Passive House design needs no introduction in Exeter. The small city of approximately 130,000 located in South West England has long been one of the leaders in Passive House building in the UK. This front-runner status is largely due to the work of Exeter City Living, a profit-for-purpose limited company owned by the Exeter City Council that serves as the council’s development arm. To date, the Council have created approximately 200 housing units that have been certified by PHI and are even responsible for the development of St Sidwell’s Point, the first leisure center in the UK built to meet Passive House standards. The center is expected to open in early 2022.
According to Emma Osmundsen, Exeter City Living’s managing director, the group was initially drawn to Passive House in the late 2000s as a means of eradicating fuel poverty. Though she admits that many on the team were somewhat skeptical about how dramatically the building methodology would cut energy use, they decided to move forward with the plan. In 2008, they began construction on what would become the second Passive House project in the UK and the nation’s first certified multifamily structure.
Completed in 2011, Osmundsen says that the first project cost approximately 20% more than a code-built structure. However, Osmundsen says the tenants used less energy and were able to rise out of fuel poverty. In addition to using less energy, the residents had more disposable income, which has reduced rent arrears and enhanced support to the local economy. Many have reported health enhancements too.
Fast forward to today and the initial cost premium has vanished. Osmundsen says that she can now build Passive House apartments for 3% cheaper than their code-built counterparts.
Design that Caters to Residents
Exeter City Living is not the only Passive House all-star on the Edwards Court project. Architype, one of the UK’s leading sustainable architecture practices, was responsible for the design of the 53-unit scheme—43 one-bedroom and 10 two-bedroom. From the first stages of the development the firm was guided by the intertwined principles of building biology and Passive House. Building biology prioritizes human-based design, fostering community within the building and beyond its walls, sustainable environmental performance, indoor air quality, and thermal and acoustic comfort among its 25 principles. While these principles are not exclusively focused on improving building performance, as is the case with Passive House, design that is informed by Passive House principles allows for the realization of building biology’s aims. Airtight construction and mechanical ventilation provide optimal indoor air quality. Superinsulated envelopes, high-performance glazing, and thermal-bridge-free detailing inevitably result in thermal and acoustic comfort (see Figure 1). Meeting Passive House building performance targets is foundational to crafting ecologically sound developments.