ByRight PGH

Sources

How the AI was used

• Claude extracted the use and dimensional tables for the encoded districts from saved ecode360 captures of Title Nine (docs/sources). The rows were checked against those captures during development and re-checked by automated audits; an independent practitioner validation is not complete.
• No model sits in the decision path. Every verdict, triage color, count and dollar figure comes from those tables, public data and arithmetic you can read in the code.
• Where a model rewrites text (the optional wording suggestion in the filing packet), it is labeled as unverified model output and never replaces the deterministic text.
• Ask ByRight (the search box) lets a model turn a question into filter and lever changes, each shown and undoable; the answer sentence is computed by the engine, never written by the model.

Green, Yellow, Red, Gray

• Green, passes the screen: the best home type passes the use-table, lot-size, width, site and cost-and-return checks, and the lot is recorded for sale. Fit and staff review remain.
• Yellow, needs review, relief, data or a shortfall: the first open item is named on the lot: an unknown, a staff approval or Zoning Board hearing, relief, a modeled shortfall, or a lot not for sale.
• Red, blocked: no small home type is permitted by the use table, or a FEMA flood zone on steep or undermined ground.
• Gray, not checked: the district is not encoded, so zoning was not evaluated.

Steep slope, undermining and flood are screening flags at the inventory point. A flag keeps a lot out of Green and is listed as an open item; it never changes a zoning verdict. None of the colors confirms a project is feasible.

Green means the lot passes this preliminary screen under the displayed assumptions: its best home type is allowed by the use table and lot-size standards; the Use, Lot size, Width and Site checks all pass (Use is Unknown when the City zoning map names a different district than the inventory at the lot's point, or none); Fit is not failing (setbacks, height and coverage are not modeled, so Fit is usually Not checked); Finance passes the cost-and-return screen; and the City records the lot as Available for Sale, not as a park, greenway or infrastructure-protection parcel and not as privately owned. Two open items do not block Green: Fit not checked, and required on-site parking not verified; both stay listed on the lot. Green is a candidate for staff review, not a determination that the lot can be built or offered for sale. The proposal screened on each lot is the allowed home type with the lowest modeled shortfall to the target return (the highest margin when more than one clears the screen), ties to fewer dwellings; on a lot under 25 ft the attached form replaces the detached house.

Comps and finance

• Dennis Steigerwalt, Housing Innovation Alliance

  hackathon SME channel, Sept 26, 2026: city single-family infill hard cost, "$200–$250/sf is a reasonable range"

• Tom Hardy, hackathon SME

  hackathon SME channel, Sept 26, 2026: city site costs "$25k–$50k" per single unit (water/sewer taps, grading, sidewalks, landscaping); vertical construction $325–$375/sf. $35,000 is a chosen allowance within Tom Hardy's $25k–$50k range (single unit); applied once per project as our assumption.

• No comps file loaded; finance is not assessed for any lot.

A lot that is short at today's prices is common for small infill, not a dead end. The shortfall is a screening number, not a subsidy award or an eligibility finding.

Further reading: Pro-Housing Pittsburgh, “You Can't Build That Here” series

Rule sets

Current code (Title Nine as of 2026-09-16)

Title Nine as published on ecode360 (code through 2026-09-16), including Ord. 10-2025 which set one minimum lot size per density subdistrict and removed lot-area-per-unit minimums.

If Bill 2025-1545 passes

The substitute bill (June 2, 2026, corrected July 24, 2026) allows up to two ADUs on any lot with a residential use without owner-occupancy and deletes minimum off-street parking; it does not change residential lot-size minimums or the residential use table.

Districts encoded (27)

Lots in any other district show as not evaluated.

Engine caveats

• Screening only. Verdicts come from encoded tables, not from the Zoning Administrator; overlays, setbacks, height, lot coverage, FAR outside LNC, steep-slope (§ 915) and riverfront/IPOD rules are not evaluated, so building fit is never established.
• A failed lot-size check needs relief: a dimensional variance, or the § 921.04 nonconforming-lot exception if the lot qualifies; zoning staff determine the path.
• Under current code an ADU is allowed only inside an ADU Overlay District (§ 912.08); the prototype has no overlay layer, so the house + ADU permission is unresolved (not prohibited) until staff confirm.
• Lot area comes from the City inventory. Frontage is parsed from the County legal description; approximate; a survey governs. When either is missing, the check is marked 'needs survey', does not change the verdict, and keeps the lot out of Green.
• Frontage is used as lot width for the § 911.04.A.69A 35 ft attached-unit test in R1D; the code measures Lot Width, which can differ from street frontage. With no frontage in the record, the attached-unit permission is unresolved (P if ≤ 35 ft, else S), not a Special Exception.
• Parking minimums are reported, not checked against lot geometry.
• H (Hillside) single-unit uses need Administrator Exception review under § 911.04.A.69(a); those site conditions are not encoded.
• § 903.03.E lists no minimum lot size for VH subdistricts; the engine treats VH as having none.

Limitations

• City of Pittsburgh only. Lots in other Allegheny County municipalities are out of scope.
• Setbacks, height, lot coverage, and overlay districts are not encoded. A survey and a zoning review are still needed.
• Steep slope, undermining and flood are screening flags at the inventory point. A flag keeps a lot out of Green and is listed as an open item; it never changes a zoning verdict.
• County land value is the 2012-base assessment, not a market price.
• Street frontage is parsed from the County legal description; approximate; a survey governs. A lot with no frontage in the record reads "Unknown · survey needed".
• The header counts lots, not homes. The five home types on a lot are alternatives, so lot × home-type combinations are not added up anywhere.
• No personal information is used or shown. Parcels come from the City's vacant-land inventory; a few records are marked Privately Owned.
• Rules decide. No verdict comes from a model.