13 July 2018
LOD: Find Your Level
LOD. Three unassuming little letters that are currently causing big confusion for trade contractors and providers of Building Information Modelling, or BIM for short. So what is LOD? Brace yourselves dear readers, this takes some explaining…
Within the BIM universe, LOD stands for Level Of Development. However, another term regularly bandied around in BIM is Level Of Detail, creating acronym anxiety all round. To make matters worse the two terms are often mistaken for each other – not surprisingly – even though they describe different aspects of a model element. Lost yet? You’re not alone.
Thankfully NATSPEC, the National Building Specification not-for-profit, has undertaken the heroic task of compiling and maintaining a National BIM Guide for Australia. This is a suite of documents that has a red-hot go at defining the roles, procedures, approved software and documentation standards involved in implementing BIM on a project. Light bedtime reading it’s not, but it is a valuable resource for the Aussie construction industry, providing such useful nuggets as a Project BIM Brief Template to download.
Another useful NATSPEC document is a paper that focuses on the term LOD, explaining the concept of Level Of Development and acknowledging the confusion with Level Of Detail. In this paper NATSPEC recommends only ever using LOD as short-form for Level Of Development, which it describes like this: “LOD is a means of defining the extent to which model elements have been developed, from conception in the mind of the designer through to their construction and operation.” Alternatively, they say, “Use [the full term] Level Of Detail to describe graphic detail only.”
The way we interpret this at Drawable is that LOD primarily refers to the amount of data or information within an element in the model. If we’re talking an electrical Revit model, an element could be a distribution board, for example. At LOD 100, the only data that element would have is the description “distribution board”. LOD 200 could also state its preferred dimensions, LOD 300 might expand on its physical description, while LOD 400 would specify a particular board and comprise data such as its manufacturer and model number for ordering. LOD 500 comes at as built stage and would cover every bit of information deemed useful by the client, including purchase date, serial numbers etc for warranty and maintenance purposes.
Another important point NATSPEC makes is: “LOD should only be used to describe model elements” – i.e. your distribution board – “not models as a whole.” But customers talk about LOD as if it’s referring to the whole 3D model all the time, don’t they? Well, in that case, NATSPEC says to assume that “all individual model elements are at least of that LOD”.
“Graphic Detail” or “Level Of Detail”, on the other hand, we at Drawable interpret to mean what the representation of that distribution board actually looks like on the model. At its most basic this could just be a rectangle, whereas if we’re going to get totally fancy it could be a realistic illustration. The important thing to note here is that LOD and how pretty the element looks do not always coincide (although LOD 500 elements do tend to look schmick). However, unlike with LOD, there is no universally recognised grading system for Graphic/Level Of Detail. Which sucks.
Here at Drawable, we have a fiendish plan to overcome all this confusion and have devised our own one-page Revit Specification Sheet, that enables us to glean close to all the information we need from our Revit/BIM customers. Following the KISS Principle, we avoid asking our trade customers to nominate LOD and instead use the more familiar terms of Shop Drawings, Revision Changes and As Builts. We will then work out the true LOD required when we get the full brief. Similarly, we’ve come up with our own ‘grades’ of graphic detail: Basic, Defined and Realistic. Of course one single-page form can’t cover all bases in the complex world of BIM, but we’re quietly confident it’s a sound start.
So if your contracting firm is new to BIM and LOD is making you think WTF, get in touch with a Drawable draftsman and we’ll give your Revit 3D models some TLC.
Drawable’s expertise has been invaluable for the BIM coordination of the Sydney Opera House Function Centre upgrade. I wouldn’t hesitate to recommend them.
Patterson Building Group
We call the Drawable team ‘the Postmen’ … they always deliver!
project manager (property)
Australian Broadcasting Corporation
Dave and his team provide excellent service, a high level of accuracy and fast turnaround times. I would highly recommend him for any AutoCAD or Revit services, from assisting with design to as built documentation.
Love the fantastic service that I have been given from all the team for many years. Never fail to deliver and consistently support us with a great product. Always happy to recommend Drawable!
senior facilities consultant
Australis Facilities Management
We utilise Drawable for all our drafting and engineering needs, Dave and the crew work seamlessly with our Design and Project Managers. Great service.
Somerville Electric have been using Drawable’s services for over 8 years and we have been astonished at their level of professionalism. We are very pleased with the quality and collaboration on all projects along with the timely responses.
Stowe CBD has found Drawable most reliable and mistake-free with all our CAD. Not only is their pricing very competitive but we have found their work to have a very quick turnaround, which helps the supply of documentation to our clients.
Sydney CBD manager
I have been using Drawable for shop drawings, revisions and as builts for eight years both in my current role and with my previous employer, ADCO Constructions, and they consistently provide great service. Their work is accurate and they always meet our tight schedules. A joy to work with.
I’ve been using these guys for years. No matter how bad my mark ups are they always turn around a professional job in a short period of time. I would recommend this team to anyone.
Drawable has provided our business with as built drawings for numerous projects over the past 9 years. We’ve always had great results, even when the info we send is not as detailed as needed. Dave and his team just know their stuff.
Fast Track Communications
Great experience from Dave and the team at Drawable. Highly recommend their services for any contractor needing AutoCAD and Revit drafting solutions.
Very responsive and the quality and project delivery was second to none.
Excellent team and quality drafting. From the smallest of changes to a complete Revit design, these guys are the best in the business.
We’ve been working with Dave and the team for the past 12 months – they’ve been extremely professional and a pleasure to deal with. Drawable always have a quick turnaround on all drawings. I will be using them in the future and would highly recommend them to others in the industry.
We utilise the services of Drawable for our as built drawings. We always get a professional and reliable service, good communication and great staff to work with!
4 Fold Building Services
We’ve been working with Dave and the team at Drawable for over 12 months and cannot recommend them highly enough. BIM and 3D modelling has been great with Cameron. Always turning drawings and models around early or on time.
Our company has been using Drawable for quite some time and we have always been pleased with the efficiency and the quality of the work they produce. We would highly recommend using Drawable.
I have had the pleasure of working with Dave and his team for around nine years now and nothing is too hard for these guys. My requests can be anything from an adjustment to an existing drawing to complete new drawings and the work is always produced as asked.
Dave’s deep and detailed knowledge of the industry makes working with Drawable a breeze. His consistency and reliability is second to none.