This document details the Transect Zoning Model - a planning tool organizing settlements from natural areas (T1) to urban cores (T6). It defines the Pedestrian Shed as a quarter-mile radius (1,320 feet) representing a comfortable 5-minute walk. Neighborhood Density varies by location while maintaining 120-160 acre areas. The document explains Hybrid Development types that blend New Urbanism with conventional suburban elements, including problematic "snout houses" with protruding garages. This systematic approach helps planners create authentic, walkable communities with appropriate density transitions.

1. New urbanism
CT.LAKSHMANAN B.Arch.,M.C.P.
SRM SCHOOL OF ARCHITECTURE
Transect model - detailed zoning
Pedestrian Shed
Neighborhood Density
Hybrid Development

2. Transect Zoning
 The rural-to-urban transect is a planning tool that
organizes human settlement patterns along a continuum
from undeveloped natural areas to dense urban cores.
 Much in the same way that ecologists organize plant and
animal communities—classifying key characteristics of
habitat, maturity, and diversity—the transect, advanced a
decade ago, can help planners identify characteristics
and indicators that are relevant in categorizing
communities along different points of the rural-to-urban
continuum.

3.  It is composed of six “Transect Zones” or “T-Zones”:
• T1 Natural Zone—land that is undeveloped and largely in its wild state;
• T2 Rural Zone—sparsely settled lands in open or cultivated state;
• T3 Suburban Zone—low-density residential areas, adjacent to higher zones of
mixed use;
• T4 General Urban Zone—primarily residential urban fabric, but inclusive of mixed
uses;
• T5 Urban Center Zone—higher-density, mixed-use buildings that accommodate
retail, offices, rowhouses, and apartments; and
• T6 Urban Core Zone—highest density and height, with the greatest variety of uses,
and civic buildings of regional importance, typically found only in large towns and
cities.
 There is an additional category, Civic, that is an overlay zone applicable anywhere on the six standard
zones.

4.  Three categories (Sub-urban, General, and Center) follow
the natural internal structure of the neighborhood. The
Core is assigned to the intensification that occurs where
several neighborhoods conjoin, and the Rural is outside
the urbanized area.
 Each zone is an immersive environment, a place where all
the component elements reinforce one another to create
and intensify a specific urban character. Several such
immersive environments within a single neighborhood
provide variegation, in contrast to the homogenous locales
of conventional suburbia.

6. Pedestrian Shed:
 a determinant of urban size, defined as the
distance that may be covered by a five-
minute walk at an easy pace from the outer
limit of the neighborhood proper to the edge
of the neighborhood center.
 This is the distance that most persons will
walk rather than drive, provided that the
environment is pedestrian-friendly.

7.  The pedestrian shed is conventionally one quarter of
a mile or 1,320 feet. By variance, this dimension may
be adjusted to accommodate site conditions:
 1. For TNDs of low density, by extension to a median
distance of a half-mile or 2,640 feet (this in order to
increase the population catchment).
 2. For TNDs having an eccentrically located center, by
calculating an average of the various edge-to-center
distances.

8. Neighborhood Density
 Neighborhoods are quantified by area, which is a
constant, rather than density, which must vary according
to the local market.
 A New England village may be 4 units/acre, while a New
York City neighborhood approaches 200 units/acre.
 A traditional neighborhood is defined by the area
generally circumscribed by a quarter-mile radius, which
is between 120 and 160 acres.

9. Hybrid Development
 A development in which an evolution towards a more complete TND
pattern is resisted rather than enabled by the original design, and
which is ultimately incapable of achieving a unified community.
 Blended Hybrid: a pervasive blend of conventional and NU
elements, such as sidewalks and porches, but on cul-de-sacs. It may
also take the form of a modified thoroughfare grid with front-loaded
snout-houses. A blended hybrid may or may not be able to evolve
over time.
 Smorgasbord Hybrid: a hybrid development with pods of
acceptable or even good New Urbanism, side-by-side with pods of
typical CSD (conventional suburban development)
 A snout house is a house with a protruding garage that takes up most of the street frontage