Everyone is building sustainable housing now, but can they do it affordably?

A key challenge of the introduction of and any housing standards, both in grant funded housing or in the open market, must be for them to be implemented in a cost effective way in order to ensure their success in volume.

Any process of introducing change (like the Code for Sustainable Homes, for example) needs to incorporate a means of managing cost to a realistic level.

Here’s what it cost to build the Lingwood scheme:

The construction cost of the fifteen GreenGauge Homes at Lingwood was £1.618m excluding fees and VAT. This was the amount tendered by the winning contractor, Youngs Homes, in Q42006 and includes all renewable technologies and Rain Water Harvesting.

Of the £1.618m construction cost, £540,000 was a Housing Corporation Grant, £147,000 a grant from Broadland District Council and a further £16,216.91 was provided by the Low Carbon Buildings Programme.

In addition, Carbon Connections funded the Monitoring programme to the tune of £56,000.

Comparison with a similar scheme of the period

Lets compare the Build Cost of Lingwood against a Conventional Ecohomes Very Good scheme of the same period. “Very Good” was the requirement for grant funding of affordable housing assessed in 2006, so it constitutes the required level at the time.

The scheme of 15 homes at Lingwood cost £108k a unit (Total Scheme Cost including fees, post planning). A scheme of the same period in the village of Bawdeswell, of 8 houses and with no renewables (which received Ecohomes Very Good) had a Total Scheme Cost of approximately £850k equating to £106k a unit. Both schemes were built by the same contractor.

In actual cost terms for the client the difference in the cost to build Lingwood was just £2,000 a unit.

So how can this be possible – surely the renewable technologies cost more than this? Well yes, they did, but it was possible to manage the cost of introducing them. Here are five ways to avoid your project cost spiraling out of control

1. Don’t invent anything

As soon as you start inventing new components, whatever they are, you have to incorporate the costs of the development, and of bespoke components, into your build. Why bother? The climate change agenda was already far enough advanced in 2006/7 for us to choose with relative success a range of tried an tested technologies. The more tested the technology is, the less likely it is to go wrong or involve you in additional expenditure to make it work.

The homes at Lingwood are built using a standard Space4 timber frame, with additional insulation applied. We could have developed a new construction system, but several were already on the market with a good reputation and perfectly adequate for our needs.

2. Don’t Change things that don’t Need Changing

Just because you’re doing something new you don’t have to do everything new. Our affordable housing is developed along a standard housetype which, like the technologies we used, was tried and tested, built on years of experience designing for RSLs. A standard housetype reduces the cost of frame production, and yes, offsite manufacture keeps preliminary costs down too.

The layout for Lingwood is also very simple and straightforward. Broadland District Council’s planning officer initially thought it was too urban an arrangement, but was supportive when it was explained how all the houses needed to be South-facing. As it turns out the site has a very strong sense of community, and a balance of outward and inward facing houses has helped encourage this.

Even the windows at Lingwood are simple Jeldwen windows. They serve the purpose required by this project.

3. Avoid indulging in fripperies

Building sustainable housing can easily become an exercise in outdoing one’s competitors. The temptation is to make the housing look different, introduce unique components, make the building particularly photogenic to win competitions. So easily a small exercise can become someone’s pet project.

But pet projects cost money, and whilst there may be benefit in PR, is this the intention? If you have a longer term objective, think to the longer term.

4. Consider Everything Carefully

Thinking of using a particular element in your scheme? Ask yourself, Do you need it? What for? If you do, how can you make the best use of it?

At Lingwood there was an opportunity to generate wind energy, and micro generation was very popular in 2006/7. But how would we do this? A single turbine is more efficient than four singles, but it would be difficult to share energy (without storage) between four individual households. We were also convinced that PVs would generate more energy for the householders for the same capital cost. Lower running costs were an important objective of the project. When a study demonstrated that the site was not suitable for wind energy generation, it was a simple step to choose PVs instead.

5. Remember your Objectives

Affordable housing needs to be affordable. The client RSL wants to be able to manage the housing easily. The contractor wants to be able to build it simply and cost effectively, and we all want to repeat a successful project with another.

Keeping sight of these objectives helps us make the decisions which lead to a successful outcome. Its not rocket science.

Broadland District Council has awarded the GreenGauge Homes at Lingwood a High Commendation in their bi-annual design awards. The awards enable the Council to “encourage and recognise the special efforts which have taken place to raise the standard of design in the Broadland district”.

This is the third award which the scheme of affordable housing in Norfolk has received, the others are the CPRE Norfolk Award and the LABC East Building Excellence Award.

The project was nominated by a Planning Manager within the council and the judging panel wrote:

“This is a pioneering development of 15 affordable homes of simple, unfussy form and mixing traditional and modern materials. It is also a working experiment in sustainable and economic design and construction, using different combinations of technology in each of the four blocks, including solar collectors (both for heating and electricity), heat recovery, ground source heat pumps and very high levels of insulation. One block has efficient gas central heating to act as a comparison with the remainder. The aim is to find a readily-reproducible, cost-effective and highly energy-efficient solution for future housing development. The project is being monitored by the University of East Anglia.”

The affordable homes are also amongst six finalists for the National LABC Building Excellence Awards which are to be presented in a ceremony in London in October.

The houses at Lingwood are a mixture of 2-bed 3 person and 3-bed 5 person homes, designed to meet the developing association’s Design Brief. All homes were south facing, arranged in a pair and three terraces. All the houses are timber framed with untreated larch cladding and high levels of insulation. In many ways they were very conventional affordable homes for their period.

What makes the GreenGauge Homes at Lingwood different is not the layout or aesthetic, but the use of the project to evaluate a range of tried and tested energy saving and generation technologies already on the market, with conventional tenants in permanent residence. The data collected would inform future developments and avoid costly mistakes.

The houses are arranged in four groups.

• One pair of homes is heated with highly efficient gas condensing boilers. These would act as the ‘control’ group against which to compare the others.

• A Solar group use solar power for a substantial proportion of energy requirements. Solar collectors pre-heat the water fed to the gas condensing boiler for hot water and central heating. In addition, Solar PhotoVoltaics on each home supplement conventional electricity supply for lighting and power.

• A Sunspace group incorporate a double height conservatory to the south facing elevation of each house. A black facing brick Trombe wall is used to store heat during the day and release into the sunspace during cooler hours. A mechanical ventilation and heat recovery unit heats and ventilates all rooms using energy from the sunspace. Backup heating is by gas condensing boiler with radiators.

• The Ground Source Heat Pump Group of homes is the only group without a gas supply. All space heating and hot water is provided by a vertical array of ten collector pipes and a 5kW Heat Pump in each house. Space heating is via underfloor heating on the ground floors and radiators upstairs.

Why were these combinations chosen?

As with all design projects, there are a number of factors.The houses are a standard size and layout in accordance with the housing association’s brief, and this influences what size of sunspace is possible, for example.

Why didn’t we use wind turbines? At the time of construction, rooftop wind turbines were very popular, but the site was evaluated as not suitable for turbines so they were ruled out. In the event this has proved fortuitous as the effectiveness of micro-wind generation has since been called into question by others.

Many rural affordable housing sites do not have a gas supply, so a solution which doesn’t need gas can save the cost of a connection, and as the price of gas increases, that solution will be more attractive in the long term too.

The project was completed in February 2008 and monitoring began.

Building affordable housing on rural exception sites is a difficult business, involving a wide range of stakeholders, and the funding structure is strict. If an RSL is to invest in raising the sustainability standards of its properties across the board, it has to do this from the basis of reliable information – it can’t afford for projects to go wrong.

It was in this climate that the Lingwood GreenGauge Homes project was born, in 2005, when achieving the EcoHomes ‘Very Good’ rating was the standard, and two years before Level 3 of the Code for Sustainable Homes would be the minimum required level for all Grant Funded housing in England and Wales.

The Brief for Lingwood was to be:

• 15 houses for rent and shared ownership on a conventional exception site, suitable for a conventional mix of tenants.
• Built to EcoHomes Excellent rating, in advance of its peers.
• Trialling a range of technologies for reducing the carbon load of the construction and energy in use
• Cheaper to run, reduce running costs for tenants and promoting sustainable energy use
• Monitored both socially and environmentally to inform future projects.
• Able to be built within the standard funding structure.

It was hoped that the collection of real data from real tenants in replicable houses would provide the information that product manufacturers could not – information about how the technologies would work on the ground. This project was not an ‘experimental scheme’ and uses readily available products to produce exemplar affordable houses.

Coming Next – About the Houses

Welcome to the GreenGauge Homes website.

This site is being developed to share information about the GreenGauge Homes approach to developing sustainable affordable housing.

Over the coming months we will be publishing a range of material on this site including:

• Information about the GreenGauge Homes approach to sustainable housing, for example “Why are GreenGauge Homes not Kit Houses?”;
• Details of the first GreenGauge Homes project at Lingwood in Norfolk;
• Findings from the social and environmental monitoring of the Lingwood Project, which was carried out by the University of East Anglia’s CSERGE unit;
• Information about the next GreenGauge Homes project which will soon start on site

Please subscribe to our RSS feed , follow us on Twitter or sign up to our email newsletter to be alerted when new data is published here.

And in the meantime, why not read about the participants in GreenGauge Homes projects thus far, check out our news archive and find out how GreenGauge Homes can help your sustainable housing development strategy.

When the Ecohomes standard was introduced, followed by the Code for Sustainable Homes which replaced it, these standards were first compulsory for Grant Funded Affordable Housing, that is, most housing developed by housing associations.

As a result the first to respond in a significant way to the demands of these codes were the developing housing associations.

Some associations built special ‘one off’ projects, for real tenants, in an attempt to demonstrate that sustainable living was possible. It was common for these schemes to be designed to environmental standards far beyond the requirements of the time, and to be seen as opportunities to make large strides into unknown territory. As a result the schemes often included unusual houseplans, experimental materials and technologies that would require significant changes in lifestyle for residents.

As the demands of sustainability legislation began to affect the construction industry as a whole, organisations like the Building Research Establishment [BRE] set up “Exemplar” houses which were not for occupation, but experiments to test new construction technologies, techniques and materials – such as the houses at the BRE Innovation Park. These houses are routinely funded by construction companies and product manufacturers, and designed by competition, with the concomitant media enthusiasm.

If you are a housing association developing affordable housing for rent or shared ownership, or a developer working for the open market, these types of approach, whilst interesting, do have their disadvantages.

1. You may find yourself with properties which are so unlike ordinary houses that residents need a complete lifestyle change to benefit from the technologies. The designs, different from the familiar, may not be popular, may be costly to build and maintain, and ultimately are unlikely to be built in any volume;
2. The innovative, experimental nature of ‘exemplar’ homes and the fact that they are developed through sponsorship can create a cost environment which, whilst generating some data and much interest in the press, is difficult to reproduce in volume without further additional steps in development, on a more competitive cost base, and with residents.

But in the meantime we have been working on a different, bottom-up approach.

Five years ago Barefoot and Gilles proposed to our long term clients Flagship Housing Group and their agents, Oxbury & Co, that we should start with the homes, methods and people as they are and work from there, instead of trying to get the highest eco-credentials and failing to meet any other criteria, in particular, capital and operating cost.

GreenGauge Homes are real houses with real tenants. Each scheme is designed for a particular site as normal. The client decides what particular approach they want to trial in the scheme (e.g. they want to be EcoHomes Excellent and trial various renewables technologies, as in the first project at Lingwood, or perhaps they want to be better than CSH Level 4 and with potential to easily meet Level 5, as the second scheme at Horstead) the effects are monitored and the result is a working group of houses and with a wealth of data to inform the briefing process for the next generation of the client’s housing.

GreenGauge Homes are:

Sustainable - one step ahead of the current required standards, i.e. what the developer will be building in 2 years time. Not the ‘best’ but ‘more than good enough for now’. Through small steps we aim to reach further in a meaningful, affordable way.

Flexible - not a kit house, but each designed for the site and the time. Using tried and tested techologies rather than risky new-to-market products which don’t have a history or reliable future. Maintenance is a big issue for Housing Associations.  It is worth noting that this approach means GreenGauge Homes can look different and be built using different materials. What is important is that they are appropriate.

Affordable - Able to be built within the standard grant funding structure. Additional technologies are funded by grants wherever possible, but we aim to keep additional costs low – as little as 3-5% above a standard home of the time.  The client can use their preferred contracting team who are not fed big surprises (or additional risk). Also, if you would like tenants to benefit from reduced energy bills, and learn more about sustainability, these can be additional objectives.

Measurable - each project is monitored after the tenants/owners move in so as to learn the most about the energy use and residents experience. The first houses at Lingwood have now been monitored (under occupation) for a year and there are a wide range of findings we hope to publish in the coming months. In particular we have learned a great deal about how people react to the homes, as well as if they save energy!

We intend each scheme of GreenGauge Homes to improve on the previous ones, creating a body of knowledge and expertise for future projects and generating decisions about strategy so that the RSL’s we work with can update their Design Brief for all their housing safe in the knowledge the changes have been tested.