|Climate, Environment, Buildings & Energy|
The Stamford Brook PII project is a unique record of the achievements, successes, failures, problems and solutions that can occur during the implementation of an advanced energy standard on a large scale housing development. Using participatory action research methodologies, the research project team has followed the progress of the development from initial discussions on the energy standard and environmental standard, through the detailed design process, observation of construction of the dwellings, performance testing of completed buildings and monitoring of occupied houses. The project has been a collaborative effort between land owner, housing developers, sub-contractors, supply chain, regulatory bodies, householders and the research team. The data obtained during the project and the implications on issues such as building regulation, future energy standards, dwelling design, construction processes, training, quality control procedures and occupant behaviour will inform the UK housing industry as it rises to meet the challenges resulting from climate change and the proposed new energy targets due in 2013 and 2016. It is expected that the results from the project will directly influence the development of new energy standards, building regulation, test methods, dwelling design and construction practice.
Stamford Brook is located on land which once formed part of the National Trust’s Dunham Massey estate. The estate was left to The National Trust in 1976 by Lord Stamford and is now run by the Trust as a ‘Special Trust in Credit’. This means that the estate has to find all the income for its upkeep from its own resources such as from visitor income and rents from its farm tenants. It receives no external funding. When Lord Stamford left Dunham Massey to the Trust, he was concerned that it should continue to be run as a ‘traditional country estate’. With some foresight, Lord Stamford identified certain areas of land on the estate as investment land, which if necessary, could be sold to raise funds for the future upkeep of the Dunham Massey Estate. One of these was the 25 hectare parcel of land at Brookside Farm which now forms the Stamford Brook development.
The National Trust took the decision to maintain a degree of control over the scope of the development and to work in partnership with the two chosen developers. The Trust wanted to ensure that the development was carried out in a way that was environmentally sustainable, was designed to reflect the quality and character of traditional homes in the local area, that would create and attractive urban fringe environment for the benefit of residents, wildlife and the existing local community and that could also serve as an exemplar of a sustainable development. As part of the partnership agreement a comprehensive environmental performance standard (EPS) was developed that set performance targets and requirements for energy use, water conservation, waste minimisation, recycling and material selection for the first phase of the Stamford brook development that were in addition to those required under building regulation. The additional costs to the developers of meeting the EPS criteria were funded by the National Trust from the payments made by the developers to purchase the land at Brookside Farm. The National Trust retains ownership and responsibility for the upkeep of the green spaces in and around the Stamford Brook development and all homeowners pay an annual maintenance charge towards the cost of maintaining the common areas.
The overall PII project objective was to support future reviews of Part L of the Building Regulations by evaluating the various impacts on a large scale masonry housing development of a range of improvement measures that could be used to meet the requirements of an advanced energy performance standard that would likely be introduced as part of such a review. The impacts and issues that the project was designed to assess included the following:
The Centre for the Built Environment at Leeds Metropolitan University worked in partnership with the following organisations during the Stamford Brook project:
The project used an action research approach, in which the research team simultaneously participated in and observed the various aspects of the development process. A combination of qualitative and quantitative tools was used to observe, assess and evaluate the design, construction and occupation phases of the development process.
The Energy Standard being used at Stamford Brook is the Leeds Met EPS08 energy performance standard. The EPS08 standard was originally developed by Leeds Met as a prototype energy standard for the St Nicholas Court project with the intention that it would inform the revision of the Building Regulations that was expected at the time to occur in 2008. The EPS08 standard defines elemental target U-values for the main construction elements, a maximum limit for air permeability and a limit on the carbon intensity of the heating system. In EPS08, calculated U-values include all contributions from both point and linear thermal bridges. A summary of the main requirements of the standard is given in Table 1. Compliance with the ESP08 standard is by one of three routes. This can be either the elemental standard as shown in Table 1, an equivalent mean U-value or by a carbon index calculation. The equivalent carbon emission rate for an EPS08 compliant dwelling would be around 10% to 15% better than that required under Part L1a 2006, depending upon dwelling form and size. For example, an 80 m2 semi-detached dwelling built to EPS08 would have a calculated annual Dwelling Carbon Emission Rate (DER) of 20.6 kgCO2/m2 compared to the ADL1a 2006 Target Emission Rate (TER) for an 80 m2 semi-detached dwelling of 23.2 kgCO2/m2. EPS08 also stipulates minimum performance requirements for ventilation of the dwelling as shown in Table 2.
Table 2 – EPS08 Prototype Ventilation Standard Requirements
Party Wall Thermal Bypass
The Stamford Brook project is funded/resourced by the Department for Communities and Local Government (under Partners In Innovation project - CI 39/3/663), the National Trust (land owners) and the developers (Redrow Homes and Bryant Homes) with contributions from The National House Building Council, the Concrete Block Association, Vent-Axia, and Construction Skills. The contribution from all partners is gratefully acknowledged.
Lessons from Stamford Brook: Understanding the gap between designed and real performance
Stamford Brook Final Report Pre-publication Version
Lowe, R., Wingfield, J., Bell, M. and Bell, J.M. (2007)