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Last Updated on 25th April 2022

Scanning behind a dropped ceiling using mobile LiDAR

Surveying buildings is difficult and accessing hard to reach areas, like dropped ceiling or raised floors, without disrupting business can be seemingly impossible.

Over the years surveyors have added new technologies to their toolkit, improving their workflows and tackling these issues cost effectively. From distometers to terrestrial laser scanning, measuring large areas has become easier, faster and more accurate. However, capturing difficult to reach spaces like dropped ceilings is still a disruptive, costly, and extensive task – until now.

In this blog we’ll discuss how SLAM and LiDAR technology has made scanning behind dropped ceilings a simple process.

What is a dropped ceiling?

If you’ve visited a modern-day office space, hospital, school, or retail unit recently, you’ll have likely been stood beneath a dropped ceiling. First used in Japan in the 14th century to add aesthetic appeal and value to a room, dropped ceilings have been commonplace for over 800 years.

A dropped ceiling is a secondary ceiling below the main structural ceiling. Though dropped ceilings are used in most buildings, they’re recognisable for their grid tiled design in professional spaces like office buildings. They cover industrious parts of a structure like air conditioning, pipes, and electrics – functional and aesthetic.

The easily removable tiles make for quick access to the main structure of a building, for repairs or general maintenance of lights, air conditioning or electrics in general.

dropped ceiling showing wires

Looking behind a dropped ceiling

There are several reasons a surveyor needs to measure behind a dropped ceiling, but no simple way to achieve this. Often to reach these you need to remove the dropped ceiling or manually inspect behind ceiling tiles. In a large space, this could take days. Both solutions are disruptive to a working day and could make inspections more hazardous than they need to be.

Here are some reasons why a surveyor would want to look behind a dropped ceiling:

Fire risk surveys

Compartmentation surveys often require comprehensive inspections in difficult to access spaces, like ceiling voids, to assess a buildings passive fire protection.

Office Space

Architectural changes

When a business wants to extend their office space, they are likely to need a detailed and accurate review of what is behind the dropped ceiling, whether that’s air conditioning units, electrics, or general pipes.

How laser scanning helps map difficult to reach areas without the need to deconstruct floors and ceilings

SLAM laser scanning has become more commonplace in a surveyor’s toolkit. It has made measuring difficult to reach areas like dropped ceilings a less daunting task.

Static scanning requires a temporary removal of a dropped ceiling, whereas mobile laser scanners are elevated above a small number of removed tiles. As a result, the solution captured the relevant information needed without significantly disrupting business. Furthermore, the speed a SLAM laser scanner can capture data means mapping difficult areas is made much more efficient.

How GeoSLAM helped Turner Construction map behind their dropped ceiling

Turner Construction needed to carry out a revamp and extension of their Atlanta office. They chose to utilise a SLAM scanner to map behind their dropped ceilings. No 3D model exists of the above-ceiling conditions. The team knew that relying on conventional methods would simply take too long.

Deploying GeoSLAM’s ZEB Revo SLAM scanner and extendable pole accessory, the team were easily able to map the ceiling void.

The mobility of the GeoSLAM unit allowed us to eliminate almost all occlusions which saved time on the modelling because we had a complete picture instead of having to interpolate between shadows that are usually seen in terrestrial scanning.
Turner Construction

Traditional techniques would have taken an entire 8-hour working day to complete, but laser scanning only took 10 minutes.. Relative accuracy of surfaces was more than sufficient to create the BIM model they needed from the data.

Why choose GeoSLAM?

GeoSLAM’s hardware is designed with speed, accuracy and ease of use in mind. Easy solutions for previously difficult jobs. Coupled with our software, GeoSLAM Connect, point clouds generated by our ZEB Horizon and ZEB Revo RT scanners have a relative accuracy of up to 6mm.

Additionally, the versatility and lightweight nature of our scanners make them ideal tools for capturing previously difficult areas to map.

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