Scheme Summary

The scheme comprises 5 three bed family houses and 9 cottages for smaller households. It is a comprehensive approach to develop a sustainable community and was completed in 1999.


Scheme Details

The scheme aimed to develop sustainable housing that addresses the constraints and realities of social housing. Initially consideration was given to testing technologies in an individual house. It was quickly recognised that a whole estate needed to be built if the scheme was to have a positive and lasting contribution.

The homes were built on a derelict brownfield site close to existing facilities and communities.

The scheme was designed to address residents' concerns on space standards, neighbourhood security and heating and water costs. It also addresses ecological and comfort and health issues. Extensive monitoring measures are included to enable benefits to be assessed.


Environmental Features

The negative environmental impacts of the houses were significantly reduced through design, construction, and material use. The timber framed homes have high levels of insulation. The roof insulation has a depth of 350mm which is reflected in the design of the roof. The overall insulation achieved a U value of 0.19W/m2C. The double glazed, low emissivity coated windows complement the insulation with U values of 1.90 W/m2C. Three ventilation systems were installed throughout the development and are being monitored for effectiveness. These are:

  • full mechanical ventilation with heat recovery
  • standard mechanical extract ventilation
  • passive stack ventilation

Standard gas boilers were installed with an intelligent control system. The system is easy to use and optimises performance by monitoring ambient temperatures.

Low volume WCs, flow restrictor taps and water butts will reduce mains water consumption and make resident cost savings. Initial plans included the use of a rainwater recycling system for WC flushing to further reduce the need to use mains water. However, health concerns and statutory requirements could not be overcome within the allocated budget and the system was not installed.

The buildings have been designed and orientated to maximise passive solar gain (faced within 25° of south). Flat plate solar collectors pre-heat hot water, which could meet up to 60% of household demand.

Photovoltaic roof tiles that co-ordinate with the normal roof tiles are installed for one home. The energy produced from daylight is used directly by the house to meet some of its energy demands. Any surplus is fed to the National Grid.

Recycling and reuse of materials was also important. Cellulose insulation, reclaimed bricks and timber, recycled stone and hardcore for infill and the use of waste wood for I beams of the timber structure all assisted in reducing the environmental impact of construction. Over 50% of the walls and floors are constructed with recycled materials.

Two different insulating techniques were adopted. Twelve homes had cellulose (recycled newspaper) blown in between wall and floor I beams on site. Two others were constructed from fully insulated pre-fabricated panels.

The development went beyond a sustainable building fabric and considered site and lifestyle issues. An ecological assessment of the site established the natural features to be retained, and identified the types of planting to be introduced to enhance the existing ecological value.

Multiple storage containers are provided to encourage the separation of household waste for recycling. A manual was given to all residents promoting the use of energy efficient appliances.

To accommodate residents throughout their lifetime, the properties are built with wide doorsets, level access, comfortable pitch of stairway, accessible sockets, space standards in excess of Paker Morris, non load bearing partitions, and the opportunity for shower installation at ground floor.


Costs

The development considered construction cost, replicability and cost reduction in use. The footprint and site layout provided affordable densities. The building specification of high quality, durable materials with high insulation and energy efficiency features all help to reduce tenant running costs.

The scheme cost in the region of 20% more than a standard build. It needs to be noted that the scheme was used to explore and test new techniques and technologies that could improve environmental performance of housing. The higher costs reflect this process. The experience developed from this project is to be applied to a second phase of development. It is expected that additional environmental cost will be substantially reduced, by perhaps 50%.


Developer's Comments

It was recognised that several sustainability goals are not without conflict or the need for compromise. It may be difficult to reconcile competing goals, for example the need to orientate houses to maximise solar gain may conflict with the need to develop at affordable densities and the constraints of urban sites. It is anticipated that household heating costs will be as little as 1 per week with total energy costs of around 8 per week. The successes learned through this scheme will be further developed in other schemes, and form the basis for future standard house types and procurement methods.

Contact: Stuart Gee,
Riverside Housing Association,
46 Wavertree Road,
Liverpool L7 1PH
Tel: 0151 706 6000
Fax 0151 706 6030
Website: www.riverside.org.uk
Email: stuart_gee@riverside.org.uk