Data Sources
We combine data from multiple verified sources to create comprehensive installer profiles:
Multi-Platform Reviews
We aggregate ratings from 25+ review platforms including Google, Trustpilot, Checkatrade, Which? Trusted Traders, TrustATrader, Bark, and more. Each platform is weighted by credibility to produce a fair overall rating.
Verification frequency:
Verified during enrichmentData fields:
Google Business Profile
Ratings and reviews pulled directly from Google Business Profile via the Google Places API. Google reviews are attributed with a link to the original source and weighted as a Tier 1 (full credibility) platform.
Verification frequency:
Synced during profile enrichmentData fields:
MCS Certification Registry
https://mcscertified.comCertification status, numbers, and validity dates verified against the official MCS database. We provide direct verification links to the MCS registry for transparency.
Verification frequency:
Verified during enrichmentData fields:
Multi-Platform Presence Discovery
We discover and verify installer profiles across 25+ platforms using search queries and HTML verification. Company names are checked against page content — titles, headings, and metadata — to prevent false matches.
Verification frequency:
Checked periodicallyData fields:
Installer-Provided Data
Business information provided by verified installer accounts and cross-referenced where possible. Installers can claim their listings to update this information directly.
Verification frequency:
On claim submissionData fields:
Public Registries
Company information verified against Companies House and other public business registries to ensure accuracy of business details.
Verification frequency:
Verified during enrichmentData fields:
How Our Rating System Works
Instead of simply averaging star ratings, we use a Bayesian-weighted system that accounts for platform credibility and sample size. This means installers are rated fairly regardless of which platforms their reviews come from.
Platform Credibility Tiers
Not all review platforms are equally trustworthy. We assign credibility weights based on how independently reviews are collected and verified:
| Tier | Weight | Platforms | Why |
|---|---|---|---|
| Tier 1 | Full weight (100%) | Google, Trustpilot, Checkatrade, Which? | Installers cannot delete negative reviews; reviewers are identity-verified |
| Tier 2 | 80% weight | TrustATrader, Bark, Facebook, MyBuilder, Yell, FreeIndex, and others | Independent platforms with some editorial control over reviews |
| Tier 3 | 50% weight | Website testimonials | Self-selected by the installer — positive reviews are naturally over-represented |
Statistical Fairness
A perfect 5.0 from 5 website testimonials is not the same as a 4.8 from 200 Google reviews. Our Bayesian system accounts for this:
- Small sample sizes are pulled toward the site-wide average, preventing a handful of reviews from producing an inflated score
- More reviews from trusted platforms means the rating more accurately reflects actual performance
- Installers with many independent reviews earn higher confidence ratings than those relying on website testimonials alone
Rating Labels
Each installer earns a label based on their Bayesian-weighted rating, effective review count, and how many independent platforms they have reviews on:
| Label | Rating | Requirements |
|---|---|---|
| Exceptional | 4.8+ | 25+ effective reviews from 2+ independent platforms |
| Excellent | 4.5+ | 10+ effective reviews from 1+ independent platform |
| Very Good | 4.0+ | 5+ effective reviews |
| Good | 3.5+ | 3+ effective reviews |
| Average | Below 3.5 | 3+ effective reviews |
| Not Yet Rated | — | Fewer than 3 effective reviews |
Honest Language
We are careful about how we describe reviews:
- Reviews from independent platforms (Google, Trustpilot, Checkatrade, etc.) are labeled “verified reviews”
- Website-only testimonials are labeled “customer reviews” — never “verified”
- A company’s own website is never counted as a “trusted platform” in rating thresholds
Data Freshness
Each installer profile shows when data was last verified. Here is how each data type is kept current:
- Google Reviews: Synced during profile enrichment via Google Places API
- Platform Presence: Discovered and verified periodically via search
- Certifications: Verified during profile enrichment against MCS registry
- Business Information: Updated when installers claim and manage their listings
Transparency & Attribution
We believe in complete transparency about our data sources:
Reviews from independent platforms are labeled “verified” — website testimonials are labeled “customer reviews”
Platform credibility weights are reflected in the overall rating
All reviews link to their original source platform
MCS certifications include verification links to the official MCS registry
Each profile shows where data was last sourced
See Incorrect Information?
If you're an installer and notice outdated or incorrect data on your profile, you can claim your listing to update it directly. For other corrections, please contact us.
Why This Matters
Most comparison sites show a single star rating with no context about where it comes from. We take a different approach: every rating is weighted by platform credibility, adjusted for sample size using Bayesian statistics, and clearly labeled with the source. This means an installer with 200 verified Google reviews is fairly compared against one with 5 website testimonials — and you can see exactly how each rating was calculated.