Which layout type allows for 4-8 lots per acre?

The alley layout is designed to promote land efficiency and flexibility, allowing for a higher density of lots, typically ranging from 4 to 8 lots per acre. This type of layout incorporates alleys, which are narrow passages that reduce the need for extensive street frontage for each lot. By shifting vehicle access to the rear via the alley, this arrangement can increase the number of lots within a limited area while also enabling more usable front yard space and promoting walkability. The design also has the potential to enhance communal space and reduce the visual impact of parked cars on the streetscape.

In contrast, the other layout types often either accommodate fewer lots per acre or serve different urban design objectives that do not inherently support the same density. For instance, grid layouts focus on systematic street patterns and might not maximize the number of lots, while deep narrow lot layouts generally result in longer, thinner plots that can lead to lower density. Z-lot layouts usually integrate varied lot shapes that prioritize aesthetics or specific land uses, which can also reduce the number of lots fit into an acre compared to an alley layout.