COMHAIRLE CONTAE ÁTHA CLIATH THEAS
SOUTH DUBLIN COUNTY COUNCIL

South Dublin County Council Crest

MEETING OF SDZ, LAPS AND PLANNING PROJECTS

Friday, January 26, 2018

MOTION NO. 214

MOTION: Councillor P. Gogarty

In Section 2.8 Built Form and Design under heading Roofscapes, amend to read as follows:

A variety of roofscapes are encouraged to contribute to the architectural
and visual diversity of the SDZ Lands and the quality of streets and
spaces. An additional set-back floor above the maximum permissible
storey height will be considered where it is shown to make a positive
contribution to the streetscape via a Design Statement and where there
are no adverse effects on amenity, such as an unacceptable loss of

daylight or sunlight.

All roofs should have sufficient southerly orientation so as to allow for the efficient installation of Solar PV units.

All apartment block, landmark building and retail roof spaces shall incorporate at least 50% Green Roof technology so as to minimise the effects of flash flooding caused by heavy rainfall.

Cllrs G. O'Connell, L. O'Toole and F. Timmons

REPORT:

This motion relates to Roofscapes within Section 2.8.6 Building Heights and Street Widths. 

It is considered that the roofscape orientation for any particular building will be decided on a case by case basis and should be considered at detailed design stage in conjunction with planning applications for development on the SDZ lands. Having regard to the motion submitted it is considered that the Planning Scheme should promote southerly orientations to encourage the installation of solar technology on roofscapes. The wording of the proposed motion should be amended accordingly, as follows: 

The Planning Schemes promotes southerly orientation of roofscapes to maximize the potential for solar technology installations on roofscapes within the SDZ.

The inclusion of green roofs in new developments can make significant contributions to managing and draining surface water in an environmentally friendly way, and as part of Sustainable Urban Drainage Systems (SuDS).  In this regard Section 2.9.5 of the Draft Planning Scheme states, ‘Roof water runoff should be captured and treated within the curtilage of each site, for example through use of Blue and/or Green Roofs. Such measures should be prioritised for larger/mixed use developments within the Kishoge and Clonburris urban centres’. 

In consideration of the motion wording ‘All apartment block, landmark building and retail roof spaces shall incorporate at least 50% Green Roof technology so as to minimise the effects of flash flooding caused by heavy rainfall’, such a mandatory requirement will impact on the viability and effectiveness of rainwater harvesting systems for apartment, landmark buildings, retail buildings and other high density mixed use developments. The use of green roof measures may, therefore, not be appropriate or viable for all developments on the SDZ lands.

Furthermore, in accordance with Section 2.9.5 of the Draft Planning Scheme, it is considered that there are a range of options for flood alleviation for each development proposal and on a case by case basis. It is considered that to ensure that

all apartment block, landmark building and retail roof spaces shall incorporate at least 50% Green Roof technology, is overly prescriptive and may limit the range of flood alleviation and climate change adaptation measures that are both viable and practical on each site. 

Having regard to the Government’s commitment to addressing the need for new residential development in Ireland and the implementation of ‘Rebuilding Ireland’ (2016), it is considered that the viability of new development and residential supply on the SDZ lands, would be placed at risk by insertion of unreasonable or excessive requirements in relation to the standard of housing or ancillary services and facilities that, in turn, impact adversely on the economic viability of commercial investment in and deliverability of new housing development over the lifetime of the SDZ Planning Scheme. 

Having regard to mitigation of the risk of flooding by all apartment block, landmark building and retail roof spaces incorporating at least 50% Green Roof technology, it is considered that this proposed wording should be amended as follows:

To mitigate the risk of flooding the Planning Scheme promotes the use of Green Roof measures in accordance with Section 2.9.5 (Surface Water Drainage and Sustainable Urban Drainage Systems).

 

Recommendation

It is recommended that this motion is adopted with amendment. 

Add additional text to Section 2.8.6 (Roofscapes) as follows:

The Planning Schemes promotes southerly orientation of roofscapes to maximize the potential for solar technology installations on roofscapes within the SDZ.

To mitigate the risk of flooding the Planning Scheme promotes the use of Green Roof measures in accordance with Section 2.9.5 (Surface Water Drainage and Sustainable Urban Drainage Systems).

 

Strategic Environmental Assessment of Chief Executive’s Recommendation

Positive effects identified for climate change and green infrastructure SEOs in particular.

Appropriate Assessment Screening of Chief Executive’s Recommendation

No likely significant effects on European sites within the SDZ’s zone of influence are predicted.