Recycling rate of Savo Vocational College’s demolition increased to 92%

The Savo Consortium for Education sets high recycling targets for its demolition projects. At Kuopio campus, they were exceeded when the recycling rate rose to 92%. Resource efficiency was reflected, among other things, in the recycling of concrete rubble, and a significant amount of material was also sold for reuse.

The final stretch of the demolition of the central campus of Savo Vocational College is taking place in Kuopio. The block located at Presidentinkatu 1–3 has been demolished in three stages, and a new vocational college has already been built in Savilahti. Sustainable development is part of the strategy of Savo Consortium for Education (SAKKY), which is why more stringent circular economy targets were set for the demolition project: recycling and reuse rates exceeding 85%.

‘We want to be pioneers in sustainable development when it comes to vocational education,’ says facility service manager Milla Lompola from SAKKY. She stresses that the objectives must also be reflected in practice, and that is why carbon footprints are calculated for all construction and demolition projects. New buildings are also built in accordance with the Nordic Swan Ecolabel. ‘Our aim is to halve the greenhouse gas emissions by 2025 from the 2019 levels.’

Sweco started the demolition project on Presidentinkatu as a developer consultant in autumn 2021. Its responsibilities included planning the demolition work, carrying out demolition surveys, calculating the demolition volumes and conducting surveys on asbestos and detrimental materials. ‘Sweco has been our framework agreement partner, planning the demolition of our educational institutions, for example at the Iisalmi campus,’ Lompola says.

Project Manager Teemu Heiskanen from Sweco feels that a high recycling rate in a demolition project would not be possible if the client and contractor were unable to share the same goals and ambitions. ‘No matter how accurate the demolition surveys are, the outcome always depends on the execution.

The demolition work on Presidentinkatu started in autumn 2022 and will continue until the end of 2023. ‘Now it seems that the work may be finished as soon as this summer, thanks to the flexible cooperation between the operators,’ Lompola notes with satisfaction.

Street construction to proceed alongside demolition work

The location made the planning for the demolition work particularly interesting. The Mölymäki hill offers a view of the centre of Kuopio and the Kallavesi lake, and the adjacent plots have residential buildings, Kuopion keskuskenttä stadium and construction sites. The demolition area has also been zoned for residential development, and the City has begun to build new streets.

‘The demolition work had to be carefully phased and scheduled in coordination with the area’s infrastructure construction so that SAKKY and the City could divide and sell the plots,’ Heiskanen says. The basement facilities were also demolished, so earthworks and restoration of the ground surface were needed on the site.

The demolition contractor Lotus Demolition is familiar with challenging building sites in urban centres. The only thing making Presidentinkatu an exceptional location was the scope of the demolition, 38,000 square metres. ’It’s about six times greater than our typical demolition sites,’ says the contractor’s branch manager, Olli-Pekka Itälä.

The second challenge was the protected commercial college built in 1957, which had to be saved even though its walls were attached to many of the building parts that were destined to be demolished. ‘We often demolish residential buildings that are attached to one another, and therefore saving the protected building was not a problem for us,’ Itälä says. The facades will be restored after demolition.

More than 1,500 lorry loads of aggregate saved

The demolition project on Presidentinkatu exceeded its circular economy goals, as the calculated recycling and reuse rates rose to approximately 92%. Before the demolition, SAKKY was able to sell some of the furniture, machinery and equipment, worth half a million euros, for reuse and recycling. For example, around 100 tonnes of bitumen, 150 tonnes of wool insulation, 1,300 tonnes of metals and an incredible 40,000 tonnes of demolished concrete and bricks will go to recycling from the demolition site.

‘Concrete will be crushed on site as recycled raw material, suitable for construction use in building roads and streets, among other things,’ Heiskanen says. Material efficiency will save more than 1,500 lorry loads of virgin natural rock and soil. Furthermore, the transport costs and emissions will decrease as rock and soil no longer need to be transported back and forth

The careful sorting of materials on site is worthwhile, and the amount of actual construction waste from Presidentinkatu will account for less than 2% of all the demolished materials. ‘It mainly consists of furniture and plastic carpets removed when demolishing the indoor areas, as well as waste plastics, wood and wool that are difficult to sort with a machine,’ Itälä says. They will also go to sorting and be used as recycled fuels.

Lotus Demolition also measures the carbon footprint of the demolition site, which is negative, i.e. -271.82 CO2e tonnes, according to the advance estimates. Follow the carbon footprint of the demolition work on Presidentinkatu in real time on Lotus Demolition’s website.