Nov 9, 2016 -- Building construction as a process has transformed itself from blue prints, conceptual sketches and drafts to rendered models, virtual design constructions and as-built models. It isn’t a drawing & drafting business anymore; instead it has become a business of who has a better show of what will be built.
Building Information Modeling - BIM is the one that is stealing the show for this transformation. The capability of BIM to generate information rich intelligent 3D models has essentially transformed, from the way which general contractors, architects, engineers and construction firms used to work on their past building construction projects. The AEC professionals are of the opinion that the kind of jobs, which markets need them to accomplish are nearly impossible and most contractors would run away from it, had BIM not been available.
Interestingly, several surveys regarding BIM usage, awareness, its applications, its effect on projects and other statistics reveal several interesting facts and benefits about BIM. Let us start uncovering them one after another.
BIM generates models not a set of lines
Initially when computer aided drafting replaced drawing sheets and boards, what it could do was make the drawings more accurate with a precision of up to four decimals; only that. However, on the other hand, with BIM, the models could be generated in 3D, and extended to 7D, with many other details, and rendering effects. The contractors would know what will be built. The need to interpret the lines was eliminated.
Dr. Chuck Eastman, professor at Georgia Institute of Technology, said to The Economist that, “There's no structure that tells you that this line is a wall, stair or window.” With this level, it was difficult from higher authorities to interpret each line and consumed a lot of time. This is totally eradicated by BIM, which in fact presents the project managers and architectural firms with the as built models for virtual visualization even before the construction starts.
Get a virtual walkthrough even before the physical construction starts
In a survey conducted in USA by Dodge Data and Analytics, 74% of the contractors, 64% of architects and 68% of project owners said that the use of BIM improved the final constructability of design. This data clearly suggests that function of BIM has helped in overcoming the challenges faced in generating designs and drawings, when clubbed with various disciplines.
The capability of V-Ray, Photoshop, and Revit Architecture to generate walkthrough videos, having all the details of the as-built structure, helps the project owners know what the built structure will look like and if necessary changes can be done as and when required.. This design alterations before finalization can reduce a lot of rework and save the time.
Allows building with strength
A good design is of no use unless blends finely with engineering aspects for appropriate strength, so that it can sustain the load it is designed to carry. To comply designs with engineering, software like Tekla can provide the information related to steel detailing, rebar detailing and precast and prefabricated detailing of the structure. The details generated through these documents helps in determining the cost and Bill of Materials: BOM for the estimation. It generates the files in various formats like DWG, DNG, DXF and PDFs. However, it emphasizes on IFC standards as it can deal with objects in any geometry and exporting becomes a convenience.
Clash detection and resolution
For large construction projects detection of clashes from the drawings prepared by different disciplines is cumbersome and consumes considerable time. For many surveys and inputs, every time, half of the respondents would agree to the fact that BIM helps in reducing the errors and making the MEP designs clash free.
The errors are mainly due to the clashes observed by the collaboration of design received from architects, structural and MEP engineers. The detection of these clashes and resolving them with alternate feasible design in Navisworks saves a lot of time and rework. If these MEP clashes are detected after the construction has begun, it will lead to a lot of wastage of man-material resources, but as the entirely animated design ensures it is clash free.
Planning, scheduling, costing and maintenance
One of the major applications of BIM is that it facilitates coordination and collaboration amongst the activities across all disciplines involved to erect a structure as a whole. Once the designs from each discipline is received, and checked for clashes, BIM experts generate the construction documents for proper streamlining of various interdisciplinary activities to be carried out seamlessly.
The as-built models with higher Level of Detailing – LOD helps in knowing the quantity of building product, like small electric switches, bath fittings, cable trays, furniture, and of course the building construction material with their quality and manufacturer to know the cost estimation for the project.
General contractors are empowered to place their bids based on this information and hence this has, now-a-days become a baseline tool for projects, small or large, simple or with multiple complexities. 70% of the owners responded to the Dodge Data and Analytics that they were able to plan the construction phase in a better manner with help of BIM.
In addition to this, BIM helps the O&M teams for the maintenance and regular up gradation of the building products as BIM lets you know the last replacement dates and which parts are to be replaced. One of the Surveys by International Association for Automation and Robotics in Construction ( IAARC) shows that a major section of people have already adopted or have a thought of adopting the maintenance consideration during the design phase. BIM is one tool to do both these works simultaneously.
Energy modeling and sustainable design
Every major facility is consuming a huge amount of electricity so the facility owners are now keen on obtaining the National Green Building Council Certification ( LEED in USA, BREEAM in Europe, ESTIDAMA in UAE and other across the world) to save electricity and hence get tax benefits. The design of MEP layout is made according to the orientation of the structure, occupancy of the facility and the climatic conditions in the area so as to cut the energy consumption used in HVAC systems, motors, pumps, water supply, lighting and elevators.
Finite Element Analysis is done for the as-built models to know the strength of the building and to perform the test to see what levels of wind loads, seismic vibrations, thermal and other sudden loads it can withstand and build a sustainable design.
Better end results with BIM
The productivity, efficiency and quality of work have surely been improved and project managers have been able to meet the deadline in spite of so many practical, unavoidable situation. The idle time of the workers has been reduced due to proper streamlining of activities and lesser man-material movement. The exact estimation of cost is predictable with the quality of material used to empower the facility owner take proper decisions.
Thus, with BIM having such countless benefits at every stage of construction project right from planning to the time actual construction starts, architects, structural engineers, MEP contractors, construction firms and individual stakeholders are sure to benefit with BIM.