Just think about it…it’s arguable that building services professionals could gain just as much as architects from working with the latest 3D modelling tools.After all,when you are creating a piping system,for example,it needs to work and fit with other services in all dimensions – not just on a flat drawing.

Until recently,there have been good reasons for CAD managers and engineers to put off taking the plunge from traditional 2D drafting to 3D design software - one being the lack of products on the market which allow a gradual,planned migration from 2D.After all,who needs the upheaval and potential downtime of a ‘no going back’ software implementation – particularly during a busy period?And then there is all that data created.

It’s true that the construction industry has become more collaborative,but you may be wondering how all the information generated fits together.And whose fault is it if the original data is wrong? Doesn’t the building services engineer have to work around any errors and make sure everything fits together?

In these blame-crazy times,it’s not surprising that few want to stick their neck on the line and champion a change.

So what currently happens?Take,to begin with,the preliminary processes of design.The engineer has an idea and then tests it to see if it works,creating a conceptual design.Working in 2D,this stage can be pretty tedious and approximate,developing systems from first sketches,defining general size and area requirements and identifying what will be needed through time-consuming analysis.

Unfortunately,things don’t get much better at the design development stage.Here,there are lots of low-value drafting tasks and manual checking of work.Revisions are constantly being made to fine-tune the design,and of course,these all cost time and money.

In fact,conventional ways of working don’t make it easy to change the design just to get it right.This can really stop engineers thinking outside the box and trying out more creative solutions.

Working with others can be problematic too,particularly on a larger project where there are numerous teams installing different services.It’s not uncommon for the designs to clash,leading to expensive changes late on in the process.

And even if clashes are avoided,there can be access issues such as doors that won’t fully open or trip hazards.Consequently,there’s much adjusting to do on-site in order to make sure everything works together.

Working in 2D also makes it difficult to communicate a design to team members of different disciplines or to clients – for example, when issuing tender documents.Before migrating to 3D design,the Essex-based consultant mechanical and electrical building services practice,John Noad (Building Environment)Limited found it took them:“Several hours to create additional views and for plant rooms we had to generate complete drawing sets and numerous sections.

This meant that if there were changes to the building layout that dictated relocation of plant and services,there would be a whole series of drawings to change and co-ordinate.”

It could, at times,be extremely difficult to get the design out to tender within the deadline.

Until recently,if engineers wanted to design in 3D they had to work to achieve this with AutoCAD or Autodesk Architectural Desktop, building up their own parts library as they went along.

This had the potential to hold up the whole proceedings – not an ideal situation when timescales are tight.

However,by overcoming the industry’s natural suspicion of all things new,building services engineers can put themselves in a win-win situation.The key to this is the latest building services software that enables users to work in both 2D and 3D depending on the task in hand.This not only allows them to choose the most appropriate method for the job,it also enables the use of legacy documents and, importantly,a planned and gradual implementation.

Designing in 3D entails making a stepchange from working with traditional lines,arcs and circles to working with 3D geometry – not as difficult as it sounds as it means using ‘objects’ such as equipment,ducts and pipes that are representations of the real thing.

These have been programmed to interact with other objects making them

‘smart’ or ‘intelligent’.For example,a duct knows how to adapt to different components –if sizes don’t match;it automatically adjusts with appropriate transitions.As a result,this way of working is very intuitive and simple as the design itself tells you if something is wrong.

The objects then piece together to make a full screen model of a design. Using the latest model-based design technology,whenever a revision is made at any time throughout the design process,related views and schedules,for example,are automatically updated,co- ordinating the entire model.

There’s no need for pages of calculations and hours of checking to make sure they have been carried through across the design.

Extensive libraries of UK industry specific parts and equipment are integrated into engineering specific tools to make the documentation process even more efficient.Built-in design calculators and links to leading industry analysis applications take away the need for manual data transfer,while helping ensure that the work done in design development is available for immediate use during the documentation process.

Also,the plethora of data isn’t a problem – rather it’s at the heart of the real benefits of working this way and should be seen as a constantly updated asset to be used throughout the whole design/build process.The single database can be used by all project members from architects through the engineering phase,for builders and then ultimately for owners.

This means everybody is working to the same current specifications, minimising the costly errors further down the line at the construction stage – and ultimately the risk of litigation as a result.For example,relevant data such as design geometry,part specifications and scheduling information is always available and easily accessible,so if you need to make decisions during the process, you have all the data you need there.

And any fears that this just means perpetuating errors all the way down the line can be easily allayed.As the software does just what automated systems should do –that is take away the tedium of constant checking and other routine calculations - worries about accuracy can be put to one side, leaving the user free to create the best design possible.

John Noad decided to convert to 3D design when the company was invited to design the domestic services for a 600-property estate of timber-framed houses at RAF Lakenheath in East Anglia:

“When building on this scale,there can be significant differences in the way the numerous trade teams install the services,especially with so many identical properties.We had to agree common routes for services so that that there would be no clashes otherwise there could be major rectification costs,” said Stuart East .

“We also wanted to save time on site by providing routes for the services during manufacture rather than on-site during house assembly.Designing in 3D was the only realistic way of ensuring that everything was in the right place before site work started.”

Floyd Davis,CAD Manager at John Noad takes up the story:“The main thrust of our work was pipe services and Autodesk Building Systems (ABS)was the solution that most met our requirements.I had been drawing in 3D in AutoCAD.ABS speeded things up tremendously.”

The first large-scale proof of the value of the software to John Noad was provided with a 90,000 square foot office refurbishment in London’s West End.This five storey 1950s structure was not designed to take the weight of a plant room at roof level and the team devised a solution locating it at basement level rather than taking up rentable floor space.

“It was probably the most complicated set of services distribution we’ve ever done since we started the business nearly 20 years ago,” said East.“This approach would be extremely difficult in 2D.”

Using ABS also addresses the challenge of tendering documents.Now the company uses ABS to design the plant and services and NavisWorks to walk clients through the 3D model.“We really do save a lot of time at the tender stage.We tend not to issue elevations in drawing packages any more.Instead,we’ll send out one plan coupled with an appropriate number of 3D views.

The time it takes to generate these is minimal.” So anyone in the industry who is reluctant to switch to an objectbased CAD technology should ask themselves about their objectives. Is it merely to make a drawing? Or to produce a design that can be effectively communicated for construction?

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