Wherry Housing Association (Circle Anglia)

Vote now!

PROJECT NAME: Greening the Box
PROJECT START DATE: February 2009
PROJECT COMPLETION DATE: Refurbishment complete June 2009. Three-year monitoring process: 2010 - 2012

PROJECT DESCRIPTION:

More than a quarter of the UK’s carbon emissions come from housing, and to meet Government targets to reduce emissions housing associations need to embark on a large-scale modification of its stock. Wherry Housing Association (part of Circle Anglia, one of the UK’s leading providers of affordable housing) decided to explore what was possible and launched retrofit experiment ‘Greening the Box’.

Greening-the-Box (GTB) is a pilot being delivered by Wherry in partnership with Broadland District Council and SEArch (Sustainable Ecological Architecture Limited). A 1930s ‘hard to treat, hard to heat’ property off the mains gas network in rural Norfolk was chosen for refurbishment, with the aim of reducing carbon emissions and energy costs for occupants and transforming the building’s standards to those fit for a low carbon future. With no insulation and an inefficient heating system, the property performed very poorly in terms of energy efficiency and environmental impact.

The property underwent 16 weeks of adaptation works before the new residents moved in at end of June 2009.  The residents of GTB, a family of four, previously lived in an identical property next door, where they could only afford to use the electric storage heaters between November and January, which resulted in damp and mould growth. This is an exciting, innovative and unique project that Wherry hopes will enhance the Life Chances of residents by making them less reliant on fuel and minimising the threat of fuel poverty.

Many ‘eco-retrofit’ approaches use expensive, high tech solutions like ground-source heat pumps, which are costly to fit and maintain. In contrast, GTB is a low-tech, practical approach for turning old houses into eco-homes. GTB took a ‘whole house’ approach to refurbishment – looking at every element of the building and how it interacts with its environment and occupants, then taking advantage of anything that might help improve performance.

The GTB home has ‘Zero Heating’ – a natural heating regime that relies on solar heating and human occupation, with supplementary back-up heating. All the windows have been double-glazed, and those on the north have been made smaller, reducing the building’s rate of heat-loss. On the south side, more and bigger windows have been added to maximise the amount of natural light and transform GTB into a passively, naturally heated building. The only other kind of heating in the home is a low-grade electric under-floor heating system operated by a switch – there is no gas fire, no oil or mechanical boiler, no radiators, no flues and no pipes. Super insulation will help the building retain heat - the house’s solid 9 inch external walls have been insulated with an extra 100mm of extruded polystyrene insulation. The heat contribution generated by the occupants and appliances, and a ground floor of dense concrete and the superstructure of the building acts like a storage radiator, holding on to its summer heat for the winter.

Other features include passive stack and cross ventilation to cool the building, 600mm of quilted recycled plastic insulation in the roof, a rotating cowl on the roof to draw air through the house, and breathable walls to reduce condensation. To reduce the building’s environmental impact even further, we added a 1,100 litre rainwater tank, which can be used instead of drinking water for outside activities like watering the garden and washing the car.

The refurbishment has resulted in a home with better energy performance than a typical new dwelling built to the current Building Regulations. GTB clearly demonstrates that the UK’s ‘hard to treat, hard to heat’ properties can be transformed cheaply to become ‘eco-homes’. All that’s needed is a ‘whole house’ approach that uses simple, low-maintenance technologies to keep capital and running costs low.

Looking at the energy footprint of a house over its complete 100-year lifecycle – it is clear that the UK does not need a huge demolition / rebuild programme to bring its housing stock up to near-zero carbon standards. If the ‘embodied energy’ in building a house is taken into account, the GTB refurbishment is more energy efficient in all aspects. With so much to play for – and carbon targets looming the time to act is now.

It’s too early to give a full year’s actually performance results from the refurbishment. However, the building has been assessed using the SAP (Standard Assessment Procedure) methodology.

COST EFFICIENCY:

The total cost of adapting the home is approximately £104,000; however, the bulk of this cost is for non-energy related works made to improve the initial condition of the property – for example installing a new kitchen and a bathroom. The cost of the energy related works is less than half the total cost  £48,000 - a much cheaper and less environmentally damaging approach than demolishing old stock and building a new home.

A three-year monitoring programme will cover Life Cycle Analysis (LCA), Thermal Performance, Energy Consumption and comparative studies against a conventional house. From the LCA calculations, Lifetime Embodied Energy comparisons with conventional housing can be made. It is anticipated that these assessments will demonstrate that the GTB approach to housing adaptation will cost housing associations considerably less over the lifetime of the building.

Managing 1.7 million homes nationally, housing associations face a huge challenge to improve homes, particularly as many residents are classified as living in fuel poverty. GTB demonstrates that retrofitting is a cheaper and more environmentally friendly way of meeting Government emissions targets.

HOW DOES THIS PROJECT DEMONSTRATE CO2 REDUCTION?

More than a quarter of the UK’s carbon dioxide emissions come from housing and existing stock will still  be housing the majority of the UK’s population (80%) in 40 years time. Therefore existing stock must be adapted to meet Government CO2 emissions. GTB is a low-tech approach to building adaptation, which aims to reduce energy and carbon emissions.

The SAP results give a comparable idea of how the refurbished building will perform and indicate an 80% reduction in energy consumption and a 93% reduction in CO2 emissions. And a study using Energy Saving Trust data set the refurbished property alongside a typical modern three-bed room house built to minimum building regulations. SAP scores calculated by the South Holland District Council Building Control department predicted GTB will consume 16% less energy over a year compared to the new build house –to produce 69% less Co2.

Most strikingly, a property once rated 30F for both energy efficiency and carbon emissions now performs better than a new build house built to current Building Regulations, challenging conventional wisdom that new build is always best when it comes to energy efficiency.

HOW COULD THIS PROJECT BE REPLICATED BY OTHER LANDLORDS?

The challenge now is how to replicate the GTB nationwide. Something with a similar impact needs to be happening on a large scale and fast, if the UK is to meet its obligations for reducing carbon emissions.  With around 4 million homes in the social rented sector, social housing has a major role to play in both meeting the target and leading the way.

Wherry is a member of the Retrofit Pioneers Group of the Existing Homes Alliance, and will be disseminating the learnings from GTB through the Retrofit Pioneers Network. Mark Jones, Managing Director of Wherry, will be presenting the current findings at the National Housing Federation’s ‘Keeping in the Roof’ conference on 22 March in London. Wherry also has project website for GTB (http://www.greeningthebox.co.uk).

Following a comprehensive assessment of the retrofit, Wherry will continue to share information with the sector and develop recommendations for replications if it proves to be a long-term, financially viable option. It’s hoped that GTB model will be taken on by more housing associations and local authorities, and eventually rolled out nationally.

However, while this approach is relatively cheap, it still needs investment. Neither social landlords nor tenants have access to upfront finance needed to get refurbishments off the ground on a large scale. The answer could lie in ‘Pay as you Save’ (PAYS) schemes, where landlords use third-party finance to cover the upfront costs of refurbishment, which is then repaid over a long period of time – up to 25 years.

HOW HAVE RESIDENTS BEEN INVOLVED?

The tenants are a family of four who previously lived next door and are an integral part of this project - their input is vital to measuring the success of GTB. They’ll take part in a three-year monitoring programme beginning in summer 2010 - covering life-cycle analysis, thermal performance and energy consumption studies.

The most important shift that needs to happen for GTB to be successful is how the residents see their new home – they need to understand how the building works, and the principles behind it. Learning how to get the best out of their new home will be a challenge and require a different way of thinking – it will  involve  them taking charge of a new, greener environment, rather than relying on technology to heat their home.

The occupants of GTB are still adjusting to a house that works very differently to their previous home – finding the right levels for the under floor heating in winter and learning the best ways to adjust the ‘passive stack’ ventilation. However, they report the house provides a much more comfortable environment, and even credit it with reducing the effects of seasonal affective disorder on one particular individual. The occupants are so pleased with the improved comfort and reduced bills, they have said they would be prepared to pay more rent, even if the increase exceeded the electricity saving. They are prepared to pay more in order to achieve a reduction overall, supporting the idea of the ‘Pay as you Save’ scheme.

Vote now!