This new Poundbury-influenced housing by Cornhill Estates and Miller Homes deserves attention for breaking with tradition with some modern eco-specification photovoltaic solar-energy roofing, according to Lafarge Roofing.
No wonder this 204-home stage of 40ha greenfield development called Parkside in Upton appears so royally connected to Poundbury, because it is actually part of a 1,000-home masterplan by the Prince's Foundation, EDAW and Northampton Borough Council as a commission for landowners English Partnerships. Cornhill was also the developer of the housing at Poundbury.
Whilst traditional in design and layout based on outline-planning approval obtained in 1997, the townhouses and apartments for this conservative-looking "Poundbury II" plot B within the second of eight phases had to meet the very latest stringent environmental requirements.
So when the design is described as "excellent" it is actually the official language for the BREEAM Eco Homes Energy Rating of 10 that the homes achieve.
This rating is the very maximum possible and explains why 25 of the traditional designs for plot B have still succeeded in incorporating modern photovoltaic (PV) solar roofing technology.
This is the remarkable technology that converts natural solar energy from sunlight into household electricity.
At face value before installation, this technology manifests with all the shininess of industrial glass cladding, but when fitted such as on plot B, it blends amazingly well within the tradition of roof slating.
The PV system is manufactured within the famous Redland range by Lafarge, as also used to up the sustainability of many schools and housing throughout Britain with a little help from Energy Saving Trust grants.
Each of the 25 solar roof's 960kWh annual output should generate around a third of a typical family's electricity demand in the Parkside development, to save some 400kg of carbon dioxide emissions as well as reduce fuel bills.
Assembled in the UK, the universally-fitting Redland PV panels measure 1200mm wide by 520mm deep to integrate directly with slates, tiles or even metal sheets on pitches between 25 and 60 degrees.
Contractor Broadbents installed 16 of the PV panels to take up some 10m2 of each roof clad for the Parkside development with traditional natural slates.
Just as the panels overlap like the surrounding slates, their weight is comparable so there's no need for strengthening to the load bearing members. Connected by slotted metal channels located at the top and bottom of each panel, the units are screw-fixed back to standard 50x25mm tiling battens that match those used for the slates.
Flush-fixed metal flashing elements finished in discreet black provide neat weathertight junctions between the PV panels and slates at top, side and eave sections.
The panels are connected in series by ready-fitted plugs and sockets. These are designed for best handling safety, being impossible to connect the wrong way round.
Each PV panel array is connected to an electrical inverter, that converts the variable direct current (DC) electricity into useable mains voltage alternating current (AC).
The inverter is connected to a standard domestic consumer unit fuse box, which transmits out as usual through all the wiring. These houses have even been connected to feed any surplus back for sale into the National Grid.
But it's not just solar power that is harvested from the roofs. All the homes are finished with rainwater harvesting butts, which is the simple but ingenious way for occupants to collect all the water that drains from a roof slope.
It's not uncommon for just one storm to completely fill a 205-litre tub, to reduce water rates and overcome any summer-drought hosepipe bans.
As well as southerly-aspect houses also having solar water heating systems on their roofs, it is known that 25 homes for more modern designed phases will have green roofs, which is the ingenious way of using special planting as the outer roofing layer to compensate for the building's carbon footprint.
"I've seen whole modern suburbs built with eco-spec PV housing in the Netherlands, but it's still impressive to see the diverse environmental roofing measures applied to this traditional British housing," said Lafarge Roofing spokesman Stuart Pocock. "I hope at last it will help kick-start a genuine move for British housing to be much more environmentally friendly - especially if the roofing industry can play such a vital role."
Miller Homes was given the go-ahead in the spring for the next modern designs to be developed at Parkside. The overall development is so big and diverse in style, that it's even involved a New York-based architecture practice Cusato Associates. So expect even more interesting roofing to come.