — about 1p | £34.99 (Noise Risk Screening) |
| Tells you what to do about a problem | No — it's a data field, not an assessment product | Yes — Acoustic Barrier Design (£349) models a real fence to ISO 9613-2 and recommends a height |
| Escalation path if Screening isn't enough | None at any price | Insight (£99) → Barrier Design (£349) → Complete Report (£499) → Whole-Site Study (£750) |
Homedata figures per their own published site, checked 7 October 2026. AcoustaPLOT figures per our own methodology and pricing pages.
We use Defra’s data too. That’s not the difference.
It would be misleading to imply AcoustaPLOT never touches Defra’s Strategic Noise Maps — it does, as a primary source wherever they have coverage for a property. The real difference is what happens with that starting point, not whether it gets used at all.
Where Defra has coverage, AcoustaPLOT converts the banded result into an actual Lden and Lnight figure, states an explicit accuracy range on every result, names the dominant source, and combines road and rail exposure correctly when both apply. Where Defra has no coverage — and, as our own guide to reading a Defra noise map explains, coverage is a real limitation of the national maps, not a detail specific to any one reseller of them — AcoustaPLOT doesn’t return a blank. It calculates the level directly, using the UK’s Calculation of Road Traffic Noise (CRTN, 1988) method applied to real Department for Transport traffic-count data for that road.
A tool that only ever passes a government zone label straight through can only ever be as current, as precise, and as complete as that underlying map — because that map is all it has to work with.
The price gap reflects a different product, not just a markup
£34.99 against roughly 1p is a real gap, and it’s a fair question to ask why. The honest answer: a calculated, standards-referenced figure with a stated accuracy range costs more to produce than passing a government label through — and Screening is also the entry point to a ladder a bare data field has no equivalent of at any price. Need more than a screening flag? A £99 Insight Report goes deeper on the same property; a £349 Acoustic Barrier Design physically models a real garden fence to ISO 9613-2 and recommends an actual height; a £499 Complete Property Noise Report and a £750 Whole-Site Desktop Study take it further still, for one property or a whole development.
A property-data API answers “is there a flagged noise zone here?” as one line among dozens of unrelated checks. AcoustaPLOT answers “what is the noise level at this specific property, how confident are we, and — if it’s a problem — what do I do about it?” Which one is better value depends entirely on which of those two questions you’re actually asking — and for a quick first-pass flag across a large portfolio, a cheap data-only field is often the right tool, which is why our own bulk address-checking tool offers a comparable data-only tier too.
See the calculation for your own property.