“The virtual design and construction solutions familiar from new construction can be applied to existing sites as well,” Sipilä says. This so-called inventory twin is a smart 3D model that provides up-to-date initial data on the dimensions, amounts, materials, and locations of existing buildings.

“This ensures the controlled and disturbance-free execution of projects,” Sipilä states. Accurate initial data also maximises the amount of material that can be recycled and creates value to waste as recycled material.

The inventory twin offers great benefits early in the project when the most cost-effective implementation methods are being discovered. “We create an appropriately accurate inventory twin for each case and act as the client’s partner throughout the project, as needed,” Sipilä says. Sweco’s specialists can take care of the design, demolition surveys and permit issues, for example.

Inventory twin supports decision-making

Information models are rarely available for old sites and drawings can be unavailable or unreliable. This means that the initial data verified by the inventory twin is already essential in the tendering stage of modernisation and demolition projects.

“Reliable initial data allows us to draw up more accurate offers faster and with less work,” Sipilä says. “Risk management is also enhanced, for example, if the 3D model is supplemented with detrimental material study results.”

In addition to the initial data, the inventory twin illustrates the information provided by the plans and demolition surveys transparently to different project parties. “When all parties understand the issues better, decision-making becomes faster and the project moves forward with less surprises.”

Inventory twin created with laser scanning also supports maintenance

The building to be modernised or demolished is first scanned with a laser. The point cloud received is used to create an inventory twin that contains the structural elements of the site, as well as the dimension, amount and material data.

“The inventory twin is a tried and tested method of illustrating facilities, structures and equipment in industrial site modernisations,” Sipilä explains. “The same safe and cost-effective operating model can be applied to demolitions as well.”

Once the modernisation has been completed, the inventory twin can be updated and used for the purposes of site maintenance and future renovations or even in VR/AR environments. “The benefits of the inventory twin are emphasised in clean spaces, for example, where the number of people making measurements or interrupting production needs to be minimised.”

The benefits of the method are highlighted, especially, in projects with great geographical distances. “The visual 3D model enables safe remote interaction and stakeholder meetings in the virtual environment,” Sipilä emphasises. “Travelling to the site is no longer necessary.” Different design fields can also utilise the inventory twin in their work.