Case Study 2 - Local Sourcing and Partnership
Kingdom Housing Association, Turner Crescent, Methil, Fife
| Type: | New build, timber frame, terrace and semi-detached |
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| Number of units: | 15 | |||
| SAP rating: | 97 | |||
| U-values: | 0.18 Wm2C roof |
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| 0.25 Wm2C walls | ||||
| Fuel costs: | £7.75 pw (predicted) | |||
| Works costs: | £854,137 total |
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| Unit cost: | £56,466 | |||
| Completion date: | August 1999 | |||
| Contacts | Client | Kingdom Housing Association | Bill Banks | 01592 631 661 |
| Architect: | Fife Council | Fraser Middleton | 01592 416 414 | |
| Builder: | Bracken Lea Homes | Tom Daley | 01383 882882 |
The brownfield site selected is close to local amenities and ideal for passive solar gain, facing south with large sheltering walls to the south and west. The layout of the housing has been optimised to take advantage of solar gain by grouping car parking at each overshadowed end of the site (Figure 2.1). This also usefully separates cars from pedestrians. Car parking itself has been reduced below planning guidelines to 1.5 spaces per dwelling. The development takes the form of traditional housing with a mix of 1, 2 and 3 bedrooms.
Figure 2.1 Plan of scheme showing passive solar layout and communal car parking
Key Features
Resource Conservation
Grey water recycled, water conservation, waste minimisation on site
A proprietary system filters waste water from the bath and showers before pumping it into a separate header tank which then feeds the WC cisterns. Spray taps, low capacity WC.s, showers and rainwater butts all reduce water consumption as well. Unusually, the contractor was asked to provide a 3-skip system (timber, plastics, aggregates) which separated out waste from the site. Masonite timber I -beams use 63% less timber than normally required for the main structure.
Social and Management
Environmental audit of contractors, environmental management of Association, partnership
Two features which stand out particularly strongly with this scheme are the rigourous approach taken to selecting contractors on an environmental performance basis, and the actual environmental management of the Association.s day-to-day activities. A traditional competitive tendering procurement route was selected for this project. The contractual audit consisted of a questionnaire which asked short-listed contractors about their environmental policies.
The housing association has a .Green Group. which promotes environmental practice within the organisation. This has resulted in an environmental action plan which has already reduced resource consumption in the office.
The housing association also formed a Partnership Forum which would generate a holistic approach to the design. This benefited the development greatly by providing advice on the environmental specification. The client has benefited from an arrangement with Fife Council which allowed it to obtain a good site at zero cost.
| Partner | Role |
|---|---|
| Kingdom Housing Association | Client |
| Fife Council | Planning, design and donation of site |
| Herning Housing Association, Denmark | Expertise on sustainable design from leading country |
| S.E.P.A. | Expertise on water conservation and waste minimisation |
| East of Scotland Water | Expertise on water conservation |
| Forward Scotland | Expertise on resource conservation and energy strategy |
| Scottish Homes | Main funding body |
The association has instigated a number of social .spin-offs. from the project. It is developing an educational resource pack for the local primary school as well as providing a site for a schools eco-project. The aims and details of the project have been disseminated to all tenants via a dedicated briefing process that will help to integrate the project.s innovatory ideas into mainstream thinking.
Other Relevant Aspects
The Site
Biodiversity, porous paving, swale drainage
Porous paving blocks to the carpark areas allow surface water to drain naturally into the local water table via a drainage swale that feeds into a communal wildlife garden, preventing drainage surge in existing gulleys.
Energy Use
Figure 2.2 House plan layout showing passive solar gain.
High insulation, solar panels, sunspaces, passive ventilation, micro-climate modification
Wall insulation: 170mm Warmcel Cellulose
Roof insulation: 200mm Glass fibre.
Sunspaces: the 1200mm deep sunspaces vent into both the bedroom and living space, maximising the benefit of passive solar heating. Service spaces (kitchen, hall, bathroom, store) are to the cooler north side while living rooms and bedrooms are to the warmer south side.
Solar Panels: heating for hot water is provided by solar panels on the roof which is topped up by a standard gas boiler in each house when necessary (Figure 2.3).
Passive ventilation: a proprietary system allows hot stale air to rise through ducts to the roof ridge vent without fans, reducing energy and maintenance costs.
Micro-climate modification: Heat-loss through the fabric has been minimised by reducing wind velocities around the buildings using a stepped layout to increase drag, as well as the use of planting and external structures.
Figure 2.3 Solar panels and sunspaces combine to save energy
Healthy Dwellings
Local and sustainable materials
- An environmental specification which sourced sustainable materials and products as locally as possible included the following:
- Clay common brickwork from local factory (reducing transportation)
- Filcrete Masonite Engineered Timber Frame (sustainably managed timber and timber waste)
- Warmcel insulation(100% recycled waste paper)
- Water based paints (low toxicity)
- Natural wooden floorboard finish (except kitchen and bathroom)
- Linoleum floor finish from local factory (reducing transport and low toxicity)
- High efficiency combined solar/hot water cylinder from local manufacturer
- Wood framed windows
- Natural clay roof tiles
- Natural clay drainage
Costs and Maintenance
Costs are approximately £10,000 per unit over standard costs. The scheme attracted £48,000 sponsorship in kind to offset the additional costs of the solar panels, grey water system, sunspaces and additional space. There will be some additional maintenance issues associated with the solar panels and greywater system.