CIBSE AWARD WINNER | WARM WARMS SHAPE TOOL been shown that, once it becomes normal, there is no real relationship between building energy performance and build cost, she says. Most contractors Warm works with are keen to learn about Passivhaus. We provide a lot of support to contractors and builders who are trying to build low-energy buildings, and to make them airtight, says Godber. She says most contractors have an exceptional attitude because they see Passivhaus as an opportunity for them to prove that they can do a good job its not technical, its just about building really well. Becoming a client We like having a go at making tools, as you can see from the download page of our website, says Godber. If there is something interesting that weve developed, we tend to share it with everybody. Warms Shape Tool is aimed at architects to help them with the early stage massing of housing developments. It allows the architects to get an idea of how much insulation they need and how efficient the form of the massing is from an energy perspective because heat loss is a function of surface area, Godber explains. So, if you dont want to spend money and embodied energy on fancy insulation, build a simple shape; simple buildings tend naturally to have fewer fiddly details and dont require fancy materials to make them work, says Godber. Warm had a chance to put into practice its low-energy credentials and contractor support mechanism when it decided to refurbish its offices to Passivhaus EnerPHit standards. To get a proper understanding of the issues faced by contractors and clients, there is nothing like doing it for yourself, Gober says. One of the lessons learned from the experience was how difficult it was to fit the rigid external insulation it had specified onto the offices rough faade. Warms EnerPHit proposal had to be certified by an independent consultant. You cannot certify your own scheme, so we got another independent certifier to certify the design, says Godber, adding that it was a positive experience. There is nothing like having someone check your work there is so much going on when youre designing a project that you might miss a way to improve the performance of a particular detail, which the certifier will point out. Knowing that someone is checking it is incredibly valuable. It makes a big difference to how a scheme will perform in practice. If we want good quality buildings, we need to invest in a good quality assurance system, she adds. One of the biggest lessons Warm learned from the experience of working on its own offices is an understanding of how difficult it is to make decisions as clients. When youre just focused on the Passivhaus, you only see things from one angle what theyve chosen is not the optimum but, sitting on the clients side and having that compromise experience, you can understand and empathise with them, says Godber. You come away feeling incredibly humble towards other clients and the compromises that they have to make, she says. Working on its office build, combined with Warms experience of working with contractors and its post-occupancy monitoring of lowenergy projects, has given a good understanding of the practical side of implementing design solutions. The big thing weve found from site support is the need to simplify everything, says Godber. Warms post-occupancy monitoring has also highlighted how little maintenance goes on within buildings. Whatever your solution, make it simpler still for ease of use, maintenance and buildability, says Godber. Warm passes on its acquired low-energy and Passivhaus knowledge through the training courses it runs. Weve always been surprised by how few building services engineers are interested in our training; its a shame because it complements their skills perfectly, and is a huge opportunity for them to pick up this knowledge, Godber says. We would like to see greater participation from building services engineers in Passivhaus projects because, if they do get on board, the project will really sing, she adds. Godber warns people to be wary of schemes described as designed to PH principles. Anything can be claimed to be designed to Passivhaus principles for example, they might have put loads of insulation on and claimed the scheme is Passivhaus, or they might have been really diligent and built the scheme correctly, you just dont know, she says. The only way to be sure it is a Passivhaus is to ensure it is certified as such. CJ Warm provided Passivhaus consultancy for 72 homes in Primrose Park, Plymouth 32 September 2019 www.cibsejournal.com CIBSE Sep19 pp28-30, 32 Warm.indd 32 23/08/2019 16:26