Montclair's listed office stock stands at 10 lots, all inside one building at 28 Valley Road. Concentration like that is normal for a commuter town: Montclair absorbs firms that want a professional address without a city-centre lease, and one managed Valley Road building with 10 units covers a spread of tenant sizes rather than a single niche.
The size range in Montclair is unusually wide for one address: 5 m² at the bottom, 520 m² at the top. A 520 m² space and a 5 m² room under the same roof mean a company can start small in Montclair and expand inside the same building relationship instead of reopening the search a year later.
Half of the Montclair lots are larger than 190 m² and half smaller, so 190 m² is the figure to plan against. At standard open-plan density, a 190 m² unit in Montclair seats roughly 20 people with a meeting room and a kitchen point — the band where a suburban office stops being an overflow room and becomes a working base.
Tenants comparing Montclair should test how the 10 lots actually divide: whether the 520 m² top space is offered whole or split, and whether two mid-sized units can be joined. In a market of one building, that flexibility rather than location decides whether Montclair works for a growing team.