Passivhaus vs. Creativity
By Sophia Barker
28 November 2019
Earlier this month, our Bristol office co-hosted a talk with Feilden Clegg Bradley Studios about "Passivhaus vs. Creativity".
I spoke alongside Nick Hodges from Feilden Clegg Bradley Studios about the opportunities of Passivhaus, its context in the climate emergency and how Passivhaus can be achieved.
Following the event, Nick and I produced these notes on the presentation and the discussions - I hope you find them interesting and helpful.
You can see the slides from the event here.
- In the context of Architects Declare, Engineers Declare, the climate emergency and the intense need to reduce carbon emissions to net zero, Passivhaus appears to be a key player. If we want to meet expected available renewable energy by 2050, Passivhaus seems the best established approach. Passivhaus buildings allow a future that can be fully reliant on renewable energy.
- The words we associate with Passivhaus can give us false ideas about the standard if we don't fully understand their meaning. Passivhaus can be considered to have a relatively narrow focus: on energy consumption and comfort. For a more complete view of sustainability Passivhaus should be used in parallel with other systems. FCB Studios work within a broad One Planet Living framework, which includes net zero carbon, water use, social sustainability, zero waste and ecology. On Croft Gardens the Sustainability Matrix developed by Max Fordham is being used, which is a bespoke set of targets set in line with the project’s specific ambitions and aims.
- We don't have enough renewable energy to supply all of our buildings unless we reduce demand to Passivhaus standards - improving the fabric performance of buildings is critical to becoming sustainable.
- A benefit of Passivhaus is that it allows thermal performance to be part of the conversation as a quantified entity. Passivhaus puts more rigour in to the modelling and evaluation of thermal performance, so the challenge is for design teams to find ways of creating good designs within these parameters. How we view this constraint impacts on how well the design works.
- Without good architecture, Passivhaus buildings may perform well but run the risk of lacking in inspiration. We need to build skills in this area so that high performance and beautiful architecture can both be achieved.
- Going for Passivhaus certification has distinct advantages, through monitoring work on site and at post-completion. There is often a level of enthusiasm and spirit throughout the site team that is harder to quantify, and many of those involved feel they are really making a difference in terms of climate action.
- The PHPP model is central to the process, and seeks to bring the MEP system and fabric together to create an efficient building. It is also very effective in predicting in-use energy, which can be important for forward planning – for owners, estates departments, local authorities and tenants. An accurately predicted, low-energy building is also less exposed to variations in energy rates, and for many households this creates a beneficial resilience. Once a building is built, the building users don't have a choice on how much heating or cooling it requires for comfort, this is a fixed outgoing. We hold responsibility for reducing our reliance on energy prices.
- It is vital that the whole design team collaborates and shares information; working together within the PHPP model as a team can be really effective.
- It is possible to achieve Passivhaus for other building typologies beyond housing, and there are examples of completed projects in schools and higher education. If we embrace what Passivhaus wants and fully understand the opportunities and constraints, it is possible to have efficient, interesting and beautiful outcomes.
- For Passivhaus to become mainstream support is needed from government policy. This will bring its own challenges in terms of educating the industry and monitoring to ensure that the buildings are built as designed.
- Planning departments can sometimes be a hurdle to achieving an easy/cost effective route to Passivhaus. Educating Planners on the reasons why Passivhaus creates better spaces to live is an action to undertake.
- Embodied carbon is also an area where we hold responsibility for reducing carbon emissions and mitigating climate change. For Passivhaus buildings, where in-use energy demand is so low, embodied carbon becomes a large proportion of the overall energy demand of the building over its life.
- From our experience Passivhaus is broadly within budget expectations and as teams are ‘upskilled’ across the design and construction teams Passivhaus projects should be deliverable to the same programmes and cost envelopes as other, similar, buildings.
- For many, the climate emergency feels beyond their control and Passivhaus could be considered empowering at a personal, community and institutional level. It is synonymous with progressive standards, and our experience is that those engaged in Passivhaus projects are proud to feel they are contributing to action on climate crisis. As local authorities and housing associations increasingly take a lead in delivering low energy buildings, we hope that increased public awareness sees approaches such as Passivhaus become more commonplace.
- Does Passivhaus stop creativity? We don’t believe so. It is a further input into the design of a building; another challenge within the creative process, alongside site, budget, brief and the planning context.