Face to Face in a Fair Game

Pretty 24 is a new cream on the block. Its advertisement takes a potshot at various narratives associated with fairness advertising in India; however, its communication is silent on the benefits of the product. The angry (or upset) young women vent their ire as they feel betrayed by the hordes of Fairness creams in the market. The advertisement ends with a product shot, claiming it as a cream for every skin tone. The brand targets women between 20 and 35 years of age, as reported in livemint.Pretty good… The fairness cream market in India is fairly mature. From general purpose Fairness creams to Men’s Fairness creams to dark spots reduction fairness creams to winter fairness creams; every conceivable sub-category promise has been exploited to grow the market, which is reportedly around INR 4500 crore, and growing! In such a scenario, category creation by careful segmentation holds the key to success for a new entrant in a crowded shelf as the `Anti’ position puts the new entrant in direct competition vis-à-vis the rest. Also, the ability to leverage existing distribution network adds to the muscle mass so critical for success. On all these counts, Pretty 24 sits pretty.


The dark side… Is Pretty 24 a little late? Is it being built on a carefully chosen plank or hunch? Or, is it a manifestation of confusion at the Marketer’s end? Is it an idea whose time peaked some 10, 15, 20 years ago?In India, the pride factor in one’s `own’ complexion has already gained ground; especially with girls-next-door winning the titles such as Ms India, Supermodel, etc. And to the buyer of very premium international brands, complexion has never been an issue. Over the years, most of the fairness cream brands have formulations that offer benefits beyond mild-bleaching to include skin moisturization at the very least.For the Fair’y Tales inspired buyers in Tier II and III, semi-urban centres; it is still `Fairness’ all the way to success. So who is the brand Pretty 24 targeting? And what’s the `reason to buy’, it is offering to the consumers (unless subsequent campaign reveals it).The leader in the `Fairness’ category i.e. Fair & Lovely has long gone beyond `Fairness’ to `Confidence’ and `Success’. There is more to the Brand Fair & Lovely as evident in the tales chronicled in the Fair & Lovely Foundation brochure done by this author. The foundation is doing yeoman service to nurture aspiring, young talented women.


It remains to be seen how the new entrant will affect it. Is Pretty 24 an attempt to cut an instant slice of fairness cream market in India? At mere 1% share translates into INR 40-50 crore!In all fairness… Pretty 24 has to its credit of being not just another offering. It takes immense guts to experiment, to be different. The communication and the proposition make one take cognizance of the brand. But will it make a dent? For a brand’s salience eventually is connect with (benefit offered to) the consumers; and not mere attempts at evoking resentment against other brands.

Has BIM Changed MEP Design Workflow?

The MEP design and installation workflow involves a number of stakeholders and parties that are collectively responsible for overseeing a series of stages that will result in the building engineering (or building services) to be planned, designed, spatially coordinated, fabricated, installed, commissioned and maintained. Typically, the building services design stage follows the initial architectural design, from which point it can usually be designed in parallel with further architectural as well as structural design changes.

The engineering teams that typically design building services solutions are usually in one of two groups. The first group is typically the building designer, also known as the consultant engineer or the design engineer. It is the role of the design engineer to work closely with the architect to develop the overall building engineering elements including lighting, cooling, heating, drainage, waste, fire prevention and protection services. Traditionally, the design engineer will not be involved in the detailed spatial design of these services. Instead the detailed spatial design and installation would normally be handled by the second party, known as the MEP contractor (M&E contractor) or trade contractor. The MEP or trade contractor is responsible for evolving the initial consultant design into a workable and installation-ready building services solution.

In some instances, there is also a third party involved – the fabricator, who will be responsible for creating MEP components such as ductwork or pipework elements or in some cases pre-fabricated solutions that consist of pipework, electrical ladder, plumbing, ductwork and sprinkler within a frame (module) that is delivered to site for installation in risers, plant rooms and corridors.

This article is concerned with the role of the MEP designer and MEP contractor, specifically, the focus for this article is to discuss how BIM (Building Information Modelling) has influenced the MEP design workflow between the designer and the contractor.

Current MEP BIM Workflow Options

Essentially there are five different MEP design workflow scenarios that currently exist and these will be discussed in the article. They are as follows

  1. Traditional 2D design and 3D BIM coordination
  2. 3D MEP design and 3D BIM coordination
  3. Designers 3D BIM design and coordination
  4. Contractor 3D BIM design and coordination
  5. General contractor 3D model coordination

Traditional 2D Design and 3D BIM Coordination

Considering the traditional MEP approach first, this is where a consultant will create 2D design outputs, which include 2D plan layouts, 2D sections and MEP (M&E) schematics. This will indicate the design intent for the building based on the use specified by the architect. Once the consultant has completed this design information he will pass on the information to an MEP contractor who will be responsible for creating the MEP coordinated solution. This article assumes that the contractor will create a spatially coordinated 3D BIM model using BIM tools such as Revit MEP and Navisworks. The contractor will use the design information and create an installation-ready solution which takes into account installation, efficiency of pipe runs or duct bends, space for lagging and hanging the services, access for post install maintenance and so on. This traditional MEP approach, from a 2D design to a 3D model has existed for the past couple of decades and allows the contractor to add additional information into the model that can be used by him and by facilities management companies after the installation. The use of the 3D tool such as Revit is of course useful as it is an intelligent model, with parametric components and therefore, as well as allowing the contractor to identify and resolve clashes before any time is spent on site, it has other uses and applications where model ‘information’ is used and relied upon.

3D MEP Design and 3D BIM Coordination

The second workflow method is more directly influenced by BIM. As the MEP designer, one will use BIM tools to create a 3D model and associated drawings during his initial design phase (rather than a 2D design) before this information is handed across to an MEP trade contractor. The MEP design engineer will typically create a 3D model due to customer specifications and requirements for a BIM model, as in many cases a federated model (which combines the other disciplines in a single model) is needed by the client for a weekly review and hence the MEP consultant cannot simply provide a set of 2D drawings. In this workflow, the BIM model is effectively a 3D representation of what would otherwise be a 2D deliverable. It will therefore consist of areas where further changes are still needed by a trade contractor. Such examples include the use of library items rather than specific MEP trade contractor procured elements that may be used in the model. The creation of a 3D BIM model at this stage by the consultant is also subject to multiple architectural and structural model changes. These have a knock-on effect on the MEP solution as it is effectively a work-in-progress model for MEP with constant architectural and structural changes and therefore will never have the same level of efficiency, in terms of layout of services, compared to an MEP model where the architectural and structural models are frozen. The downside of this workflow method is of course the extra time taken to create a BIM model by the consultant team. Added to this issue is the fact that 3D modelling expertise and skills within a consulting engineering team can sometimes be limited. Once the consultant completes his model and passes it to the MEP contractor, the decision as to whether the contractor should adapt the model or start the modelling process from the start is really based on the quality of the model to start with. In reality both scenarios will exist, in some cases the MEP trade contractor is better off starting the BIM model again using only the 2D design drawings that are created by the consultant from his BIM model, while in some rare cases the trade contractor will use the consultants MEP BIM model and adapt and modify it with his changes, to make the model ready for installation. In both scenarios, the MEP contractor will always look to make value engineering additions and changes to the model as well as procurement led model changes.

Designers 3D BIM MEP Design and Coordination

The third MEP design workflow method is a more pure and direct consequence of BIM and it actually also starts to promote the benefit of BIM more significantly as it gets closer to ‘virtual design and construction’ aims of the industry. In this workflow the approach of design engineer is to create a BIM model that is spatially coordinated and that is using the actual specified components for the project. Typically, the consultant during this phase will have a longer period of time to create the model, allowing him to absorb the changes from structural and architectural disciplines as they progress through the detailing stages. The fact that the model is then coordinated with the structure and architecture as well as other MEP services allows the consultant to create a model that is being created according to an installation standard that is now more usable by an installer or fabricator. When the model in this workflow method is passed on to a contractor, the contractor may still wish to make final changes and adjustments in a round of value engineering. Typically, the contractor will use the same model in this workflow and make changes to the model provided by the MEP design consultant. Additionally, it is probable that the consultant engineer will not have provided invert (height) levels or dimensions from gridlines and walls for the MEP services on his drawings. In such cases the contractor will therefore have to create more detail in the drawings, but again contractor could use the consultant’s drawings and progress them in more detail for his/her use.

Contractor 3D Design and Coordination

The fourth workflow method involves MEP contractors (or trade contractors) taking on the design responsibility as well as the coordination responsibility. Whilst the coordination responsibility is an established skillset with experience of developing detailed and comprehensive vertical and horizontal strategies for coordination being part of the contractor’s core skills, the design responsibility is a new element for the contractor. This was traditionally known as a design and build approach; however, it is now becoming increasingly common especially in cases where companies are seeking to have rapid design and detailed coordination completed. Typically, the components to be used will be specified by the end client, allowing the contractor to design and model before creating his detailed coordinated drawings from the model, to allow installation and fabrication if needed. The reason that this particular workflow method is not the most popular at present is simply due to the volume of work in the market and also the design responsibility that also has to be assumed as in most cases, contractors may not wish to accept this risk or indeed they may not have the resources to complete the design work. For this workflow method to exist at all means that the contractor has to employ design staff directly and provide design liability insurance to allow him to design the MEP solution as well as install it. The benefit of this workflow option is obviously the time efficiency that is realized and therefore the cost benefit, as the cost of utilising contractor resource will usually be lower compared to expensive design engineering firms. However, it does come with some risk as the design expertise that design engineers possess cannot be easily replicated by contractors, even if they do employ in-house teams.

General Contractor 3D Model Coordination

The fifth variant of MEP design workflow is based on creating coordinated MEP models similar to the traditional 2D to 3D approach but for a different customer group. In this workflow method a 2D architectural, structural and MEP design that is to be used by a main contractor (or general contractor) is then progressed into a 3D BIM model by the contractor to assess the validity and completeness of the model. In some cases, some of the design elements from the different disciplines may be presented in 3D while others may be in 2D. It is also possible that different disciplines may provide models in different software that may or may not present software interoperability challenges. In such instances, a team will typically be employed to use the design data from architectural, structural and MEP designers to then create a 3D BIM model based on actual data. The aim is to identify any inconsistencies in the design data by identifying any clashes in the model, allowing the contractor in such a workflow method to effectively mitigate his/her potential risk. Any problems found within the model are usually passed back to the designers to make amendments to their 2D design for subsequent changes to the 3D BIM model which is ultimately owned by the main contractor. This BIM workflow solution is becoming less common now because MEP contractors and designers are creating BIM models themselves.

In summary, BIM has introduced a number of new workflow variants to the MEP design services sector. The previously tried and trusted method of a 2D design, from a designer, that was developed into a 3D coordinated MEP model by contractor is no longer the workflow solution used as firms now have many other variants and alternatives available. Along with BIM Modeling, other developments in the construction sector, including collaborative online working and work sharing have also contributed to the uptake levels for BIM and impacted the changes to workflow.

In terms of the MEP design workflow options, the most popular of these as we move forward will be the third option, which is the consultant creating a BIM model that is spatially coordinated, or the fourth option which is the contractor taking on the design responsibility as well as creating the coordinated BIM model. Both options are effectively a change to the traditional approach for MEP design and both point to a single source for the model and drawings as opposed to the historical two-tier design approach. All options discussed will require competent BIM coordination and MEP modelling teams and resources. XS CAD, with its large MEP coordination team and MEP engineering design team, which consists of mechanical and electrical engineering professionals, is well placed to deal with such projects for companies based in the USA, UK, Canada, Australia and New Zealand. As all are regions where BIM is now the preferred solution, XS CAD, with more than 16 years’ experience and a presence in each market is an ideal option for such companies.

Decoding the Ductwork Design Process, Methods and Standards

Today, one of the significant objectives in MEP engineering design for HVAC design engineers is to improve energy efficiency, maintain air quality and thermal comfort. Energy efficiency, air quality and comfort in a building depend on how heating, cooling and air distribution systems are designed and this is where careful ductwork design plays a significant role. Ductwork and HVAC system design are important as it ensures indoor air quality, thermal comfort and ventilation. If the HVAC system and ducts are not designed accurately, it could lead to poor air quality, heat loss and make the conditioned space in the building uncomfortable.

The primary function of the ductwork design system is to ensure a least obtrusive channel is provided through which cool and warm air can travel. When designed accurately, HVAC air distribution systems will play an important role in countering heat energy losses, maintaining indoor air quality (IAQ) and providing thermal comfort.

To understand how ductwork can be designed in a cost-effective and efficient manner, this article decodes ductwork design and provides a brief outline of the design process, methods and standards.

What is Ductwork?

The basic principle of ductwork design is to heat, cool or ventilate a building in the most efficient and cost-effective way. The primary function of ductwork is to design conduits or passages that allow air flow to provide heating, cooling, ventilation and air conditioning (HVAC).

In the duct design process, the basics of air flow must be understood. Return air goes into an air handler unit (AHU), through a filter and into the blower and with pressure it goes through the A coil or heat exchanger and then it goes out into the supply air system. If the ductwork is designed correctly it enables the AHU to produce the right amount of air through the heat exchanger. In a typical air distribution system, ducts must accommodate supply, return and exhaust air flow. Supply ducts provide air required for air conditioning and ventilation, return ducts provide regulated air to maintain IAQ and temperature and exhaust air flow systems provide ventilation.

For ductwork design to be efficient, MEP engineering design teams need to have designers with a mechanical and engineering background. Ductwork design specialists or building service engineers must also possess thorough knowledge of other disciplines such as architectural, civil and structural concepts to ensure HVAC systems are clash free.

The Ductwork Design Process

The ducting system design process is simple, provided that the specifications are clearly mentioned and the inputs regarding application, activity, building orientation and building material are provided. Based on the information provided calculations can be completed to create an energy-efficient and clash-free design. Typically, air conditioning and distribution systems are designed to fulfil three main requirements such as:

• It should deliver air flow at specific rates and velocity to stipulated locations.

• It should be energy efficient and cost effective.

• It should provide comfort and not generate disturbance or objectionable noise.

The process of ductwork design starts once architectural layouts and interior design plans are provided by the client or MEP consultants. Building service engineers then require specification requirements such as application, the number of people, the orientation of the building and architectural characteristics to make calculations on heat load and air flow. Before any calculations are carried out, single line drawings are drafted to showcase the flow of ductwork in the building. Once they are approved, calculations for heat load and air flow are conducted. Once the heat load calculations are complete, the air flow rates that are required are known and the air outlets are fixed. With the calculations, specifications and layout, the ducting system design layout is then designed taking into consideration architectural and structural details of the conditioned space and clashes with other building services such as electrical, plumbing (hydraulic) and mechanical services.

To start the ductwork design process there are inputs required regarding details about the type of application, specification requirements, building orientation, architectural characteristic and material.

• Application type - Ductwork design will vary based on the type of application the building will be used for such as manufacturing, data centres, medical applications, scientific research and comfort applications such as restaurants, offices, residences, institutional building such as schools and universities.

• Specification requirement – To create an efficient duct design, designers need to know what type of activity will be conducted and the average number of people that will use the conditioned space. This will help in calculating the air flow, velocity and heat load required to maintain temperatures and IAQ. In comfort applications, for instance, an office or restaurant will require different duct design and air velocity than a residence.

• Orientation and material of the building - The orientation of building and material used plays a key role in gauging heat absorption which will help determine the cooling and ventilation requirements. Based on whether a building faces north, south, east or west, and where it is geographically located, heat absorption can be calculated. The type of material used for construction also affects the amount of heat gain and loss of the building.

The challenges of incomplete inputs or non-availability of required inputs are discussed in an upcoming article on Ductwork Design Challenges and Recommendations.

Ductwork Design Methods

Ductwork design methods are usually determined based on the cost, requirements, specifications and energy efficiency standards. Based on the load of the duct from air pressure, duct systems can typically be classified into high velocity, medium velocity and low velocity systems. There are three commonly used methods for duct design:

1. Constant Velocity Method – This method, designed to maintain minimum velocity, is one of the simplest ways to design duct systems for supply and return air ducts. However, it requires experience to use this method as the incorrect selection of velocities, duct sizes and choice of fixtures could increase the cost. Moreover, to maintain the same rate of pressure drop in duct runs, this method requires partial closure of dampers in duct runs (except index run) which could affect efficiency.

2. Equal Friction Method – This conventional method used for both supply and return ducts maintains the same frictional pressure drop across main and branch ducts. This method ensures dissipation of pressure drops as friction in duct runs rather than in balancing dampers. However, like the velocity method, partial closure of dampers is required and this could lead to noise generation.

3. Static Regain Method – This method commonly used for large supply systems with long ducts is a high velocity system that maintains constant static pressure before each branch or terminal. While this is a balanced system as it does not involve dampering, longer ducts may affect air distribution to conditioned spaces.

While different duct design methods used vary from application to application, duct system performance and system balancing and optimisation need to be considered. After the air handling unit (AHU) is installed, the system needs to be balanced and optimised to enhance performance. In system balancing and optimisation, air flow rates of supply air outlets and return air inlets are measured, and dampers and fan speed are adjusted. Especially in large buildings, balancing air conditioning systems may be expensive and time-consuming, but it is required as it provides benefits that outweigh the cost incurred in installing the system. To minimise total and operating cost, many optimisation methods are used as such as the T-Method Optimisation described in the DA3 Application Manual of AIRAH (Australian Institute of Refrigeration Air Conditioning).

To design air distribution systems that are energy efficient and cost effective, HVAC system designs must include basic engineering guidelines and adhere to certain design standards. Let us consider some of the guidelines and standards used in the industry in different countries.

Ductwork Design Standards

When designing air conditioning systems, HVAC design engineers must be knowledgeable about the basic methods, guidelines and standards applicable, from the type of units used, calculations required, methods of construction, type of material, duct system layouts, pressure losses, duct leakage, noise considerations to optimisation using testing, adjusting and balancing (TAB). Listed below are some of the standards organisations and associations in the U.S., U.K., Australia and India, that provide manuals, codes and standards for the HVAC industry.

U.S.

• SMACNA (Sheet Metal and Air Conditioning Contractors’ National Association) – It provides a manual on HVAC systems duct design that includes basic yet fundamental methods and procedures with importance on energy efficiency and conservation. While the manual does not include load calculations and air ventilation quantities, it is typically used in conjunction with the ASHRAE Fundamentals Handbook.

• ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) – It is an association that emphasises on the sustainability of building systems by focusing on energy efficiency and indoor air quality. The ASHRAE Handbook is a four-volume guide that provides the fundamentals of refrigeration, applications, systems and equipment. Updated every four years, the handbook includes international units of measurement such as SI (systems international) and I-P (inch-pound).

U.K.

• CIBSE (The Chartered Institution of Building Services Engineers) – is the authority in the UK that sets standards for building services engineering systems. The Codes and Guidelines published by CIBSE are recognised internationally and considered as the criteria for best practices in the areas of sustainability, construction and engineering.

• BSRIA (Building Services Research and Information Association) – is an association that provides services that help companies enhance their designs to increase energy efficiency in adherence to Building Regulations, mock-up testing of systems and BIM support.

Australia

• AIRAH (Australian Institute of Refrigeration Air Conditioning) – provides technical manuals for professionals in the HVAC industry and information ranging from air conditioning load estimation, ductwork for air conditioning, pipe sizing, centrifugal pumps, noise control, fans, air filters, cooling towers, water treatment, maintenance, indoor air quality and building commission.

India

• BIS (Bureau of Indian Standards) – is a national authority that provides standards and guidelines as per the International Organization for standardisation (ISO). The handbooks by BIS stipulates the code of practices applicable to the HVAC industry such as safety code for air conditioning, specification for air ducts, thermostats for use in air conditioners, metal duct work, air-cooled heat exchangers and data for outside design conditions for air conditioning for Indian cities

• ISHRAE (The Indian Society of Heating, Refrigerating and Air Conditioning Engineers) – provides indoor environmental quality standards and testing and rating guidelines based on common IEQ parameters standards and criteria for the classification of buildings based on energy efficiency.

While HVAC design engineers must keep relevant standards in mind and ensure that local codes are applied in designs, energy efficiency is a primary objective as well. Ductwork design plays a significant role in regulating indoor air quality, thermal comfort and ventilation. The key function of ductwork design is to provide the least obtrusive channel through which cool and warm air can travel in the most efficient and cost-effective way.

Inaccurate duct designs could result in poor indoor air quality, heat loss and uncomfortable conditioned space in the building. A well-designed air conditioning HVAC system will ultimately optimise costs. By regulating pressure loss, selecting the right duct size, balancing air pressure and controlling acoustics, ductwork designers could optimise manufacturing, operational, environmental and commissioning costs.