The first development is a millennium community with a standard-setting agenda. The second has experimented with design and won a string of architectural awards. The third has attained top environmental scores in EcoHomes. What lessons can be learned from these innovative homes?
Allerton bywater millennium village
Leeds
Project
Miller Homes is the first housebuilder on site at Allerton Bywater Millennium Village, the second millennium community to be identified by English Partnerships, which will eventually have more than 500 homes plus commercial space. Miller’s scheme comprises 197 homes, ranging from two-bedroom apartments to four-bedroom houses, designed by Philip Rickinson Architects. Miller is working with Leeds council, English Partnerships and CABE on the scheme for the former coal mining village.
Innovation brief
Millennium communities have stringent benchmark standards: to reduce home energy consumption by 20%; reduce mains water consumption in the home by 20%; reduce domestic waste by 50%; reduce home defects on handover by 70%; improve daylight and noise proofing standards by 10%; reduce construction waste by 50%; increase plot and dwelling size; and provide adaptable IT data cabling to each home. Homes also have to gain an EcoHomes top score of “excellent”. The scheme includes home zone areas.
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Whereas the first millennium community at Greenwich, south-east London, has multi-coloured eco-apartment blocks, Miller’s rows of houses at Allerton Bywater look cosily conventional. That is a product of pragmatism, says Steve Birch, Yorkshire regional managing director with the housebuilder: “EP has realised that this is Allerton Bywater and not London, and that some innovation requirements would mean that the build cost exceeds the sales value. It is fine to talk about wind turbines and solar panels, but that may be a step too far for here.”
Still, this scheme has seen the housebuilder working to higher environmental standards than ever before and this is its first project to incorporate a home zone. To meet the environmental standards, the housing has energy-saving appliances and light fittings, water-saving taps and showers, water butts in the garden and recycling waste bins. Miller’s Birch has some concern that although water conservation is regarded as environmental best practice, it is hard to sell to northern homebuyers used to power showers and higher levels of rainfall. The housebuilder could find only one washing machine on the market that would help reduce water consumption by using less than 40 litres of water per wash cycle and that machine was only available in white.
Homes are of traditional construction with full fill blown fibre cavity insulation helping to push wall U-values down to 0.24. Externally, homes have render and western red cedar detailing, with black metal balconies. Roofs are a mix of Delcarmen Spanish Blue slate on homes that face the existing village and Redland red and grey tiles elsewhere.
To score EcoHomes points, timber products used in the homes must come from renewable forests and prove it with a demonstrable “chain of custody” (traceability through manufacturing, transport and distribution). Miller encouraged its existing suppliers to get the required certification. For the windows, however, PVCu was ruled out and Miller was confined to two sustainable supply options for softwood timber windows.
Creating home zone areas proved to be just as challenging as meeting high environmental standards. The idea of home zones is simple enough: instead of housing being developed in conventional car-dominated highways, it is clustered in more pedestrian-friendly streets where there is a single street surface, eliminating the difference between road and pavement, and where trees and front gardens jut into the “roadway”. This is intended to encourage cars to drive at no more than 20 miles per hour. However, because there is no pavement where individual utility connections can be made, before the superstructures were built the scheme’s utility partner, Yorkshire Electricity, “dead jointed” the homes (connected up a phase of homes, then the whole phase to the mains on completion).
Despite standard-issue grey street lighting, the home zones create a street scene that potential buyers like. Visitors to the sales centre also love the showhome’s live/work atelier at the bottom of the garden (a garage with storage space, toilet and upstairs flexible room). Visitors have said they like the extra windows incorporated into the homes to meet the millennium community daylighting benchmark and the back gardens are bigger than they expected to find in new homes.
Innovations worth repeating
The housebuilder is looking at reusing home zones, higher insulation standards and construction waste recycling, and is already using taps with water restrictors.
One point worth making
"There’s a difference in public perceptions on environmental issues in the North, yet environmental standards are being applied equally through the Building Regulations"
Steve Birch
Accordia
Cambridge
Project
The 173-unit first phase of what is planned to be a 373-home scheme on a former DEFRA site in Cambridge has just been completed by housebuilder Countryside Properties. The first phase comprises affordable homes for Wherry Housing Association and private homes ranging from apartments to large houses.
Design of the homes is by Feilden Clegg Bradley, working with Alison Brooks Architects and Maccreanor Lavington. The housing sits in a garden setting designed with mature trees, closed communal gardens, publicly accessible open space and play space by landscape architect Grant and Partners. The first phase of homes has won many design awards, including a Housing Design Award in July.
Innovation brief
Council planners demanded top-quality design for the scheme. Homes are designed to EcoHomes “very good” rating, a standard Countryside commonly applies to its homes. Cambridge council has its own environmental standards – for example, requiring bicycle storage.
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What has made Accordia such a success in design awards is its integration of high-density accommodation into a garden-style environment. The site’s biggest innovation has been the near absence of private front and back gardens to houses. Some houses cover the entire plot, relying on courtyards and terraces in the house and communal gardens to provide outdoor recreational space. That has helped the site achieve high densities of up to 35,000 ft² to the acre.
To arrive at this solution, the housebuilder put in a lot of up-front work. Chris Crook, managing director of Countryside, says: “Some of the initial designs didn’t work internally so we spent three to four months working with the architects on the houses. We built every house type as a cardboard model.”
Design innovation also had to be made to conform to the Building Regulations. Crook says the project’s single biggest challenge was making the four-storey houses designed by Alison Brooks (shown left) comply with regulations, notably for fire safety. For example, a central staircase originally designed to be open plan had to be enclosed by glazed screens.
The team had hoped to use modern methods of construction for the housing. Crook says: “We looked at technologies from across Europe, but we hit on practical difficulties with every one.” For example, the floor-to-ceiling glazing that features in kitchens, living areas and bedrooms was not found to be compatible with modular construction. As a result, the homes are built from concrete, brick and block. Home exteriors echo Cambridge vernacular with their creamy brickwork and solid oak framed balconies.
The green site has been enhanced with swales and apartment blocks have green roofs. The landscaping includes rooftop and garden planters containing herbs and strawberries and residents have continued the theme by planting tomatoes, courgettes and peppers. Homes also score highly environmentally for the generous home offices provided above the garages at the bottom of the garden and passive solar attributes. Bicycle storage is provided in the rear of the garages, which meets the council’s environmental demand but also perversely makes some garages big enough for two small cars. To complete the rural idyll, traffic speed signs and street lighting are attached to the side of buildings so they don’t clutter up the pavements. “That took a bit of negotiation,” acknowledges Crook.
Accordia grew out of a PFI deal by contractor Kajima. Countryside worked closely with its build partner, placing the entire build contract with Kajima and, most unusually in housebuilding, freezing design and specification early. Crook says: “We said that if we fixed the specification on day one we ought to have the buying power to get fantastic quality. It worked tremendously. Bearing in mind the specification for the homes was set three years ago, it still has a wow factor.”
However Kajima departed from the project in January and Countryside is now selling the remainder of the site.
The central location of the site was always going to make it popular with buyers, but the designs have added to its appeal. Smaller houses with minimal or no gardens have been popular. Crook says: “It shows that if you get the way someone can live right, you can overcome issues like traditional conceptions of how a house will look.”
Innovations worth repeating
Much of the learning from Accordia will be going into the housebuilder’s upcoming site at Cliveden Village in Berkshire.
One point worth making
"Have the courage of your convictions when you are innovating in design"
Chris Crook
Broughton square
Milton Keynes
Project
Registered social landlord Places for People has developed 229 homes for private sale, shared ownership, affordable and intermediate rent in one, two and three-bedroom apartments and houses, designed by PRP Architects. Places for People has worked with contractor Willmott Dixon on the scheme, which also includes nine commercial/retail units. Broughton Square is at the heart of the Broughton settlement being masterminded by English Partnerships, which is designed as a sustainable urban extension containing homes for more than 1000 people.
Innovation brief
Like all new housing in Milton Keynes, the scheme has to meet higher than average environmental standards – specifically, it has to attain an “excellent” EcoHomes rating.
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Innovation comes readily both to Places for People and its contractor Willmott Dixon. “It’s part of our strategy. We’ve got loads of these schemes,” says David Cowans, chief executive of Places for People. Willmott Dixon aims for environmental, social and economic best practice on all its schemes – it even has a checklist of “best practice must haves” and “innovation could haves”. The contractor has an in-house EcoHomes assessor, which produced benefits for Broughton Square. Brendan Ritchie, innovation director with Willmott Dixon, says: “We learned that you need to do lots of iterative assessments to reach the standard affordably and practically.”
Places for People project director Nicholas Doyle says everyone benefited from thinking about EcoHomes early: “The team sat down together on day one. We didn’t focus on one environmental area. We went through everything with a fine-tooth comb. We wanted to make this as mainstream as possible. We weren’t looking at a technology-driven solution.”
As a result, there are few clever pieces of environmental technology on site. Homes have waste recycling facilities, energy-efficient boilers, low-energy lighting, water butts and aeration devices on the water tanks to limit use. Places for People did trial Electrisave devices, small gadgets costing about £35, that show people where their electricity is being used (see www.building.co.uk/blogs). Cowans says that although Electrisave doesn’t directly limit energy use, it can have a big impact: “It’s startling for people to see the impact of their decisions. It influences their behaviour, no matter what their income.” Early indications are showing Electrisave is cutting electricity use in homes by 15%.
Willmott Dixon trialled a plasterboard recycling initiative with manufacturer British Gypsum, a process that required the contractor to consult with its supply chain. In the past, the subcontractors had chosen their own plasterboard and didn’t necessarily use the British Gypsum product, so Willmott Dixon had to ensure that buying habits were changed.
The timber frame used to build the homes is inherently environmentally beneficial, explains Willmott Dixon’s Ritchie: “You can achieve a U-value for walls of 0.3 fairly easily. It has good thermal performance.” Sourcing the framing sustainably was not a problem, says Places for People’s Doyle. “There are enough suppliers of timber frame to make it competitive. It is the smaller timber items that we struggle with.”
Doyle set the target of exceeding the 70 points homes need to achieve an EcoHomes “excellent” rating “because we knew that on site there’d be compromises”, he explains. In fact, the homes achieved 74 points both in planning and in reality. Under the EcoHomes scoring system, points that can be earned for site-specific items, such as access to public transport, can be among the most contentious as they may be beyond a developer’s control. Places for People cleverly managed to maximise its scores by tweaking the layout of the site so that none of its homes would be more than 250 m from a bus stop.
Reaching the “excellent” rating raised the build cost by £1887 per unit – quite an achievement when the cost can sometimes reach £3000 per unit. The RSL was able to use profit from its private sale units to help pay for the environmental features. Places for People’s Cowans explains: “Significant help came from EP, but [unlike RSLs doing only rent and shared ownership] we do not lose the profit from the sale of the private homes, so that allows us to cross-subsidise across the scheme.”
Innovations worth repeating
Places for People will install the Electrisave device in more homes if it’s successful and the RSL is using the EcoHomes procedures that worked so well at Broughton Square on a current scheme. Willmott Dixon has extended plasterboard recycling to all sites.
One point worth making
"It is entirely possible to marry consumer preferences for the known with some pretty radical approaches. But you have to look at things on a site-specific basis. There’s no panacea"
David Cowans
Source
RegenerateLive
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