Planning considerations - Living Roofs in Integrated Urban Water Systems - page 54

drains can inluence stormwater mitigation performance, thus a hydrologic
engineer should also be consulted if stormwater management is a design
objective (it is noted that the presence of the living roof does not reduce a
requirement for roof drains).
• Allocating responsibility for planning approval. The contract will stipulate who
will oversee that the project complies with, for example, local living roof poli-
cies; health, safety and ire regulations; stormwater policies; local ecological
policies (e.g., biosecurity issues or protections), and policy available for the
building of living roofs. Local codes and by-laws often require stormwater to
be either mitigated on-site or be temporarily detained to reduce the burden
on the existing sewer/stormwater system or local receiving waters. For this sit-
uation, the design consultant team should apply a set of stormwater calcula-
tions to estimate if the living roof complies with these local by-laws. These
calculations may be required by local authorities to receive planning permis-
sion for the proposed design.
• Assigning responsiblity for overseeing installation of extra roof equipment and
technology. For example, cistern installation for artiicial irrigation has to be
coordinated by the architect, structural and mechanical engineer, and land-
scape architect, as they will determine the location of the cistern in or on the
building. The requirements of any renewable energy systems should be inte-
grated into the contract to achieve minimum footing dimensions, appropriate
infrastructure protection, and minimum additional loads on the living roof.
3.2.2 Tasks at the construction management planning table
The second set of discussions occurs around the construction management table
( Figure 3.2 ). They will revolve around tasks including project supervision and
drawing approvals. These discussions and tasks are taken on by design and
construction professionals, and sometimes the client, and include to:
• Deine overall supervision tasks to ensure that all planning tasks are accounted
for. Tasks are overseen by the on-site project manager, who coordinates all
professionals at this stage. For example, the on-site project manager ensures
that the designed perforations (drain locations and roof vents) are carried out
to speciications and are proven to be watertight before a living roof is
installed.
• Decide how and who is supervising the site. Overall, the on- site project
manager supervises the project. Work onsite must also be regularly inspected
by the architects, engineers and landscape architects, and records of site
inspections must be documented. The design consultants will also perform
regular site inspections during all stages of construction. The integrity of the
waterprooing membrane, especially, requires supervision of multiple
professionals (see Chapter 4 regarding methods of testing waterprooing).
• Approve working drawings and speciications. Before construction can begin,
landscape contractors need to review the design consultant-designed and