New thermal insulants lower production and transport costs in construction: Business Joensuu tasks Sweco with analysing the suitability of super insulants for energy-efficient construction

The emission reduction goals set by the EU will increase zero-energy construction in Finland. Business Joensuu tasked Sweco specialists with analysing super insulation materials that conserve heat energy along with reducing construction and transport costs. This also frees up more floor area for the buildings.

Zero-energy construction has been being developed in Finland since the 1990s, and the European Union’s goals are in line with these aims. By the end of 2020, all new buildings must be almost fully zero-energy properties that receive their energy primarily from renewable sources.

“Buildings require a constant supply of energy for many things, such as maintaining the interior conditions. In this context, we often talk about zero-energy buildings that produce and consume an equal amount of energy,” says Sweco’s energy specialist Jyri Nieminen. Finland’s first nearly zero-energy building was completed in Jakobstad in 1994, but many solutions, such as solar panels and heat pump systems, have taken massive strides since then, and the same goes for thermal insulation.

“Upon their introduction, the current mineral wool insulants were 5–10 times better than the old sawdust insulants. Now we are taking the next developmental leap by shifting to new kinds of super insulants that are 10 times more efficient than the ones currently in use,” Nieminen says.

Super insulants increase the sellable floor area

Sweco’s specialists conducted an analysis of new thermal insulants and their suitability for energy-efficient construction for Business Joensuu. In addition to energy consumption, the life cycle analysis covered the carbon footprint in the construct and maintenance phases, the emissions of insulant production and the recyclability of the materials.

“We commissioned the analysis from the leading expert in the field because we wanted to be informed of the new kinds of opportunities that super insulants offer,” says Business Joensuu’s Development Manager Timo Tahvanainen. Sweco’s specialists went through all options on the market, such as vacuum insulated panels (VIP) made from biopolymers and silicon.

“The carbon footprint of energy-efficient super insulants is small, and savings are also achieved in transport costs. The benefits are evident especially in industrial construction, where elements are transported from factories to worksites over long distances,” Nieminen says.

One of the most important benefits of super insulants is their superior capability in insulating thinner structures than is possible with current options. This reduces wall thickness, increasing the sellable floor area.

“Our analysis indicates that the use of super insulation materials is worthwhile. Based on current building rights, they increase the floor area by 1–3% compared to typical exterior wall structures,” Nieminen says. “If the building right were to be determined based on the exterior surface of the building envelope, the change would be even more substantial.”

The current Building Act does not encourage the use of super insulants

Energy- and resource-efficient construction will take new forms in the future and, at the same time, construction legislation is in need of updates and new incentives.

“Depending on the municipality, the interpretation of the current Building Act is that when wall thickness is more than 25 cm, the excess portion is not calculated as part of the buildable area,” Tahvanainen says. Originally, the purpose of this interpretation was to support better insulation and thereby more energy-efficient construction. With the new insulation materials, however, the established interpretation of the law becomes counterintuitive. “The practice that is in conflict with the spirit of the law does not favour the use and development of new structures and insulants.”

There are currently a few super insulation materials with a CE marking on the market, but no domestic solutions are available. The market has room for new innovations.

“As an example, super insulants can reduce concrete wall thickness from 50–60 cm to 25–30 cm, which spells a clear decrease in material consumption and carbon dioxide emissions from production. Now all we need is persistent development efforts and entrepreneurs who set their minds to finding a financial feasible solution,” Nieminen says.

Sustainable construction generates new business

The City of Joensuu has an ambitious climate strategy and programme, which is aimed increasing the energy efficiency of the building stock. A new business park focused on the circular economy is also being constructed in the city. As such, one of Business Joensuu’s goals in commissioning the insulation analysis was to find fledgling start-ups and fresh perspectives for high-tech construction.

“The constantly-increasing industrial construction favours wood as a construction material, and Joensuu happens to have the special expertise for the job, along with a complete ecosystem. The shift in the construction industry is also creating new opportunities for the strong concrete industry in the area,” Tahvanainen says.

Sweco’s experts will present the results of the analysis to construction companies in the autumn.

“We want to make sure that knowledge of new technologies reaches the development-oriented companies in the area, and that new industrial investments and production arrangements emerge to strengthen sustainable construction in Joensuu,” Tahvanainen says.

Have you already read Sweco’s Urban Insight reports? This year’s theme is Urban Energy. The efforts to increase energy efficiency are covered in the following report, for example:

Reduce, reuse and reimagine – Sustainable energy development in the City.