Oct 25, 2019
Set out below are perhaps the most serious and obvious sustainability
criticisms of the THAT Group planning application for the WH Smith site in
the heart of Clifton.
The scheme fails to achieve a BREEAM 'Excellent' rating (BCS 13). The
report actually states that they are unable to do so with this design.
They argue to be allowed to use BREEAM 2014 rather than the current version
BREEAM 2018 (as the design is in effect obsolete).
The scheme reduces carbon emissions from residual energy use by only
14% (20% required BCS 14). Only token renewable energy generation is
proposed. The main energy source is electricity from the National Grid
which is currently generated 65% from carbon sources (Gas and Coal fired
power stations with massive transmission losses).
Measures to substantially reduce carbon emissions from energy use are
the absolute minimum necessary to comply with Part L of the Building
Regulations. Passivhaus standards would necessitate thermal insulation U
values approximately 1000% higher.
The proposal makes no provisions or contribution for public
transport, bicycles or electric vehicles. Massive additional parking would
be inflicted on Clifton Village and on the local neighbourhoods especially
at weekends when residents parking permits are not required.
The proposals make no meaningful contributions to biodiversity and does
not create place/s with trees for people as the alternative community
Sustainability has clearly not informed the design and construction of
Architecture & Planning
Redevelopment Proposal of 2 - 16 Clifton Down Road by THAT Group
Technical Review of Energy and Sustainability Statement ( 16 July 2019 )
21 November 2019
Non-Compliance with Bristol Development Framework Core Strategy June 2011
Policy BCS13 (Climate Change)
13.1Development should mitigate climate change through measures including:
High standards of energy efficiency including optimal levels of thermal insulation, passive ventilation and cooling, passive solar design, and the efficient use of natural resources in new buildings.
It is immediately apparent that:
a.The standard of energy efficiency is not ‘high’ eg Passivhaus standard. The standard is the minimum necessary to comply with current Building Regulations and will therefore fail to contribute to BCC’s target of 80% reduction in carbon emission by 2050. No evidence has been submitted to indicate that the proposals represent at least a 80% reduction in carbon emissions compared with the existing building.
b.The levels of thermal insulation are not ‘optimal’.
The U values proposed are: wall 0.30 W/m2K, floor 0.25 W/m2K, Roof 0.20 W/m2K, glazing (window and doors) 2.00 W/m2K. The proposed U value are far from ‘optimal’ (see 14.1 below ).
c.Mechanical not passive ventilation is proposed.
d.Air conditioning is proposed not passive cooling
e.The design is not a passive solar design. Massive uncontrolled solar gains will necessitate high energy cooling.
f.The use of natural resources is not efficient. No recycled or natural materials are proposed for the fabric.
13.2The use of decentralised, renewable and low-carbon energy supply systems.
The primary energy supply system will be the National Grid. Currently, only 35.8% of UK electricity is generated from renewables ( Q1 2019 ).
13.3The development makes no special provisions for walkers, cyclist and bicycles, nor waiting facilities for buses and taxis. The development provided no parking facilities for electric (or other sustainable energy powered vehicles eg hydrogen).
it is anticipated that the scheme will create considerable (as yet unquantified) car parking demand in Clifton village and surrounding residential areas where the controlled parking only applies mid week and not at weekends when shopping parking demand will be greatest).
13.4The design and construction do not exhibit ‘resilience to climate change’.
13.6Unlike the local community’s proposals, green infrastructure is not used to minimise and mitigate heating of the urban environment.
The applicant’s Sustainability Statement is required to demonstrate measures to mitigate and adapt to climate change and meet CO2 targets. BCS13 requires that ‘statements should set out a comprehensive approach to mitigating and adapting to climate change which, in addition to the use of renewable and low-carbon energy (Policy BCS14), the use of sustainable design and construction measures (Policy BCS15), and a response to the risk of flooding (Policy BCS16), should include measures to adapt to the effects of climate change’.
The applicant’s Sustainability Statement ( Paul Weston of Box Twenty dated 16 July 2019 ) fails to demonstrate any significant measures to mitigate and adapt to climate change and meet CO2 targets, save table 1 which indicates that the residual energy demand and emissions ( 14 % row 3 ) falls significantly short of the Policy Requirement ( 20% ).
The report presents results from a BREEAM 2014 assessment only. The report states that ‘ the project team have reviewed the design and (concluded that) BREEAM cannot be achieved.’ (Section 7. BREEAM Assessment page 8 ). The proposals are therefore incapable of reaching BREEAM 2018 excellent standard.
The current BREEAM standard is BREEAM 2018: it was published on 7 March 2018 over 20 months ago. It is our contention that this proposal should comply with BREEAM 2018 Outstanding Standard (> 85% )or the entire building ( ‘shell and core’ and not merely the ‘core’) and must comply with at least BREEAM 2018 Excellent Standard (70%) for the entire building ( ‘shell and core’ ) and not merely the ‘core’.
Policy BCS14 (Sustainable Energy)
Development should include measures to reduce carbon dioxide emissions from energy use in accordance with the following energy hierarchy’:
14.1 Minimising energy requirements The proposal merely attains the level of the current Building Regulation ‘deemed to satisfy’ standards.
The Passivhaus system is designed to achieve minimal energy losses and minimal energy inputs.
A comparison between the insulation standards of the THAT scheme with the Passivhaus standards are set out below.
THAT schemePassivhaus Standard
Solid Wall0.30 W/m2K0.10 - 0.15 W/m2
Glazed Wall2.00 W/m2K0.10 - 0.15 W/m2
Floor0.25 W/m2K0.10 - 0.15 W/m2
Roof0.20 W/m2K0.10 - 0.15 W/m2
In the design proposal, the glazed walling represents some 60% of the total external wall. The average U value of the vertical envelope (the external wall) of the building is therefore U = 1.32 W/m2K whereas the average U value for a Passivhaus scheme (as the current RIBA award scheme in Norwich) would be between 0.1 and 015 W/m2K. The approximate Passivhaus thermal insulation standard represents an improved standard of about 1000% (880% better U =- 0.1 W/m2K and 1300% better U = 0.1 W/m2K ).
14.2 Incorporating renewable energy sources
BCS 14 states that ‘development will be expected to provide sufficient renewable energy generation to reduce carbon dioxide emissions from residual energy use in the buildings by at least 20%. An exception will only be made in the case where a development is appropriate and necessary but where it is demonstrated that meeting the required standard would not be feasible or viable.’
The development is not considered to to be ‘necessary’. It is not accepted that the required standard is un-feasible nor not ‘viable’. The exclusion of renewable CHP / CCHP has not been conclusively demonstrated.
14.3 Incorporating low carbon energy sources: the primary energy source proposed is on-peak electricity from the National Grid. At present, renewable energy represents approximately 35% of the total energy generation. Thus 65% of the energy used will be from non renewable sources ( principally gas and coal ).
The proportion of low carbon energy is therefore small (approximately 30% only).
Policy BCS15 (Sustainable Design and Construction)
The aim of this policy is to ensure new developments are designed and constructed to minimise their environmental impact, and contribute to meeting targets for reductions in carbon dioxide (CO2) emissions.
15.1 Maximising energy efficiency and integrating the use of renewable and low carbon energy. The energy efficiency of the proposal is derisory: it falls short by approximately 1000% of the intention to maximise energy efficiency. Vestigial and minimal use is made of the use of renewables and low carbon energy.
15.2Waste and recycling during construction and in operation: the sustainability report makes no proposals at all.
15.3The type, life cycle and source of materials to be used: the sustainability report makes no proposals at all.
15.4Flexibility and adaptability: the sustainability report makes no proposals at all
15.5Opportunities to incorporate measures which enhance biodiversity value of the development, such as green roofs: The proposal does not propose green roofs nor green walls. Whereas minimal planting of small trees is proposed, the unwarranted felling of the existing site tree/s is proposed. The opportunity to create a major new public open space with an avenue of trees as proposed by the local community has not been grasped let alone realised.