Methodology

How we know what we say

This is the Halifax Developments Map's source-of-truth document. Everything on the platform — every parcel, every permit, every zone, every photo, every analytical claim — comes from somewhere. This page names every somewhere, tells you when it was last refreshed, says how confident we are in it, and tells you what we don't know.

If the platform tells you something and you want to verify it, this page is where you start.

Where the data comes from

The platform integrates roughly 80 data layers across municipal, provincial, federal, and editorial sources. The current full source list, with refresh cadence and confidence grade per source, follows.

Halifax Regional Municipality open data (primary spine)

HRM publishes its planning, permitting, and regulatory data through its ArcGIS Hub at data-hrm.hub.arcgis.com, with all 364 underlying services accessible programmatically at services2.arcgis.com/11XBiaBYA9Ep0yNJ/. The platform pulls 16 of these layers as its primary spine. Refresh happens automatically via a verify-then-fetch pipeline that catches schema drift the day it happens.

The full per-layer schema, field-level documentation, and field-by-field source priority for entity resolution is published in the platform's technical annex.

Provincial parcel data

Federal building data

Editorial and photographic sources

How confident are we in any given claim?

Every attribute on the platform carries a visible confidence grade. The grades, from highest to lowest:

• Verified. Sourced from HRM open data, matched across two or more independent sources, no conflicting observations. This is the default for regulatory data (zone, max height, heritage status) and for permit data once permits are issued.
• HRM-source, single observation. Sourced from HRM open data with no corroborating source. Reliable but unaudited.
• Editorial-source, corroborated. Sourced from a blog post, FB caption, or developer marketing page and agreeing with at least one HRM source. We promote these from "editorial" to "corroborated" once a higher-priority source confirms.
• Editorial-source, single-source. Sourced only from editorial. We mark these explicitly in the UI with a "single-source" tag. They're shown but flagged.
• Inferred. Derived rather than directly observed — for example, "current construction phase" derived from the most recent passed inspection of a known phase type. Inference logic is published per attribute.

The source-priority order, when multiple sources disagree, is:

1. HRM regulatory authority (zoning, max height, heritage, subdivision)
2. HRM permit applicant (permit-stage attributes)
3. Developer marketing site
4. HRM CMP PDF
5. Facebook caption (era-aware)
6. Contributor submission

Higher-priority sources win by default. The platform shows the priority-resolved value as the displayed value, with a "see source history" disclosure that reveals every observation across every source and date.

Time-versioning — silent revisions are surfaced, not hidden

Project attributes change over time. The Abraham was filed by WM Fares in 2023; the most recent HRM record associates the project with Commons View Holdings. The transition wasn't announced publicly. The platform stores both observations with their dates and shows the change as a visible timeline rather than overwriting the historical record silently.

Same logic applies to other attributes — proposed unit counts that get revised between DA and building permit, developer names that change mid-project, architects-of-record that get swapped, project names that get renamed. If an attribute has had more than one distinct value across the platform's observation history, you'll see a "previously: X (until date Y)" line in the per-project drawer. This is the difference between a database that silently propagates revisions and a database that tracks them honestly. We chose the latter.

What we don't know — honest limits

We are confident about the data we publish, including its limitations. Some genuine gaps:

• The customer-side post-issuance duration in PPLC_Permit_Processing_Times aggregates construction time and developer-side scheduling delay together. We can't currently separate "the building actually took 14 months" from "the building was done at month 10 but the final inspection wasn't called until month 14." We're working on a derivation from the inspection log that would distinguish these; for now, we report the aggregate and flag the ambiguity.
• The HAF draft re-zoning data was last republished by HRM in April 2024. If HRM amends the draft, the platform will reflect the amendment within 24 hours of HRM's republication, but the historical state of the draft between our snapshots is not stored.
• The 4,500-post DevelopmentsHFX Facebook archive does not have 100% coverage of every HRM project. It heavily covers the Halifax peninsula and active mid-rise/high-rise projects; coverage is thinner for single-detached, suburban, and Dartmouth/Bedford projects. The platform's photo timeline is correspondingly richer for some projects than others.
• Pre-2019 posts in the Facebook archive don't follow the structured-caption format. Our era-aware parser can extract project names but cannot reliably extract developer/builder/architect attribution from those posts. We mark this in the per-project source-history view.
• The CMP PDF corpus only covers projects that went through CMP review. Smaller projects (e.g., 4-unit residential under HAF) don't go through CMP, so for those projects we don't have an architect-of-record source. The platform doesn't display an architect for those projects, rather than guessing.
• Inspection-derived construction phase doesn't apply to projects without an active permit. A project still in the DA phase shows as "pre-construction" because there's no inspection log to derive from.

If you encounter a specific data quality issue on the platform — a wrong attribution, a missing photo, a zone misclassification — there's a "report a data issue" link on every parcel page. Reports are reviewed within a business week.

How the platform is refreshed

The data spine is rebuilt automatically by a set of workers that pull from each source on its native cadence (sub-daily, nightly, weekly, or as-needed). Each worker runs a schema-drift check before fetching — if the source has changed shape, the worker fails loud rather than silently writing wrong data. The current state of every worker (last successful run, last attempted run, current row count) is shown on the platform's system status page.

The relationship with HELIO Urban Development

The Halifax Developments Map is published by HELIO Urban Development, a computation-driven real estate development company in Halifax. The platform is free, public, and ad-free. The firm's revenue comes from developing projects for a fee — not from subscriptions, sponsored content, or paid placement on this platform.

This means a few things in practice:

• The platform is editorially independent. No developer pays for placement here. No developer's marketing claims override the data. If a project's HRM permit data conflicts with what the developer's marketing site says, the HRM data wins on the platform, with both shown for transparency.
• The platform does not advocate. We don't take positions on whether specific projects should be approved or denied. The platform is value-neutral on outcomes; it makes the data legible and lets readers form their own views.
• HELIO publishes analysis on top of the data, on a regular cadence, under the firm's byline. The data is the foundation; the analytical posts and quarterly reports are how HELIO does the analytical work it claims to do — in public.
• HELIO will work with you on Halifax development questions that this platform doesn't fully answer. That's the firm's actual business. See HELIO's services in HRM for how an engagement works and how to reach us.

Reference documents

• Technical annex — per-layer schema, field-by-field documentation
• Jackson Sourcing Investigation — per-field accuracy assessment of the DevelopmentsHFX archive and how we cross-corroborate
• HRM Data Source Survey — full enumeration of HRM's 364-service catalog and which 80 are development-relevant
• Editorial voice guide — how we write analytical posts and reports
• System status — live worker health and last-refresh times

Last updated: 2026-05-18. Methodology changes are version-controlled and historical versions are retained. If you find an error in this document or in the platform's data, please tell us — corrections are published within a business week.

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