1-3 Westbourne Grove Energy Statement Incorporating Sustainable Construction

Scope of Project: Energy Statement Project Incorporating Sustainable Construction

Sustain Quality were instructed to provide an Energy Statement incorporating sustainable construction and implementing energy efficiency measured initiatives, including to, ‘be Green’ and ‘be Lean,’ looking at installation of ASHP (Air Source Heat Pumps) and utilising high performing insulating materials within the overall energy strategy.

The proposed Westbourne Grove development, located within the Westbourne Conservation Area, was a façade retention scheme which included a pub/restaurant on the basement and ground floor with four residential units from the first to fourth floor. Although the site project was within Westbourne Conservation Area, it is not a listed building or recognised as an unlisted building of merit in the Conservation Area Audit.

The project strived towards sustainable development in accordance to the UK Sustainable Development Strategy, 5 guiding principles of sustainable development, and best practice measures were adopted, as well as, the Energy Hierarchy facilitation (of be Lean, be Clean and be Green) during the proposed design and resulting CO₂ savings in accordance with local and national planning policy.

Energy Statement Tools for Implementation

We completed an energy assessment with aspects of sustainability integrated within the report. We utilised SAP (Standard Assessment Procedure) models for the residential units and SBEM (Simplified Building Energy Model) models for the commercial bar space. These models are calculation tools that utilise software, where SAP looks at overall energy used and SBEM generates the energy performance calculation (EPC) rating used for the purposes of compliance for Part L of the Building Regulations.

 Policy Target

Utilising The Energy Hierarchy, an energy assessment was carried out and integrated into the report with the identified target, as set out in the London Plan policy S12 and the City of Westminster’s policy 36, being that residential development is required to achieve 10% minimum on-site reduction beyond Building Regulations, whereas non-residential development needs to achieve 15% through energy efficiency measures.

The Energy Hierarchy 

Adopted throughout and set out within a report, using the Energy Hierarchy, a ‘best practice’ approach was sought. Reducing carbon emissions through the implementation of:

• Energy demand reductions of ‘be Lean’, including high performance insulating materials;
• Plus, ‘be Green’ was also used as part of the energy strategy with the installation of Air Source Heat Pumps (ASHPs).

Be Lean

Energy efficiency was measured first to assess the capacity to reduce energy demand. These measures were used and incorporated into the design through the use of high-performance insulating materials that improved the U-values of fabric elements, thermally efficient glazing and lighting as well as heating controls.

The upgrades were predicted to provide 20% CO₂ reduction site-wide compared to Part L 2021 Baseline.

Be Clean

It was assessed and considered at this stage, whether CHP systems (combined heat and power) could be supported. Looking at connection to an existing or planned heat network was analysed, however, the feasibility of using this as a part of the energy strategy was excluded at this time due to the distance to the site and scale of the site.

Be Green

The consideration of various Low and Zero Carbon (LZC) technologies were analysed as part of the design process for this proposed development, with the resulting recommendations being an air to water, Air Source Heat Pump (ASHP), to provide space and water heating respectively.

The proposed LZC upgrades are predicted to achieve a further CO₂ of 51% site-wide compared to the Part L 2021 Baseline.

Energy Demand: Working out The Part L Baseline

The baseline was calculated to assess the proposed development against the relevant planning criteria and the first part of the assessment was to ascertain the baseline for energy consumption and related emissions.

DesignSAP10 modelling software was used to determine Part L 2021 compliance. Models were then used at each stage of the Energy Hierarchy and input into a Greater London Authority’s Carbon Reporting spreadsheet to confirm the reduction in CO₂ at each stage.

Sustainable Design

In order to achieve environmental sustainability within the development, the energy strategy proposed by the developer was consulted. In addition to this, aspects such as site management and handover under the Considerate Constructors Scheme, transport and water efficiency strategy were evaluated to ensure the development aligned with the Sustainable Development Goals (SDGs).

Key Project Achievements

Using, ‘be Lean’ and ‘be Green’ combined measures, from the adopted energy strategy, the proposed development is predicted to deliver a total cumulative CO₂ emissions savings of 71% site-wide in comparison to the Part L Baseline (76% in residential units and 49% in commercial units).

The proposed development of Westbourne Grove also exceed the requirements of the London Plan policy S12 and the City of Westminster policy 36.

Benefits for Clients

The project is committed to sustainable development (aligning with Sustainable Development Goals (SDGs)) and future sustainable requirements, where closely guided adherence is administered.

The Energy Assessment for Westbourne Grove development provided opportunity for the development to reduce cumulative emissions and to improve the buildings energy efficiency utilising reliable metrics to track, understand and record data. Accredited assessors were able to accurately analyse the information, enabling performance goals to then be set and implemented, promoting the three pillars of importance: Economic, Environmental and Social but also translating into People, Planet and Profit.

The advantages of this project are not solely reserved for the development itself but also importantly consider the responsibility of the development and its stakeholders, to maintain sustainability, whilst additionally protecting minimal impact to the environment along with providing economic benefits and the benefits to society (those living close by and those using it).

Location

1-3 Westbourne Grove, London, W11 2RU