Working in a BIM environment can bring many benefits to both Clients and their project
teams – and as you’ve probably started to realise, those benefits can extend to Cost
Managers too.
In this video we’re going to talk about 5D BIM, explaining what it is and how it can
help you.
To give you a quick refresh, BIM is the process of creating information models or data sets
formed of graphical and non-graphical information in a shared digital space known as a Common
Data Environment (CDE).
The information builds in richness as the project stages progress until that complete
data set is handed over to the Client at completion.
As you create an information model, you can add scheduling data to different components,
generating accurate programme data for your project.
This is known as 4D BIM.
The next step is to produce accurate cost estimates from the components of the information
model and it’s this process that is known as 5D BIM.
Those estimates can consider the capital cost of purchasing and installing a component,
the running costs associated with it once in use and the anticpated price of renewing
it in the future - all based on the data and information associated and linked to that
particular component.
With the graphical model and its attribute data developed, Cost Managers can very quickly
determine the quantity of a particular component, applying rates to those quantities to reach
an overall cost for that package.
Those packages costs are then combined to build an overall picture of a project’s
cost.
Counting can be done automatically, saving time and patience; you can see what you’re
costing clearly in 3D form; and you can be automatically notified when changes are made
in the information model.
It’s relevant to those purely involved in the delivery phase on site too.
With solid 4D programme data and a robust contract sum, you can track predicted and
actual spend over the course of your project, which is really useful for monthly cost reporting
and budgeting.
One important point to note is that ‘5D BIM’ refers to a particular way of linking
data to an information model – an additional dimension if you like of data.
It is quite different to the BIM maturity levels that run from 0 to 3 (and beyond) describing
the supply chain’s ability to exchange information in a digital way.
4D, 5D and 6D considerations can all occur within BIM Level 2.
If you’re working with 5D BIM, it would be wrong to say that you’re working at “BIM
Level 5”.
As you can probably tell, the quality of your cost estimate is directly linked to the quality
of the data produced by the rest of your project team.
If that is wrong or inconsistent, errors can be carried forward into costing.
That is no different to the traditional approach of delivering buildings.
And that’s a perfect point to dispel a rather scary myth.
In our long established industry a lot of time and effort goes into producing accurate
cost estimates by some excellent people, and it’s only natural that those people are
going to question their futures when hear about this 5D BIM concept for the first time.
But they really don’t need to worry.
Because Cost Managers – whether they’re Estimators or QSs – are essential for validation.
Because not everything in a building information model is going to be right.
For starters not everything is always modelled in 3D and there can be a lot of 2D information
used – some elements aren’t even modelled at all.
You’re just supposed to know that they’re there.
Added to that is the fact that different models may classify things differently.
Floor areas for example might be in Gross Internal Floor Area (GIFA) or Gross Internal
Area (GIA) format, and they may or may not include voids.
This all needs clarifying by the Cost Manager.
Earlier we described a very simple form of quantity counting or take-off, but essentially
there are three types of quantity in a building information model.
There are quantities based on actual model components that you can see the size and details
of in the model.
The 5D technique is great for getting costs on these elements.
Then we have Quantities derived from model components – such as architraves around
doorways for example – that you can’t always see.
And there’s Non-Modelled Quantities – things like temporary works, construction joints
in slabs, shoring etc.
Unless the construction phase itself is fully modelled, the designer’s graphical model
will indicate design quantities – not construction quantities.
Types B and C can only be picked up by an experienced Cost Manager.
Currently Cost Managers might produce an indicative cost plan at the outset of a project and then
update it once or twice as a project develops.
They only cost completed designs at the end of a long iterative chain when their project
team have finished designing.
In a BIM process, Cost Managers are engaged right from the outset and are an equal player
in the project team.
Their time is freed up from painstaking manual take-offs in the later stages and used in
faster, more accurate cost reporting up front at a much more influential stage.
They effectively maintain a ‘living cost plan’ and become invaluable in helping their
teams design to budget.
So for Cost Managers 5D BIM represents less work for you – but please don’t panic
and think less work is going to translate into downsizing – its less work but done
more often, on net it’s the same amount of work and your contribution is going to
be more highly valued by your colleagues and project team peers.
And here’s the really key thing: Cost Managers, whether they are Estimators or QSs, are actually
going to become more valuable as a result of the 5D BIM process.
So, I mean like, don’t tell anyone about it, but I think you’re probably due a pay
rise as a result of getting involved in 5D BIM.
Really sorry I’ve said that on YouTube for any employers out there, but, you know, it’s
about time.