3D laser scanning (point cloud scan) is a way of capturing and existing structure in a format that can ve converted into a 3D Revit model. When refurbishing an old building, retrofitting MEP systems is an essential opportunity for MEP engineering design teams to improve the reliability and life cycle of the MEP systems and reduce energy consumption. The significance of the structural and architectural elements is the key to the planning of MEP systems, hence the need for the most accurate model possible. There are aspects which are important to consider when developing M&E models within an architectural model that is created from a point cloud laser scan for refurbishment projects:
Record/as-built Drawing vs. Point Cloud Model.
While most clients may assume that it is sufficient to use a record or as-built drawing for refurbishment, what works better in reality is quite contrary. Creating a 3D model from record drawings is risky in a refurbishment project. Record drawings typically provide as-built specifications of the building that may not necessarily include updates and changes to the building structure.
This creates a problem for M&E modellers, who are working on the refurbishment project, as they may be planning for services that will not fit into a riser, plant area or roof void. This issue is addressed by laser scanning the entire building to develop a point cloud model to map the building as it is in its current condition including all the changes and updates that may have occurred over its lifetime.
Mapping Existing Systems
When a building is being completely stripped, the existing MEP elements are not usually added to the base (existing) model that is created from the point cloud data. However, if some of the existing MEP systems are necessary for the new building then a laser cloud model will be used to model existing MEP systems for onward use along with the architectural model.
In such a case, prior to starting a refurbishment project, together with existing and proposed structural and architectural models, all MEP system components that will be retained must be mapped out in the model. This will then provide MEP engineers with an idea of the constraints that they must work with when developing an MEP model for systems that need to be added to the building.