Early energy calculations crucial for sustainable construction

With the increasing focus on energy and climate issues, there is a growing interest in how best to build more energy-efficient buildings and also to adapt existing buildings to climate change.
- "The energy issue affects all parts of the building and the earlier in the process the issue is raised, the more likely we are to achieve really good results," says Helena Bülow-Hübe, environmental and energy manager at FOJAB.

FOJAB has been offering specialist expertise in energy calculations since 2011 and today the demand is greater than ever.

- When the Swedish National Board of Housing, Building and Planning changed its regulations in 2006/2007, the industry became seriously aware of energy issues. Since then, new requirements for energy and environmentally certified buildings have driven both knowledge and willingness to act. Today, many clients want to build more energy-efficiently than the building standards require - a very positive development. The recent energy prices have of course also increased the focus on the subject," says Helena.

Light penetration versus indoor climate
Headed by Helena Bülow-Hübe, FOJAB offers a range of services - from energy coordination, energy calculations and advice to specialized calculations such as daylight, indoor climate and thermal bridges.

- The architect's 3D model of the building is an important basis for our work. It allows us to evaluate a variety of things, such as how much daylight is let in and how the solar heat will raise the temperature in different rooms, but also the building's total energy use and climate impact based on different material choices," says Helena.

Today, many people want generous amounts of light, which can conflict with a building's energy performance and a comfortable indoor climate. In simple terms, a window emits ten times more heat per square meter than a wall surface. However, they also let in solar heat, which means that large windows can create heat problems and unhealthy indoor temperatures in summer.

Climate change adaptation against heat waves
- This is a problem that will be accentuated with a warmer climate. This became clear not least during the hot summer of 2018 when an excess mortality rate was observed," says Helena.

She has noticed a marked increase in interest in climate adaptation of housing in the existing stock. Together with the City of Helsingborg's property management, Helena Bülow-Hübe has investigated the possibilities of improving the indoor climate in nursing homes and LSS homes so that they are better equipped for new heat waves. Both existing solar shading and the possibility of introducing cooling in existing buildings have been reviewed.

- "We don't normally cool our homes today, but it's starting to be discussed more and more, and in the long term it may come. It is sensitive, of course, because we have clear energy requirements. Comfort cooling will increase energy demand, which may have to be compensated for in some way. Some players have already introduced cooled supply air in nursing homes, while it is not so common in ordinary apartment buildings. Part of our mission, both in terms of new construction and climate adaptation, is to provide advice on windows, glass and solar shading in order to solve this problem, as well as various conflicting requirements.

Cost-effective early decisions
Energy coordination is about controlling and managing the energy work so that the building actually achieves the energy targets set by the client. A wide range of decisions must be made during the design phase, many of which are directly related to the future energy performance of the building. These can range from insulating the cold outdoor and exhaust air ducts that run in shafts through the building, to how windows should be fitted or how much insulation should be placed beyond the edge of the floor. Details that create larger or smaller thermal bridges depending on their design.

- Seemingly small details have a huge impact on the end result, something that designers and project managers don't always think about. That's why it's so important that we get involved early in the process. With our expertise, construction companies can avoid expensive rework later on, and when decisions are made at the right time, they don't always have to increase production costs," says Helena.

Interest in niche knowledge is growing
Helena Bülow-Hübe is a civil engineer and has a PhD from Lund University on the subject of windows and energy balance. In addition to assignments for FOJAB's customers, she is also a frequent lecturer at Swedish Energy Education.

- Here you can really see how interest in these issues is growing. In 2021, we decided to hold a course on "Cold bridges in energy calculation and design", but because the topic is so niche, we thought it would attract quite few participants. This year we are holding the course for the eighth time and all sessions have been fully booked.

- "I think this is due to an increased awareness in the industry and a great willingness to plan ahead. People know that new requirements are coming - not least in connection with the EU's green taxonomy - and they want to be prepared and increase their knowledge of sustainability and energy planning in various ways," says Helena Bülow-Hübe.