As-built documentation of a historic building on Horní náměstí, Olomouc

A historic mixed use building in the centre of Olomouc, with two basement levels, five floors above ground and an attic. Garages sit in the basement, a café and an entrance hall on the ground floor and individual rooms on the upper floors. We recorded the existing condition of the whole building with a 3D laser scanner, built a Revit model on top of the point cloud and produced the drawings and the written part of the documentation. Utility existence statements from five network operators were part of the commission.

The subject of the commission was a multi storey historic building on Horní náměstí in the centre of Olomouc, in mixed use. It has two basement levels, five floors above ground and an attic. Garages are located in the basement, a commercial unit with a café and an entrance hall on the ground floor, and individual rooms on the upper floors. The aim was to document the existing condition of the whole building and to add records of the underground utilities around it.

Interiors and structures were captured by 3D laser scanning. The result is a point cloud, a spatial record of the building that dimensions and positions can be taken from at any time. A BIM model in Revit was built on top of that data and the drawings were generated from the model. Geodetic survey work and a photographic record of the building were part of the site work. In parallel we requested utility existence statements from five network operators, covering telecommunications, gas, electricity and water infrastructure. All five arrived between 7 and 10 February 2025.

The first complete set of the written and drawing parts is dated 18 and 19 February 2025. A revised technical report followed on 2 April and a further revision of the drawings on 31 May. The consolidated PDF package is dated 2 June 2025, so active work on the commission ran for roughly four months. The documentation is structured into a cover sheet, a summary technical report, a site plan and a drawing part, which follows the usual make up of Czech documentation of an existing building. A set like this serves two purposes. It is a basis for further design work and it records the condition of the building at the date of the survey.

Project challenges

Scale is the main issue here. Two basement levels, five floors and an attic add up to eight levels stacked on top of each other, and a building like that cannot be captured in one pass. The scans have to be tied into a single coordinate and height system. Otherwise every single floor plan looks correct while a section cut through the whole building does not line up.

Older buildings in a city centre add another factor, because they were built and rebuilt in stages. Walls are rarely straight, the layout changes from floor to floor and the staircase is often the only element that runs through the full height. Staircases and shafts therefore decide whether the model holds together vertically. The second theme is the coordination of underground utilities. Each operator issues its statement separately, in its own format and its own time, and the surroundings of the building cannot be described in full until all five are in. In this case all of them arrived within four days, so utility coordination never became the bottleneck.

Project deliverables

• Cover sheet and summary technical report (parts A and B)
• Site plan (part C.1)
• Drawing documentation (part D): schematic floor plans from the first basement level to the attic, sections, elevations and a roof plan
• Point cloud from laser scanning (LAZ, RCS)
• BIM model in Revit
• Utility existence statements from five network operators
• Consolidated PDF package of the complete documentation