We've recently completed the project at Bell Close, a new modular housing development for Bristol City Council located on a brownfield sloping site within close proximity to Southmead Hospital. Previously occupied by a number of single storey garage plots that have since been demolished, the new development involves the construction of nine 1-bed residential dwellings built over two floors, provision of car and cycle parking, refuse and recycling storage, and hard and soft landscaping.
The site is surrounded by residential properties on all sides and can be accessed either via a pedestrian footpath or by vehicle from the adjacent road, Bell Close. It is owned and managed by the council.
KEY FACTS
- Urban infill project on a brownfield site
- MMC & innovative solutions
- Fabric first approach and highly insulated SIP panels
- PVs & ASHP
- Stakeholder engagement
Tom Renhard
Cabinet Member for Housing Delivery and Homes, Bristol City Council
£2.7m
CONTRACT VALUE
41 WEEKS
CONTRACT DURATION
Customer
Bristol City Council
Architect
BDP Architects
Quantity Surveyor
RLB
Form of Contract
JCT D&B 2016
SUSTAINABILITY AND INNOVATIVE TECHNOLOGIES
New eco homes standing the test of time
The new highly sustainable and net zero homes were factory built, trialling innovative technologies and modern methods of construction (MMC). The homes are highly insulated for minimal heating requirements and include renewable energy with solar PV panels and air source heat pumps, resulting in minimal environmental impact and low running costs which make them very cost effective. The overall sustainability strategy on Bell Close reflects the principles of local sustainable development policy, in line with Bristol City Council’s core strategies.
The development at Bell Close mitigates against climate change by implementing passive and fabric first design measure to reduce overheating, with consideration of future weather files, and a drainage strategy accounting for future climate change.
9
ECO HOMES
56.88 t
CO2 savings
a year
80%
Reduction in
carbon dioxide
3 m3/h.m2 @ 50 Pa
Air permeability
0.13 W/m2k
U-value (Walls)
Passive design and energy efficiency considerations
The design incorporates passive design measures to reduce energy demand, and energy efficient mechanical and electrical services. All available renewable energy technologies were also considered. Air Source Heat Pumps (ASHPs) and photovoltaics were found to be the most feasible technology. The installed ASHPs will be meeting 100% of the heating loads. The combined ASHPs and 9 kWp of photovoltaics (1kWp per dwelling) will lead to a total carbon emissions reduction of 56.88 tonnes of CO2 savings a year which is equivalent to a 80% reduction in carbon dioxide across the whole development. An all-electric ASHP heating and hot water solution will enable the building to benefit from the decarbonisation of the grid.
Prefabrication and MMC
The design was based around a MMC and we opted for an off-site fabricated SIPS system. From the outset Beard engaged with Etopia, a SIP supplier, and discussed challenges on this residentially bound and constrained site. The constrained access posed the major challenge on this site which initially could only be accessed via a public footpath. This access needed widening as part of enabling works so that general and continued access for residents was possible.
We collaborated with Etopia and developed a suitable solution which directly responded to the specific needs of this site. The SIP panels were divided into smaller units that were delivered to site and transported onto site via forklift. In cooperation with the wider team, we were able to develop a Logistics Plan that satisfied all site conditions. It meant that all large parts of the new dwellings were built off-site before being delivered to site for assembly, minimising disruption to the neighbours.
