Exeter City Council: Passivhaus in Exeter

Exeter City Council have been constructing buildings to Passivhaus standards since 2009, using their triple bottom line approach to deliver high quality builds, by being socially, environmentally and financially responsible. Since starting to deliver Passivhaus homes, they have developed and built nearly 150 homes to these standards. The process of designing and building so many different types of structure, has enabled them to improve their delivery model and in doing so reduce the overall cost.

The challenge

Most of the emissions (68 per cent) in Devon (including Torbay and Plymouth) come from buildings (homes and workplaces) and on-road transport. This is reflected in 74 per cent of all emissions in the city coming from the oil and gas that powers the economy, fuels cars and heats homes. This means that if Exeter City Council is to achieve its net zero target of 2030, there is a need for focused provision that reduces energy usage.

The average UK home emits about 4.5 tonnes of CO₂ per year, with 56,000 homes in Exeter this comes to around 252,000 tonnes of carbon per year. Making our homes responsible for about a quarter of the cities carbon emissions. This is compounded by the current challenge created by the increases in energy costs, which will impact upon everyone across the country. Currently even with government support the typical medium user family can expect their annual energy bill to cost £2,500, plus VAT.

We are faced with the twin challenge of high levels of carbon emissions and the energy costs that come with such levels of energy usage. This makes delivering houses that are more energy efficient crucial. Especially if Exeter City Council is to meet their 2030 net zero targets, while shielding the community from potential fuel poverty both now and into the future.

The solution

Exeter was among the first local authorities in the country to build new council houses to Passivhaus standard. Creating new homes that dramatically reduced the carbon emissions created by the resident and reducing their energy costs.

To tackle the finances required to deliver houses to passivhaus standards, the Council created their wholly owned development company Exeter City Living. Who as well as building council homes, also build Passivhaus homes for market sale The Company have ambitions deliver a further 1,000 homes over the next five years.

In terms of Exeter City Living's approach to developing and delivering Passivhaus homes, they adopt triple bottom line approach, which requires all projects to be socially, environmentally and financially responsible. This approach ensures that the homes created are climate-ready until at least 2080, supporting the transition needed to look after the planet now and in the future, they are also very low energy so eradicate the risk of fuel poverty all while being delivered at a price point that makes them affordable.

The socially responsible element of their approach is based on using Building-biology, to consider how the built environment will affect human health. This approach focuses on building homes that are human centred, healthy, and comfortable.

Exeter City Living aim to meet their environmental responsibility to the planet, by using building techniques and materials that emit lower levels of carbon than traditional building methods, while also utilising materials with a lower carbon footprint.

It is crucial that all Passivhaus buildings built by Exeter City Living offer value for money. This is measured not just by examining the capital cost of the new build but by all assessing the life cycle costs benefits of investing in the fabric-first approach of Passivhaus.Wherever possible local companies and labour are employed to construct the new homes and the cost savings from the energy efficiency of the homes means that residents often spend more in the local economy.

The impact

Over the last 12 years Exeter has delivered construction projects that are national if not international leading. Examples include Edwards Court, the UK’s first Passivhaus extra care Village and St Sidwell’s Point, which is the UK’s first leisure centre to be built to Passivhaus standards. Comprising four pools, 150 station gym, exercise studios, spa, soft play areas and café. Sidwell’s Point will save at least 70 per cent of the energy compared to one complying with current Building Regulations. The leisure centre has already received several national awards and accolades for its pioneering uniqueness.

Due to Exeter’s long-term commitment to Passivhaus they have developed unique expertise and experience which has enabled them to refine their delivery models and processes to drive down the cost of Passivhaus. This is reflected in the reduction in the cost premium for Passivhaus from 20 per cent in 2009 to 4 per cent cost saving, pre-covid for apartments up to 4 storeys based on the cost plans against Building Regulation compliant low-rise apartments. Currently due to the rise in material costs during and post the pandemic, we have not been able to evaluate the current cost premium. However, current projects do not anticipate any passivhaus cost premium and indeed there is potential for cost savings, depending on the design and the passivhaus knowledge of the delivery team.

Lessons learned

Much has been learnt by Exeter over the years but there are three key areas to focus on; The Project Brief & Design, The Procurement Process and Construction & Delivery.

The Project Brief & Delivery is the most critical stage for ensuring Passivhaus delivery success and it is vital to appoint the right project team with both Passivhaus qualification and experience. Exeter City Living offer the services of their Team to other Councils keen to adopt Passivhaus. It is also important to ensure that Passivhaus is clearly stipulated as the performance criteria for the development and a cost plan developed that reflects this.

Choosing the right procurement and contract route is also very important ensuring that there is realistic risk sharing between Client and Contractor. The selection of Contractors should be on quality as well as cost and a collaborative approach adopted from the start.

Finally, ensuring that there is a realistic programme to successfully deliver a Passivhaus project is key, with due regard to work sequencing, interim air-testing and the robust on-site quality assurance.


Gary Stenning: [email protected]

Emma Osmundsen: [email protected]