Introduction - Living Roofs in Integrated Urban Water Systems - page 13

area of a large hydrological system, and must be intended to contribute to it or
mitigate negative human impacts on it.
1.5.2 Dynamic life-cycle
Living roofs are dynamic, living systems. Each roof's appearance and function
responds to change in climate and vegetative processes. Its success is predicated
on a well-researched understanding of climate, appropriate component speciica-
tion, and a maintenance regimen that responds to the needs of the design objec-
tives, client needs or expectations, and site biology. Extensive living roofs should
be expected to “live” for decades.
1.5.3 Artiicial landscape
Living roofs are an engineered, constructed system. Everything ranging from their
components and structure (what they are) to their utilitarian and experiential
function (what they do) must relect the timescales and physical scales in which
they operate. That is, plant and growing media selection must be made to match
climate conditions. Decisions with respect to form (e.g., intensive or extensive
living roof, landscape over structure, etc.) must best suit the desired social or
functional use and intended physical scale and typology (residential or commer-
cial, single-lot or multiple-occupant, etc.).
1.6 book methodology
Applying living roofs to the urban environment can be considered at multiple
scales: building lot, city block, city-wide, sewershed or watershed. This topic pri-
marily discusses the design and implementation of a living roof applied to a
single building lot. At this scale, a living roof likely has a signiicant effect on
stormwater management and the client or landscape architect has the most
inluence over the design than at any other scale.
This topic explains how to analyze, plan, apply and integrate technical and
non-technical aspects of living roofs. It does not speciically address policy instru-
ments. Throughout the topic, we aim to provide guidance for a living roof project
to ensure minimum levels (or better) of stormwater management are realized
based on current research. Design enhancements over and above minimum rec-
ommendations are discussed, which will likely have better outcomes, while creat-
ing aesthetically desirable living roofs. We hope this topic promotes meaningful
living roof implementation that contributes toward holistic urban water
management.
Chapter 2 offers insights into common regulatory drivers for urban stormwa-
ter runoff, and a technical perspective on how a living roof “works” to control
runoff. Detailed summaries of academic studies on the stormwater performance
of living roofs, and how design inluences performance, are presented.
Chapter 3 focuses on the planning process. It identiies the roles of various
stakeholders in any living roof project, highlights topics for stakeholder discussion,