Technical Area | Articles

If BIM and the digital model are widely adopted in new buildings,
their implementation in the renovation, rehabilitation projects, or
simply for maintenance and operation of buildings is not easy. First,
you have to capture reality using laser scanner technology and then
proceed to model the survey to a digital model.

Why use 3D scanners?

Because it is estimated that a survey is 5 times faster than the
traditional method, 3D scanners are today the optimal entry point for
the creation of a digital model of the existing one. Whether stationary
or mobile, scanners project a laser in all directions around its axis to
detect the distances from each wall. Different models exist with prices
varying with more or less important levels of precision. 3D scanners
are the most efficient and reliable answer for digitizing a building. In
fact, unlike 2D plans, which very often prove to be obsolete, these
machines carry out a survey of the “as-built”, taking into account all
the peculiarities of the structure. From a scanner report, it is then
possible to carry out several deliverables such as digital plans/models
(interiors, facades, etc.), but also area calculations. The statement
thus represents an excellent basis for technical or legal studies.

The BIM digital model made from a 3D laser scanner
is becoming more common in real estate recognizes and a growing share
of professionals are using scanners. By integrating information from the
diagnosis, such as the presence of asbestos, it allows a better
understanding of the building by the contracting authority and
represents real added value for the services of the recognizer. This is
particularly the case for social landlords whose number of tenders in
this direction is increasing.

What are the steps to follow for a successful scan?

If you want to digitize your assets in order to create a digital
model, you must either acquire or rent a scan, or call on a service
provider (surveyors, scanning companies, etc.). The scanner reading can
be done in any type of infrastructure, empty or not, but the time spent
scanning will be more or less high depending on the space requirement.
The site survey then generates what are called point clouds:
three-dimensional georeferenced coordination points.

These point clouds are then merged to obtain a single file, which
must be reprocessed, “transferred”, manually using dedicated CAD
software in order to create a digital 3D model.

What are the limits of this method and the solutions?

The main limitations of the scanner survey are, on the one hand, the
price of the equipment, which is certainly constantly falling, but which
still represents a significant investment, especially for small
structures. This is why the rental option can be a solution if you want
to internalize this skill.

On the other hand, laser scanner technologies are able to capture
only what is visible. To digitize networks, for example, remove false
ceilings.

The result of this reading is represented by a point cloud, which
itself contains thousands or even millions of points. Given the large
amount of information it contains, this file is often very large, which
makes sharing and storage restrictive. The typology of the building also
largely influences its weight. For example, the point cloud of a
21,000m² high school building can weigh 120 GB. Also, reprocessing a 120
GB cloud on CAD software is tedious and requires a machine with
significant computing power.

But don’t worry too much about it! Archdraw Outsourcing
has vast experience of building information modeling to build 3D models
from point cloud data. We have an expert team for accurate and high
quality 3D modeling services.

Archdraw Outsourcing: Scan to BIM Services.