It’s always useful to have practical examples of how BIM can provide real benefits. Managing penetrations, that will require firestopping, through fire compartment walls is one example where BIM can improve your workflow, save time and money, but more importantly enable the construction of a safer building.
All penetrations through fire compartment walls should be firestopped to provide a safe building by preventing the spread of a fire.
Traditionally, firestopping of penetrations would be lumped together as ‘builderswork’. Which is a term used to describe work that doesn’t neatly fit within a subcontractor package.
When tendering for a project an assessment of firestopping is made by either applying a simple rule of thumb percentage of the overall project cost or using approximate quantities by comparing 2D M&E and architectural plans.
Many projects now have a combination of architectural and M&E models. By assessing the two models, we can produce a detailed and precise schedule of firestopping. This reduces risk by ensuring that the allowance for firestopping is correct, it assists with procurement and also enables the installed firestopping to be monitored, tracked and audited.
We used the following information and tools to produce a schedule of firestopping:
The steps required to produce a firestopping schedule:
Now running through each step in a little more detail.
Using simplebim we select the fire compartment walls.
Ideally, the architectural model contains defined parameters for fire rated walls. If the walls contain a fire rated parameter, it will make selecting the compartment walls a much simpler task. Without this information, you will need to compare the model with the fire strategy information and then select the relevant walls.
You should also be satisfied with the quality of the internal walls model. Internal fire compartment walls should extend to the underside of slabs or floors, to ensure that no penetrations are missed due to the gap between the top of the modelled wall and the underside of the slab.
It’s important to also include the space information with the extracted fire compartment walls. This makes it much easier to identify the location of each penetration.
The extracted data is then saved as a separate IFC model rendition file.
Next, we use Solibri model checker. We need to check the building services model and the extracted fire compartment walls. Both models are imported into Solibri as an IFC file.
If the fire compartment walls are identified as separate and individual objects, it’s possible that you’ll not need to do the first step and extract the information using simplebim. Instead, you could filter the information within Solibri and check only the relevant objects.
You will need a Solibri ‘rule’ to check the model. One of the default Solibri rules ‘Building Services and Other Construction Components’ provides a good starting point. The default rule will need to be altered to ensure that every penetration is checked. The out of the box rule excludes duct or pipe penetrations through walls, this exclusion is easily removed within the rule parameters.
We also amend the rule to explicitly include all the types of objects that we want to check, such as ducts, cable trays, pipes.
It’s then a simple procedure to check the model for penetrations through the compartment walls. This rule will analyse the combined building services and fire compartment model for intersections between the two.
In this example, the analysis identified 125 intersections or penetrations between the building services and fire compartment wall models.
Each of the 125 penetrations are viewed separately and an issue is produced.
Solibri issues or slides combine penetration data, such as the references for the building services and wall components, the spaces and a snapshot of the penetration.
When viewing each issue it’s always beneficial to quickly assess the validity of the penetration. Unless your models have been validated as being 100% correct and you have accurate and suitable data the model check may include false positives. The false positives can be filtered out or flagged during this step.
All of the 125 issues are then extracted in a spreadsheet format. Each issue listing the location where they occur, the components that are penetrating and a snapshot of the issue.
A quick example of an extremely beneficial use of your project models. The excel schedule is used for procuring a firestopping subcontractor, each penetration is priced rather than using either a manual take-off or a percentage of the project value. The schedule then gets reused during the installation and sign-off procedure for each penetration. It becomes supplemented with the installation date, details of the type of firestopping and a photo of the completed firestopping.
This provides a clear and visible audit trail of firestopping, it’s included within the handover information and provides a passive fire register.
Why make assumptions with something as important as firestopping. Fully traceable and auditable firestopping is being used now to benefit construction projects.
We hope that you are able to apply the above process to benefit your project, but, if you need someone to do it for you, then contact us for an instant quote and until the end of January 2018 BIMsense are offering an introductory 25% discount on your first firestopping schedule.
Ian Yeo, BIMsense firstname.lastname@example.org
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