Transition Town Letchworth (TTL) have welcomed the opportunity to view the entries to your design competition. We were pleased to see a range of ideas across the entries for tackling the problem of moving to a more sustainable way of living. TTL still have concerns about the site chosen for this development, in particular the difficulties this creates for a successful shift to sustainable transport when the site is a significant distance from key services and the train station.
With four high quality entries, and so much information in the design sheets and supporting documents, comparing the entries was a challenge! To help us undertake this task TTL analysed each of the entries according to features we had previously identified as important in our report, ‘Sustainable New Neighbourhoods for Letchworth Garden City’. This analysis, which can be seen in the table at the end of this document, helped us identify the strengths and possible weaknesses (as suggested by a lack of information) in the presented designs.
Identified weaknesses in an entry could still be addressed at this design stage, some weaknesses may even be addressed after the estate is built. However, it will be prohibitively expensive to address weaknesses in either the build energy efficiency of homes or provision of renewable energy once building work had commenced, so this must be got right at the design stage.
We understand that the government’s intention is that gas will not be provided to any new estates after 2025. TTL’s expectation is that the Heritage Foundation would have made clear to competition entrants that there will be no mains gas supplied to the new estate and the estate should have a net self-sufficiency in energy. These requirements should have forced the designers towards zero carbon build solutions.
Building zero-carbon homes is essential both for tackling climate change and for ensuring ‘affordable’ living costs. Options A and D both recognise the need to achieve the level of performance of ‘passive houses’ (zero carbon), it is less clear on the aspirations for build energy efficiency for Options B and C. Option A and D recognise that builders do not always deliver the quality of homes that architects plan and have addressed this with the onsite factory house building approach. The renewable energy requirements for passive houses should be very low and some modelling needs to be done to ensure that sufficient renewable energy is included in the chosen design whilst not driving up estate costs by over-engineering the renewable energy solution. Option A implies that coppicing biofuel, geothermal and Solar PV would be necessary but Option D suggests energy needs can be met using Solar PV and a community grid. (If the new estate is over-engineered this could help the existing town reduce its reliance on fossil fuels through the provision of coppiced biofuel and a district geothermal heating system, which would be a beneficial, but the design should identify the planned beneficiaries from each element of renewable energy infrastructure.)
The competition was to design a suburb to a town, so we believe it should be designed in a way that encourages its residents to integrate with the population of the existing town. The only proposal that seems to consider the effect of this estate on existing residents is proposal D. NHDC local plan does not help with this issue by asking for a new primary school on the site. We would suggest that existing primary schools could be extended to ensure better integration of the new residents into the wider town. Locating a medical centre on the Grange, where there is already a pharmacy, would provide benefits to both Grange residents and the new estate residents. Valuable farmland is being lost to provide space for schools and doctors surgeries that could be provided for on the existing Grange estate. A nursery / pre-school with after school care may be a more appropriate service to have on the new estate ensuring childcare is within walking distance.
None of the proposals have identified the importance of permaculture as a growing technique (agroforestry is the closest we get to this in Option B). Permaculture can produce higher yield and take less maintenance than more conventional growing techniques and the new garden city suburb would be an amazing showcase if its food growing was based on permaculture food production techniques.
We are pleased to see the entries include solutions for tackling water shortages in the area. Some modelling would be helpful to see if local rainfall levels could support the water features being proposed, as empty ditches will not be as attractive as the water features in the pictures.
The level of detail of the designs makes it difficult to check that there are safe, direct routes to walk and cycle to the secondary schools, station and town centre but we hope that these will exist.
Existing estates in Letchworth would benefit from retrofitting some of the features suggested in the competition entries and we would like to encourage the Heritage Foundation to consider how ideas can be transferred to benefit the wider town. For example:
- Could any excess heat or electric energy be supplied to residents on the Grange Estate and would this help reduce their fuel costs whilst lowering the carbon footprint for the town?
- There is lots of potential growing space in other areas of the town, wide grass verges and big open green spaces which could become community growing spaces.
- There are plenty of opportunities for improving the cycle and walking infrastructure as well as reducing the attractiveness of cars journeys and ownership of cars.
An Analysis of Letchworth Heritage Foundation Garden City Extension Competition Finalists By TTL Identified Important Issues
|Entry||A. Growing Letchworth||B. Growing Together||C. Gardenia||D. Grange-In-The-Hedges|
|Housing Numbers||900 dwellings||910 dwelling
1710 parking spaces.
|973 – Significantly more than required from the site!||900 dwellings|
|Energy Efficiency of Housing||Recognition of what is needed to get houses built to passive house standards with the local factory build approach applied to ensure standards are met.||District heating but not clear what energy source is.||Recognition of what is needed to get houses built to passive house standards with the local factory build approach applied to ensure standards are met.|
|Social Integration||Words imply need for social integration is understood but diagrams show clustering by housing types which is concerning. Bigger houses are also those with the views out into the countryside.||Suggests a good mix of tenure and typologies in each hamlet.||The perimeter blocks are surrounded by a mix of dwelling types and tenancies and there will be a tenancy blind dwellings.|
|Integration with Existing Town||Buffer to existing homes.||Buffer to existing homes.||Recognises that this site is to the detriment of the Grange which it tries to address through Green Wedge idea etc.|
|Local Food Production||Small productive community gardens provide spaces to grow food and the linear parks will also be used to grow food. Fruit trees also on the local lanes.
Mentions orchards but not clear if there are big areas of orchard or these are just down avenue.
Has different fruit on different lanes, is this good or would mix be better to give seasonal fruit to local residents.
We like the idea of shared garden spaces for co-operative housing blocks and older peoples units.
|Recognises the Incredible Edible idea.
Has communal food growing land in each hamlet.
Agroforestry idea so trees mixed with animals and crops.
|Has a vast amount of food growing ideas, huge number of greenhouses as well as conservatories. Would allthese be used?
City Farm seems a strange idea given that Standalone Farm is adjacent to the west end of the site.
It’s surprising to us that it has fences and not hedges between houses.
|Residents have land in the perimeter blocs that they can decide how to utilise, community led is really important in successful community gardens.|
|Transport||Roads with pedestrian and cycling priority / routes. Neighbourhood parking with access to houses for deliveries.
PV on car parking hubs so subsidised electric car parking.
|Transport hub and communal car parking in hamlet.
Access from south restricted to those using public transport, sustainable transport or car sharing. Will this be acceptable or workable?
|Transport hub and energy centre. Supports electric vehicle charging.
Electric bus charging
|Community car club.
Ride sharing App.
Minimise roads in estate to discourage cars but have better connections for cycle and pedestrian routes.
Recognises the importance of visually attractive routes to encourage walking and cycling.
On street parking will be on re-enforced grass.
Solar powered motion sensing street lighting.
|Housing Tenures||None of the submissions address this important factor: the proportion by tenure for each type of dwelling.|
|Flexible Housing||Residents can configure the internals of their homes.||Typologies have options for changing and growing over time.||Garden rooms are promoted as an approach to an adaptable housing unit.||Adaptable home idea for multi-generational family recognised.
Older persons houses recognised as part of mixed tenancy areas.
|Community Building||Pocket parks and communal gardens.||Suggested a sharing App for food and cars.||Sharing app for transport.||Sharing App which covers cars, space sharing, care activities, business and economic relationships.|
|Water||SUDs, Swales and water for cultivation.||SUDs, Swales and water for cultivation.||Going to have a natural swimming pond!
Each cluster collects its own rainwater in a tank above ground.
|SUDs, Swales and water for cultivation.
Greywater systems in housing.
Wetlands for cleaning water.
|Renewable Energy||Ground source heat pumps.
Managed coppice for biomass.
Mentions a community scale energy system but not clear if this will provide electricity and heat,
|Passive heating through winter gardens.
Provision for fuel cell technologies and ground source heat to provide decentralised heat and power.
|Solar roofs and an energy network.||Solar PV on roof panels and a community grid for sharing.
Would it be cost effective to have solar panels on ground before installing them on roofs or better just to have tiled solar roofs this avoiding the cost of roofs and panels?
|Mixed Use||Business Premises.||Commercial spaces in apartment blocks.||Business premises.|
|Waste Management||Communal composting.||Communal composting.||Communal composting.||Communal composting.|
|Greenway Development||Enhancing greenway with wildflower walk.|
|Community Venues||Central Area proposed. Factory repurposed as part of this.||Central Area proposed.||Central Area proposed.||Central Area proposed.
Factory repurposed as part of this.