578 avenue Roslyn vs 646 avenue Roslyn
Data as of October 29, 2026 · updated every week
646 avenue Roslyn is the older building (1908); 578 avenue Roslyn was built in 1911. 578 avenue Roslyn is assessed at $3,266,300, 61% more than 646 avenue Roslyn ($2,022,500). Neither has a building permit on record. Neither is in a flood zone.
| 578 avenue Roslyn | 646 avenue Roslyn | |
|---|---|---|
| Type | House or building | House or building |
| City and borough | Westmount | Westmount |
| Built | 1911 | 1908 |
| Assessed (roll) | $3,266,300 | $2,022,500 |
| Since the previous roll | 0 % | 0 % |
| Welcome tax on that value | ≈ $47,105 | ≈ $28,448 |
| Lot | 516 m² | 387 m² |
| Floor area | 290 m² | 246 m² |
| Notice of deterioration | No | No |
| City’s right of first refusal | No | No |
| Heritage | No | No |
| In a flood zone | No | No |
| Building permits on record | 0 | 0 |
| Findings | 1 Note | 1 Note |
| Nearest metro | Villa-Maria, 960 m | Villa-Maria, 840 m |
The full report for each address explains every finding and shows the full permit and value history.
Full report: 578 avenue Roslyn Full report: 646 avenue Roslyn